Tiny machines

It's been a while since I posted, so I thought it was about time I wrote something. And what better to write about, than what I spend every day working on!

If you studied biology in school may remember this: DNA to RNA to Protein.

Proteins do almost everything in the cell. Anything you can think of, a protein does it.

Generate energy? Protein.

Shuttle things around? Protein.

Repair damage? Protein.

At any one time, a cell has tens of millions of proteins, all working to keep the cell healthy and functioning as it should. It's a mind-boggling operation, and it is happening in every one of your cells right now. When you consider that you have trillions of cells (there are more cells in your hand than there are people on earth!), the staggering complexity is difficult to grasp.

The cell needs to make all those proteins, and it needs instructions so it can make the right ones at the right time. These instructions are encoded in your DNA. Each "instructional" section of the DNA is called a gene, and every protein is encoded by a different gene. Every cell in your body has its own copy of the DNA (with some exceptions), and it is very precious. If the DNA gets damaged you lose the instructions for the proteins, and the cell will probably die as a result. Because of this it is stored in the nucleus, away from most of the things that could damage it. The problem is, proteins can not be made in the nucleus, so the cell needs a way to get the instructions for the proteins out of the nucleus, and into the body of the cell, the cytoplasm.

Life has come up with an ingenious solution to this problem: the cell can make a "photocopy" of the instructions of the protein it needs, and it can take that out of the nucleus. This "photocopy" is called mRNA, and it is then used to make as many copies of the protein that a cell needs. That way the DNA is kept safely locked away, but the cell can still make the protein. The process of "photocopying" the DNA to make mRNA is called "transcription".

I like to think of the DNA as an enormous book, that is kept behind lock and key in a special room in a library. There is only one copy of the book, so it is kept safe, away from all the people that work and visit the library. The problem is, people need the information that is in the book. In fact the book describes how everything works in the library, so without that information, the library would completely fall apart.

To get around this, a small number of trusted people can photocopy pages from the book, and they can then be passed to the workers in the library so they can carry out the instructions. If the photocopy gets damaged it isn't a problem; another photocopy can just be made.

In this analogy the photocopy is mRNA, and in reality, when it gets taken out into the cytoplasm, that is only the start of making a protein. The mRNA has to be transported to little machines called ribosomes, and the ribosome reads the mRNA, and produces the protein. This process is called "translation" because the cell is translating the instructions contained in the mRNA into a functional protein.

All of the tens of millions of protein in every cell are made like this, and the tiny machines (ribosomes) are at the centre of it all. They are amazing things; every single cell that has ever existed had ribosomes in it. Every animal, plant, fungus, and bacteria has ribosomes, all busily making protein from mRNA, sustaining all life in the process. And these ribosomes are what I spend my time studying.

Like everything in life, how they work is extremely simple and complex at the same time. The ribosome is shaped vaguely like a burger bun, with two parts, and it attaches mRNA with one part above and the other below. The mRNA then feeds through the ribosome until it has all been read. At the same time it is reading the mRNA, the ribosome is also making the protein (which is coming out the top of the ribosome in the gif above), so when it is finished reading, it is also finished making the protein.

For a long time it was thought that this process of reading an mRNA and producing a protein (translating the mRNA) was a pretty passive one. If the cell needed a lot of a protein, it would make lots of mRNA, and as a result, the ribosomes would make lots of protein. While that is true, we now know that it is not the only way a cell can make more protein, and that ribosomes have an important role in making sure that the correct amount of protein is being produced. If one ribosome is reading an mRNA, it will produce one protein. But if 10 ribosomes are reading the same mRNA, they they will produce 10 proteins. If a ribosome takes 20 seconds to read the mRNA, it will only produce half of the protein compared to one that takes 10 seconds. These (and many other subtleties) give ribosomes extraordinary control of the fate of the cell, and we are only beginning to understand this.

It's not an exaggeration to say that understanding ribosomes is key to understand all life. They carry out one of the most key processes in life, but there is still so much we do not understand about them. We also know that many diseases hijack ribosomes, including cancer, so increasing our knowledge is obviously important, and that is what we focus on in my lab. Tiny, beautiful, complex machines, that are so important that life wouldn't exist without them. And people wonder why I love my job so much!

Talking science with the public (part 2)

Part 1 of this blog described a few simple things that you can do to make your talk more engaging for the general public, mainly just keeping it simple. That is really all you need, but if you would like to think about it a little more, there are also some techniques you can use to improve it even further.PoSMost public science presentations will involve various strange or fascinating things that you explain to the audience, and that is often enough for a very good talk. Present those facts with enthusiasm and humour, and follow the hints from Part 1, and you can have the audience rapt. With a bit of practice, you can give a very good presentation like this.However, it is also possible to incorporate more of a storytelling approach in to your presentation. No matter how interesting the topic is, if you just give the facts, you risk hitting the limit of your audience’s concentration. If you tell a story, you can keep people’s attention far longer. We are storytelling animals, and if the facts are presented as part of a story, we are far more likely to take them in. So if you are interested in incorporating facets of storytelling into your presentation, here are a few pointers that will help you do that.Before I start I should say that storytelling has many different forms, and what I describe here are simply suggestions. People intuitively know what a good story is, so if something feels right for your presentation, go with it. Aim for something empathic, exciting, and relevant; try to build a bond; most importantly have fun!

The Story Arc

Having a story arc is the most basic of tool in the storyteller’s arsenal, and it very often follows the same pattern. For example:The introductionThis allows people get invested in the story, makes them feel part of it. It can be an introduction to a topic or disease, or an introduction to you, and why you are passionate about your research. Try to include something personal here, something people can relate to and will make them invested in the story.The set upThe set up builds the story towards the climax or the point you want to make. A lot of people describe the state of the field or some of the challenges they faced in the work.The climaxThis is the turning point of your story, usually the breakthrough in the research, or the most important result that you want to talk about. It is the whole point of the talk, and everything that comes after this is about putting this finding into context.The slow downFollowing the climax, you can explain your finding in more detail, perhaps some more evidence for what you have foundThe endIt is effective to finish by describing the new normal. You can describe how your work has changed things, or the implications of your work. Does this suggest a change to treatment of a disease? Or how we think about something? What does this suggest for the future?This may translate to something like this:What I am working on is very important because [blank]. We used to believe that [blank]. This meant that [blank]. While we were studying it we realised that [blank]. This meant that [blank]. This is important because [bank].Or:Start with the purpose; why do you feel compelled to tell this story? Go on to describe the belief that you or society had, followed by how your work has challenged this belief. You can then go on to put this in contect, and describe what greater purpose it serves. Finally you can talk about what the work teaches us.Freytags_pyramidVery often the story arc is a simple progression forward in time. This is effective because there is a logical flow for people to follow, with each movement forward posing questions that will intuitively be answered in the next section.This chronological structure traditionally describes character-based progress, but it could just as easily describe the journey of your field, or your own research. It could be the case that you are the main character, and the story follows your journey through your studies.

The Anecdote

It is important that this forward progression in time is interspersed with reflection, adding detail, context, and emotion to keep people invested in the story. This is called “the anecdote” by Ira Glass, and this video describing it is well worth a watch.Such reflection is vital to storytelling. Try to make the audience feel what you felt. If something was confusing, tell them, and maybe explain why. It is very compelling when our perceptions of reality are challenged or changed in some way. Stories that are not intuitive hold people’s interest! If something was frustrating, describe it. These are the reflections that keep people interested. Using emotion like this helps build a bond with the audience which will always help keep them engaged.This mix of forward progression using the story arc, interspersed with reflections to connect with your audience, is the most well described and reliable structure your story can take.Of course, it is worth emphasising that there are a vast and rich set of techniques used by storytellers. The best talks mix various aspects of storytelling, and there are lots of resources online to help you if you would like to know more. Storytelling is part of our history, and even when simply presenting facts, we automatically frame them to make them more compelling. Use this blog post as an aid, but feel free to ignore it and go with what you think is best. We intuitively know a well told story when we hear one, so follow your gut. And to echo what I said in Part 1, enthusiasm is infectious, so enjoy yourself, and the audience will most likely do the same!There are some good storytelling resources available online. It is a well-studied topic, and lots of people have written great articles about it. YouTube is full of informative videos, and google throws up many great examples. Below are just a sample of them:How to Tell Your Story without Boring Your Audience to TearsThe Science of StorytellingCommunicating your research effectivelyRadiolab (a podcast about science and society, and undoubtedly one of the best storytelling podcasts out there)


This was written as advice for speakers at the Dutch Pint of Science festival. The 2019 edition of this international event takes place in from May 20 - 22, across 8 cities in the Netherlands. The festival hosts events in 24 countries. More details about your local festival can be found here.

Talking science with the public (part 1)

I have had the pleasure of helping organize the Pint of Science NL festival over the last 2 years. The festival takes place from May 20th to 22nd this year, and we will have at least 85 scientists talking about their work across 8 cities in the Netherlands. All the information can be found via this link.PoSAs part of a speaker's package we put together for the festival, I wrote a few things about how people can make their presentations more engaging for the public. Explaining complex science is sometimes a difficult thing to do, so below are a few suggestions to help scientists make their public talks as good as their scientific ones!Know your audience!A talk for college educated professionals will be very different to one for school kids. Try to aim your talk appropriately. Most of the time these kinds of talks will be for people who are pro-science, so luckily there is rarely a need to persuade people that evolution is real or that the earth is round. However, don't be surprised to be asked when we might finally meet aliens, or to explain telepathy.This is not a conference talk!There are a few simple things you can do to make your presentation better and more engaging for your audience. Remember, unlike at a scientific conference, people are not there to see all your data. The concepts and ideas that underlie what you do are fascinating, and describing them should make up most of your talk. Once you have introduced these concepts to people, you can personalise it a bit more, but it is still worth avoiding presenting a lot of data. Keep it relatively simple and easy to follow.Pointers for making a good talk:Everyone designs their talks differently, but here is a simple example structure that people find easy to follow:

Big picture; why people should care?

Main points (3 at most), kept simple and interesting

How your work is helping build a better future

 Big picture; why people should care?Start by showing the audience why they should care about your topic. Show them the "big picture", so they can put your work in the context of their own lives. This helps people relate to the work.Three main pointsWhat do you want the audience to remember from your talk? People have short memories, so stick to 3 main points at most. Focusing on a small number of main points helps you keep the talk easy. Remember, the people attending have little or no exposure to the concepts you are describing, so think about that when you are writing your talk. (If the talk is shorter than 15 minutes, you might want to limit it to 2 main points.)Get to the pointScientists are used to the “Background → Results → Conclusions” structure of a seminar. That should be flipped for a public talk, with the important conclusion coming early, and then expanded.How your work is helping solve the problem?Finish off by emphasising how your work will change things. You want the audience to have a basic understanding of the problem and your solution, but also to have some of the enthusiasm for science that led you to dedicate your life to it! Paint them an optimistic future, and show them how your work is helping us move towards it. This is a balancing act however, as we really want to avoid is over-selling the work. We all hate the “Scientists cure cancer!” headlines that we see in the newspaper, so try to make sure you provide enough realism into your talk!Other practical tips:

  1.     You should aim for one slide every 2-3 minutes of presentation at most. This is one of the big differences between a public talk and a scientific one. Talk to the audience; if you have too many slides you will end up talking to the screen.
  2.     Use plain language, and try to avoid jargon. Again, remember that the audience don’t know anything about your field. Avoid technical terms or acronyms as much as possible unless you have enough time to properly explain them.
  3.      Use visuals. A good image, video, or even live experiment can make it far easier for an audience to follow a complex topic. Be careful with figures from scientific publications, these are often too complex for a general audience. Making your own "cartoon" illustration helps to simplify and keep visuals consistent throughout your presentation.
  4.     Metaphors are also a very useful tool for explaining complex ideas. Just try to be consistent and don’t fall into the trap of mixing metaphors!
  5.     Convey your enthusiasm. You work on a fascinating topic! The aim of the game is to show the audience how interesting STEM is!
  6.      Take your time. As an expert it is easy to get carried away and fly through an basic talk like this. Take it slowly, and remember that people won’t be able to keep up if you are going too quickly.
  7.     Speak up, even if you are using a microphone. This sounds obvious, but during a talk there may be a lot of ambient noise, so make sure those people in the back can hear you.
  8.     Have fun! Everybody has different ideas when it comes to speaking to the public, so what I have detailed here are just tips to help you out. As you practice you will come to know what works for you and what doesn't. Science is incredible, and that is what we are trying to convey to people! Enjoy it!

This is Part 1 of a 2-part series (Part 2 can be found here), and was written as advice for speakers at the Dutch Pint of Science festival. The 2019 edition of this international event takes place in from May 20 - 22, across 8 cities in the Netherlands. The festival hosts events in 24 countries. More details about your local festival can be found here.  

Alternative medicine and cancer survival (Part 2)

My last blog post was about alternative medicine in cancer treatment. That piece was about patients who refuse all other treatment, and thankfully that is still a relatively rare occurrence. Usually, patients use alternative medicine alongside their regular treatment. As a result, studying patients who refuse all regular treatment isn't necessarily the most informative thing.Because of this distinction, researchers from Yale decided to have a look at patients who do this, and they published their results this month. It is not encouraging reading.The research showed that if patients used alternative medicine at the same time as conventional medicine, they were twice as likely to die in the 5 years after diagnosis. I will get into the details and the numbers below, but first I want to repeat that statement. If patients used alternative medicine at the same time as conventional medicine, they were twice as likely to die in the 5 years after diagnosis. That is a shocking toll.Before I get into the study itself, I want to briefly explain this result. Essentially, if someone uses alternative medicine, they are more likely to refuse other parts of the treatment. So this terrible loss of life is probably not because a specific alternative medicine was causing a problem, but because the belief in pseudoscience has corroded and undercut the public’s trust in medicine. People believe that their alternative treatment is viable replacement for conventional therapy.This belief has not sprung out of nowhere; an entire industry has been built on the idea that medicine is “toxic”, and that if something is “natural” it is automatically better for you.I know so many people who use alternative medicine, from acupuncture, to supplements, to homeopathy, and they often say “what’s the harm?”. Well, this is the harm. Because of the normalisation of this kind of thinking, patients are making bad medical decisions, and are dying as a result. I will say it again: patients who used alternative medicine at the same time as conventional medicine were twice as likely to die in the 5 years after diagnosis.So what does the science actually tell us? Research from a few years ago showed that if someone uses alternative medicine, they are more likely to skip certain parts of their treatment. However, that study didn’t look at how this impacted their survival. This new paper takes that finding and looked at a larger population of patients to see if the use of alternative medicine alongside conventional treatment had any affect (good or bad) on cancer.Firstly, the authors confirmed that in their population of patients, those who used alternative medicine were far more likely to refuse or skip part of their treatment. This included surgery, radiotherapy, chemotherapy and hormone therapy.For example, 7% of patients who used alternative medicine refused surgery, while only 0.1% of other patients did. 34% of alternative medicine using patients refused part of their chemotherapy, while only 3% of other patients did. In a way, this is understandable: these treatments are hard, and make people feel awful. If you already believe that your side effect free alternative medicine is a viable replacement for your chemo, then skipping a round of chemo doesn’t seem like that big a deal.Just to be clear, interventions like surgery, radiotherapy or chemotherapy are not used because we think they improve survival; they are used because we know it. Huge numbers of clinical trials have been done to figure out what allows patients to live longer, and these treatments do that. And refusing some of these seems to be what is doing the damage in patients taking alternative medicine.There is not much more I can really say about this study, apart from the usual caveats. A lot of patients lie to their doctors about their use of alternative medicine, so that could be a confounding factor. The authors were very strict with their criteria, so as a result, the study was relative small, with only 258 alternative medicine-using patients. That being said, it is the biggest study we have on the topic, and the analysis was very rigorous.What this study really shows is the harm that the “natural” industry is doing. Vaccination rates are falling all around the western world. Species are being wiped out because of the popularity of traditional Chinese medicine. But perhaps most damagingly, a third of the American population regularly use alternative medicine without any evidence that is has any effect, spending nearly $200 billion in the process. With such a huge number of people using it, and with the credulous treatment it receives in Hollywood and other media, it is no wonder that people assume it works. It has been marketed and accepted by a large number of people as a true alternative to medicine, and as a result, people are dying for no reason.This is why it is so important to call out pseudoscience when it comes up. We live in a world where medicine is advancing on a daily basis. We can live longer, healthier lives, but people are increasingly taking that for granted and turning towards pseudoscientific ideas, because they are more "natural". The reality is that the more people who understand that alternative medicine does nothing, the better.

Alternative medicine and cancer survival

I often wonder just how much I annoy people when the topic of alternative medicine (alt med) comes up. In general, if someone says something I don’t agree with, I let it slide. When it comes to alt med, however, I don’t seem to have the same restraint. It’s unfortunate really, as it comes up surprisingly often, and my position comes across as pretty extreme.People ask “What’s the harm?”, and point out that “Even if it doesn’t do anything, people feel better having tried it”. I empathise with this position, but completely disagree. The point I try to make is that if we accept the use of alt med, we legitimize it, making people more likely to choose it over conventional medicine.Alt med banner smallerThe focus of this post is cancer patients who put all their trust in alt med. While it's true that most people use alt med alongside real medicine, the popularity of, and belief in, the alt med movement means that it is inevitable that some people will ignore mainstream medicine in favour of alternatives.Unfortunately this does happen, and it happens regularly enough for us to study it. A few months ago, researchers from Yale published a paper looking into the outcomes for cancer patients who chose alt med over conventional treatment.The authors chose four types of cancer to look at: breast, prostate, lung and bowel. Additionally, they chose patients who had early stage disease, so had a good chance of surviving their cancer.Before I get on to the results of their study, one interesting thing to note is that the researchers show that the patients who rejected conventional treatment were more likely to be younger, healthier, more highly educated, and female. These are the patients who would be expected to have better outcomes than other cancer patients, to survive longer and to have fewer complications. However, that is not what the researchers found.Unsurprisingly, the patients who chose alternative medicine were far more likely to die from their cancer than those who didn’t. In the case of breast cancer, alt med users were nearly 6-times as likely to die. In colorectal cancer they were 5-times as likely. In lung cancer they were twice as likely. To put it simply, choosing alternative medicine above conventional therapy kills cancer patients.So, if 100 women with breast cancer were on conventional therapy, 13 would be expected to be killed by their cancer in the 5 years after diagnosis. If the same women were on alternative medicine instead, 41 of them would be expected to be killed over the same time. It is a damning example of the damage alt med can do.Alt med survivalAs always, there are a few caveats with this study. One is that these patients completely rejected conventional therapy. Patients who combined it with conventional therapy were included in the conventional arm, so this study can't say anything about the benefits/damage of that situation.It is also likely that these numbers quoted above are an underestimation. Patients who started using alternative medicine, but switched to conventional therapy (when they realise it was not working) will have been counted in the conventional therapy group, meaning that in reality the use of alt med is probably doing even more damage than described in this paper.This all brings me back to my original point. When people give alt med a sheen of validity by claiming it works, it starts to be seen as a true alternative to our tried and tested treatments. The reality is that it simply isn't. As long as it has some legitimacy, a proportion of the population will use it instead of real medicine, at best wasting money, and at worst seriously damaging their own health. I argue with people about alt med because if I don’t, I feel like I am tacitly agreeing that it has some clinical use, when I know it is not true.To paraphrase an old saying, you know what they call alternative medicine that has been shown to work? MEDICINE. And real medicine saves lives.

How improved cancer screening can make us think we are doing better than we really are

This blog post is a follow on from this post I wrote about cancer survival, and is about some really interesting quirks we encounter when we try to study it. These problems arise when we increase our ability to detect the cancer at earlier stages.

Lead time bias 

The first of these is known as lead time bias. Because of better technology, we can now diagnose cancer earlier. So imagine a case where a new screening technique lets us catch a cancer 1 year earlier. The catch is that no matter how early we catch it, in this case the disease is going to progress and ultimately kill the patient.Lead time bias with old technologySo before the introduction of this new technology the patient might only survive 1 year after diagnosis, because we are catching it late. After the introduction, we can now catch the disease early, and the patient will survives 2 years after diagnosis.Lead time bias with new technologyIf we were just looking at the numbers, we might think that we are making significant progress with this disease, because patients are now surviving for 2 years rather than just 1. However, we have done nothing to increase the patient's lifespan. If we hadn’t caught it at all, the patient would have died on the same day.This is known as lead time bias. Because we are catching a disease earlier, it can look like patients are surviving longer, when in fact they are not. It is an easy mistake to make, but a very important bias to consider when we are talking about cancer survival.

Length time bias 

The second problem appears when you realize that if we detect a cancer early, it is possible that we are detecting a cancer that might never have progressed at all. It isn't well-known, but there are cancers that never progress to a dangerous level. If we look at autopsies, nearly half of all men have prostate cancer when they die. However, only a small proportion of them actually die from prostate cancer. The rest have the cancer, but it will never progress. So the men are dying with prostate cancer, but not from prostate cancer. Most of these men will never have symptoms, so will never be diagnosed.If a patient has symptoms, then it is quite likely that the cancer will progress if we don't treat it. However, if we use a screening technology and catch the cancer before symptoms appear, then it is possible (likely) that some of those cancers were never going to progress to a dangerous level.For example, before a screening technology is developed, survival from a particular cancer might be quite low, because we don't detect the cancer until symptoms appear. Then we develop the new screening technology, and suddenly we are detecting all the cancers, regardless of whether they have symptoms or not.If we were just looking at the numbers it would look like the incidence of that cancer is increasing (we now detect extra cancers that we wouldn’t have before), but it would also look like we are successfully treating these additional patients. Even though those cancers would never progress, patients would still get (un-needed) chemotherapy, and it would look like the treatment was successful.The result of this is that we would think that the survival is increasing, but in reality, we are just identifying cancers who we wouldn’t have previously.This is just two examples, but understanding this kind of bias helps us realise just how easily we can be fooled into thinking the wrong thing. This lets you look more critically at studies, and hopefully means we are less prone to bias when carrying out these kind of studies.

Disparities in cancer survival

In my last post I published some good news about cancer survival rates, so I thought it was important to highlight a big problem with our recent success against this disease. This issue is flagged up in a study published at the end of January.It addresses the fact that the gains we have made in cancer diagnosis and treatment are very unevenly spread around the world. To analyze this is greater detail, the scientists studied the differences in survival in different countries, and the results are somewhat predictable.If, for example, you are an Australian or American with breast cancer, you have a 90% chance of surviving. If you are Indian however, you only have a 66% chance.If a child is diagnosed with acute lymphoblastic leukaemia in Finland, they have a 95% chance of beating the disease; in Ecuador, the rate is only 50%.So, over the period of this study (2000 to 2014) roughly 200,000 Indian women died from breast cancer who wouldn’t have died if they were living in the US. Almost 1,000 Ecuadorian children died from acute lymphoblastic leukaemia who wouldn’t have if they were in Finland. The same pattern is seen for all cancers, so it is clear that millions are dying from cancer in less developed countries who would not be if they were born somewhere else.This is even more staggering when you realise that this study did not even include countries at the bottom end of the global poverty index. This excluded nearly one third of the global population, as the records and reporting from these areas is just too unreliable to use.It is clear from the numbers that if you are from a less well-off country, you are far more likely to die after being diagnosed with cancer. This isn’t entirely surprising, as the detection and treatment of the disease changes quickly and can prohibitively expensive.Unfortunately, it is also likely get worse in the coming years. Due to a lack of tobacco regulation in poorer countries, lung cancer is set to increase. The WHO has pointed out that smoking still appears to be increasing in Middle Eastern and African regions, and it is known that the tobacco industry has actively been targeting young people in these countries.Additionally, as our treatments for cancer get more sophisticated, they also get more expensive, something I have written about in the past. When combined with less well supported health systems, and other more pressing public health issues, the picture looks bleak for cancer patients in many low- and middle-income countries.Of course, there are plenty of other public health improvements that can be made around the world that would have a bigger impact on people’s lives than providing better access to cancer treatments. Access to clean water, anti-malarial programs, and HIV and TB treatment programs would be far wiser investments than cancer therapeutics. However, as we in cancer research congratulate ourselves on our successes, it is always worth keeping in mind just how unevenly that success is distributed.

Are cancer rates rising?

Cancer is so prevalent in life now that it is easy to think that the rates are skyrocketing. However, the numbers don’t back this up. In actual fact, we are slowly but surely advancing our response to the disease, and recently published data underlines this progress.The publication was the annual report of the American Cancer Society. In that article, they compile all the recent data to see what trends there are in cancer rates and deaths.The report delivers some good news.Although cancer kills more people in the US than anything except heart disease, the incidence of the disease (the percent of the population diagnosed) is stable or declining, and survival is increasing. This is a steady trend we have seen over the last decade, and it looks like it will continue into the future.To be clear, because the population is increasing we are seeing more cancers, so the total number is rising, but the incidence (which is relative to the population) is not changing. For example, if there are 200 cases of cancer in a population of 100,000 (0.2%), that is the same incidence as 20,000 cases in a population of 10 million (0.2%). The number of cases is different (200 compared to 20,000), but the incidence is the same.Also remember that the older you are, the more likely you are to be diagnosed with cancer. And that people are now surviving longer with the disease than ever before. So, when this increased survival is combined with the rising and older population, it is perfectly understandable that we come into contact with more and more people who have had the disease, and thus think that the rate is increasing.What the data actually shows us is that this is not the case. In women, the overall incidence of cancer is neither increasing nor decreasing. While there are drops in colon and lung cancer, there are increases in breast and skin cancers that offset these, so overall, there is no change.In men we have also seen a drop in colon and lung cancers, but also a large decrease in prostate cancer, which means that overall, male incidence of cancer has dropped by around 2%. The decrease in prostate cancer is largely down to changes in how we screen for the disease, so is probably not a true decrease (before we changed the screening we were detecting lots of cancers that would never have progressed. We no longer count them in the numbers). In reality, the male situation is probably like the female situation, and there has been little change in the numbers.When we look at the survival from cancer, the picture is more optimistic. Since 1991, the overall death rate from the disease has decreased by 1.5% per year, which means that in the last 36 years we have seen a decrease of over 26% in cancer deaths. That means that the likelihood of you dying from cancer has drastically decreased.In 1975, 50% of patients were dead after 5 years. By 2012 this had decreased to 34%, and this trend is continuing, with more people surviving for a longer time after being diagnosed with cancer.There have been several major advances in the last few years, and we are yet to see the real benefit of these, so it looks like this trend for increased survival will continue. It is slow progress, but the numbers certainly give us cause to be optimistic!

Ultra-processed foods and cancer

This story was all over the news today:

“Ultra-processed foods may be linked to cancer, says study”The Guardian, 15th Feb. 2018

The news comes from a French study that looked into whether cancer was associated with highly processed foods. As usual, the question is whether the actual results of the study warrant the hysteria currently playing out in the media? (Spoiler: the answer to that is almost always an emphatic NO!)First things first; this is an excellent study, with well carried out data collection and good analysis of the results. The authors looked at 104,980 people, and asked them to fill out a daily survey about their diet. Using that data they compared cancer rates to the people’s self-reported diets.The study found that high consumption of “ultra-processed foods” was associated with a 12% increased risk of cancer. In men, no one cancer type was specifically increased, in older women the foods were associated with an 11% increase in breast cancer.These studies are notoriously difficult to interpret, mainly because, aside from their diet, there are numerous differences between people. In this study for example, the participants who consumed a higher amount of ultra-processed foods were more likely to be smokers, and less likely to be physically active.Clearly, what people eat is only part of a larger lifestyle. People who eat healthily tend to be healthier in other areas of their lives, so it is very difficult to say that a specific dietary choice is actually causing cancer. The authors of this study tried to correct for things like this, but that is extremely difficult to do, something that was acknowledged by the authors in their paper.It is also worth saying that the definition of “ultra-processed” is a hard one to pin down. The definition used in this study was based on a food classification system called NOVA, but this is still not very clearly defined, which means it is difficult to draw any practical conclusions from it. Unfortunately, in the media the term is wielded to mean anything that isn’t “natural”, despite this being wrong. For example, according to the classification used in this study, gluten-free artisanal bread is ultra-processed, as are vegan health shakes, and organic protein bars.While this is a solid piece of research, the public reaction to it is likely to be misplaced. Unfortunately, it is likely to play into the “clean eating” fad, which is largely nonsense. It is now clear that the fashion for “clean eating” has legitimised eating disorders, and may in fact be doing far more harm than good.However, as global consumption of processed food increases, it is very important that we understand their impact on health. This research clearly warrants more study, but these findings alone cannot offer practical advice to consumers. As always, if you have a varied diet and get a bit of exercise, there isn’t much to worry about! 

Cancer vaccine breakthrough?

Every once in a while I see a paper that makes me sit up and say “Wow”. They are rare, but when they happen they let us really see the progress that is being made. This week one of those papers was published in the journal Science Translational Medicine.The study built on recent work that is focused on the immune system, and the potential that we can make it attack a cancer (something which doesn’t normally happen). There has already been some excellent results in this field in human trials, but this study took the work in a slightly different direction. The work was carried out in mice, so is still at an early stage, but the a small clinical trial is starting this month, and that will tell us how optimistic we should be.What these scientists have developed is a clever way to activate the immune cells specifically within the tumour by injecting it with a tiny amount of DNA and another compound. When they did this they found that the tumours shrank and disappeared. It gets better though: they tried the same approach in breast cancer, colon cancer, and melanoma, (three very different cancer types) and saw the same effect across the board.Vaccine growthPerhaps the most exciting part of the work was that when they injected one tumour, the immune system attacked all the tumours in that mouse, which means that this is an approach that may work in late stage patients, who are typically very difficult to treat.The technique itself makes use of a trick that is already used in patients: by injecting a tiny amount of DNA into a patient’s cancer, we can improve responses to chemotherapy. It works by making the immune cells in the vicinity express a marker on their surface, which has the effect of priming them for action. The insight that these scientists had, was that by using a second compound to recognize this marker, they could activate the cells to attack the tumour. Because the injection is directly into the cancer, only the immune cells that recognize the tumour are activated. Some of these then leave the original tumour and attack other ones throughout the body.This approach proved to be remarkably effective. In total, the scientists treated 90 animals with the therapy. Eighty seven of those were cured. Additionally, in some of the mice the tumours became resistant and began to grow again, which is typically what happens in human patients. However, if they then injected this new tumour with the therapy, they saw the same shrinking as before, which is extremely encouraging.It was a startlingly successful study, but as I mentioned above, this work was in mice, so we can’t be sure the results will translate to humans. It’s possible that there will be toxicity to humans, or that there will be issues with stimulating the immune system like this, but it is also very possible that we will see some real benefits of this therapy.It’s an exciting time to be in cancer research!

Does a common drug increase stomach cancer risk?

This story was in the papers this week, linking a very commonly used medication with a doubling in stomach cancer risk. A doubling in the risk of anything sounds bad, but what does it mean in reality?

“Acid reflux drug linked to more than doubled risk of stomach cancer”

Acid refluxThe scientists, working in London, published a paper linking the use of proton pump inhibitors (PPIs) with cancer. As around 20 million people in the US take these drugs annually, usually to deal with heartburn, it is obviously very important to be aware of any potential harm they are doing. Indeed, several recent reports have emphasised that these drugs are not as safe as their maker’s say, although the levels of side effects is admittedly extremely low.This study found an increased risk of stomach cancer in people taking the drugs. Those on PPIs were 240% more likely to be diagnosed with the disease. However, to understand this properly, you have to realise the difference between relative risk (which this is) and absolute risk.For example, this increase in relative risk of 240% actually means an increase from 0.24% to 0.57% in the chances of an individual patient getting the disease. In other words, the likelihood of you being diagnosed with stomach cancer goes from a low risk to a slightly less low risk. So of the over 60,000 people included in this study, PPI use was associated with an extra 10 cases of stomach cancer. Most people would consider this acceptable for the benefit they get from the drug.While the increased risk for an individual is low, these drugs are among the most commonly prescribed in the world, as I mentioned above. So, for a population this big, a small increase in risk can result in thousands of additional cases of this disease.Extrapolations like this have to be taken with a pinch of salt however, as they are fraught with issues. For one thing, the study only followed people for 9 years, so it’s difficult to say much about a population of people taking the drugs. Most importantly however, these extrapolations make mass generalisations. Not all patients will be long-term users, while some will be on the drug for longer than the 9 years of the study. It is pretty clear however, that PPI use is associated with many additional cases of stomach cancer.It has to be pointed out though that this is a correlation, and we cannot say that the PPIs are causing the increase. I’ve discussed this in the past here, so I won’t go into detail on this.One last thing to mention is that although PPI use has increased dramatically since they were introduced in 1988, the number of stomach cancer cases has decreased by over 25% in the same time, due to other preventative measures we have put in place. This downwards trend is still continuing, so we can expect further drops in the coming years. Absolute risk v relative riskI showed above that even a large increase in risk of stomach cancer doesn’t mean many extra cases, and I have previously discussed the difference between absolute and relative risk in this blog post.Have a look at the diagram below. In both situations you have a 100% increase in relative risk. However, in one case this means your absolute risk goes from 1% to 2%. In the other it goes from 35% to 70%. Understanding this difference lets you be a lot more critical when reading numbers in the media!Relative v absolute

Vitamin supplements: unexpected consequences

Over the last number of years, the vitamin and nutritional supplement market has grown phenomenally. It is estimated to be worth over $36 billion in the US, up from $17 billion in 2000. It is thought that nearly 70% of the US population take some kind of dietary supplement, and there is much said and written about their use. One thing that cannot be debated however, is the lack of evidence that they do any good. A prime example of this comes from a study published recently about vitamin B supplements.Vitamin BThe study looked at vitamin B use and lung cancer. They decided to do this because a previous study had reported an increase in these cancers in people taking vitamins B12 and B9, but that study wasn't designed to look specifically at this, so more work was needed.This study looked at over 77,000 people between the ages of 50 and 76, over a number of years. The results were striking. Vitamin B6 or vitamin B12 use was associated with a doubling in lung cancer risk in men, if taken at above the recommended daily allowance. Since people generally have no idea what the recommended daily allowance is, and the levels of these vitamins can be very high in supplements, there may be many people putting themselves at risk. Indeed, the majority of people taking vitamins unknowingly exceeded the recommended daily allowence.There are a few details that are worth noting. First, the effect was only seen in men and not in women. Second, the association was even stronger in smokers, who are already prone to lung cancer. Third, this effect was present for B6 and B12, but not for people taking B9 (also known as folic acid). Finally, the authors found no beneficial effects of vitamin B supplements in any group.So what does this mean in real terms? Of the 37,049 men in this study, 1966 where found to be taking the highest dose of vitamin B. Of that 1966, 36 were ultimately diagnosed with lung cancer. If they had not been taking vitamin B supplements, this would be expected to be 18 lung cancer diagnoses. That suggests that high vitamin B use was associated with roughly an additional 18 cases of lung cancer. When you consider that this study had over 77,000 people enrolled, 18 additional cases of lung cancer may seem quite small, and these numbers are indeed dwarfed by the additional cases caused by smoking, but it is still significant.As always, I have to point out that this study did not show that vitamin B supplementation caused these extra lung cancers, just that men taking high doses were more likely to get it. As I have previously described, correlation is not the same as causation. However, this was a well carried out study, and the authors controlled for as many variables as they could, making it more believable that the vitamin supplementation is contributing to the cancers.What is clear however, is that vitamin B pills give no benefit on any health outcome. Considering that they may even be doing some harm, it emphasises that we should be cautious when supplementing our diet with unnaturally high levels of vitamins. It is generaly assumed that the more vitamins the better, but as this study points out, that is not the case. A healthy, varied diet more than meets our vitamin needs. Why spend money on supplements if we don't need them?

Is coffee bad for you?

People have an undying love for coffee. Around the world, it’s estimated that 2 billion cups are drank every single day. Lots of people can’t start the morning without one, and there’s now a coffee shop on every corner in every city. COFFEEConsidering this popularity, it is perhaps unsurprising that the health benefits/health damaging effects of coffee are never far from the news. This year alone has seen 25 different articles on the Daily Mail Online, detailing why the drink is going to make you live longer or shorter, depending on the article. Of those 25, 14 were extolling the benefits of coffee, while 11 were describing the opposite.On one particularly impressive week the site published six separate articles on the topic, claiming among other things that coffee is nature’s Viagra, that it protects against liver cancer, and that it can cause miscarriage and birth defects. If you were to ask somebody whether coffee was good or bad for them, I sincerely doubt that they would know. So what does the evidence say?Quite a lot actually. There have been many studies on the role that coffee may play in different diseases, which I will get in to below. As is almost always the case however, the first thing to say is that there’s probably no need to change your habits. Whether coffee is good for you or bad for you, the effect seems to be minor. If you love your coffee, there’s no need to cut back. If you’re not a drinker, there’s no need to start.Before I get into the health implications of coffee, it is worth mentioning that aside from the drink itself, people should really think about the way they drink their coffee. It is thought that at least 58 billion paper cups are thrown away each year, made from 32 million trees, and requiring a staggering 100 billion litres of water for their production. It is an extraordinarily wasteful industry, and something as simple as buying a reusable cup can make a significant difference, particularly if it is not made from plastic.Latte Food Background Wood Espresso CoffeeBelow I have described what the current literature has to say regarding coffee consumption and various diseases. Ultimately, it is safe to say that for a healthy person with no underlying conditions, normal coffee consumption is probably good for you. The benefit is small in all cases, so it is not something to worry about. As always, there are caveats involved (whether you take sugar in your coffee, whether you drink decaffeinated, how hot it is when you drink it…), but I have tried to answer the major questions below. It is worth pointing out that although an individual coffee drinker is unlikely to see any benefit from their habit, due to the large number of drinkers around the world coffee drinking could potentially have a large impact on the overall health of the population.

Ultimately, it is safe to say that for a healthy person with no underlying conditions, normal coffee consumption is probably good for you.

Q: How much coffee is too much?In general, various safety authorities suggest that 2 – 3 cups of coffee in one sitting is perfectly fine, provided that people don’t drink much more than 6 in a day. For most people, 8 – 10 cups will begin to produce negative side effects, including migraine, anxiety, nervousness, trembling, insomnia and an increased heart rate. These side effects are all caffeine related, and this seems to be the main culprit in the coffee-related problems. Obviously the amount of caffeine differs in different coffee brands and brews, and the numbers above relate to roughly one shot of espresso per cup. There has not been any study confirming or refuting long-term detrimental side effects of regularly drinking more than 6 cups per day (apart from extreme cases when people far exceed this), so we can’t really say either.A: 6 cups seems to be the recommended daily limit for a healthy person, but this is largely precautionary. Q: Does coffee change your risk of dying?The simplest thing we can look at is whether coffee makes you live longer. There have been numerous studies into this, and their results have been mixed. It is pretty clear that coffee doesn’t in general shorten life. Several studies have found no correlation between coffee consumption and longer life, however some have found the opposite. The most recent work I could find suggests that those drinking more than 4 cups a day were at a lower risk of dying, however this was only true in people over 45 years of age. This work was presented at a conference and has yet to be published, so I haven’t been able to have a look at their analysis. However, confusingly, other studies have found that those who drink small amounts of coffee (1 cup a day) get a benefit, but that benefit disappears if you drink more than 4 cups. Some studies claim that women benefit more than men, and others that the benefits depends on what ethnic group is being studied. All in all, the literature is mixed, which is a clear sign that if there is an effect, it is a tiny one. It is interesting to note though, that the scientists who carried out the most recent study found that even people who drank decaffeinated coffee got some of this benefit, meaning that the effect may only partially be as a result of caffeine intake.A: Coffee may extend life in certain circumstances, but if it does, the effect is tiny. Q: Are coffee and cancer associated?As coffee drinking and smoking often went hand in hand in the past, it is difficult to separate the two in studies. What is clear is that the results are mixed. A Japanese study suggested that high coffee consumption (over 5 cups a day) had a protective effect. Another recent analysis suggested that coffee is not associated with the large majority of cancers, with a few exceptions. Coffee seems to have a protective effect against liver cancer, but the size of this effect is debatable. However as most liver cancers are related to either smoking or obesity, there are far bigger interventions that can be made to protect against this cancer. There have been studies showing a slightly reduced incidence of endometrial, skin, gallbladder, oral, and kidney cancer in coffee drinkers, but these studies have yet to be confirmed. Finally, there was a suggestion that coffee drinkers were more prone to prostate cancer, but recent studies have cast doubt on this.A: Coffee seems to have a protective effect against liver cancer, and potentially against several others. Q: Does coffee affect heart health?It was thought for a long time that coffee was associated with cardiovascular diseases, hypertension, and heart failure. This makes intuitive sense; when people have too much coffee, they often feel like their heart is racing. Several studies seemed to show this was the case, however none of the studies were thorough enough to tell for sure. More recent studies have shown that this is not the case, and that coffee has either a neutral or a beneficial effect on heart health. For example, some studies show that coffee is protective against coronary heart disease in women, and reduces the risk of death in patients who have had a heart attack. Other studies show no change or an increase in coronary heart disease risk, so any effect is likely to be small.A: Coffee has a neutral or slightly beneficial effect on heart health. Q: How about the effect of coffee on mental health?The number of studies looking at this is smaller than in the previous paragraphs. However, those that have been done do show that coffee has a slight protective effect on depression risk, although some of those studies were of poor quality. Due to the sleep disturbing effects of excess caffeine, there is reason to think that this may also have a detrimental effect on mental health, but the evidence has not backed this up.A: Coffee seems to have a slight beneficial effect on mental health Q: Does coffee play a role in neurodegenerative diseases like Alzheimer’s and Parkinson’s?Lifelong coffee consumption seems to have a protective effect on the development of Alzheimer’s and Parkinson’s. In both cases the effect was more pronounced in the early stages of the disease, and in the case of Parkinson’s, it the effect was bigger in men than in women.A: Long-term coffee drinking has a slight protective effect in age-related dementia Q: Does coffee protect your liver?It is in liver disease that we see the biggest protective effect of coffee. Liver enzymes tend to be lower in coffee drinkers (which is a good thing). Interestingly, this tends to be more pronounced in patients at the highest risk of liver disease, such as alcoholics. It is also beneficial in non-alcoholic liver disease and other metabolic syndromes. Coffee inhibits the Hepatitis C virus, and drinkers show lower levels of damage in their livers, and as mentioned above, coffee seems to have a protective effect against liver cancer.A: Coffee has a slight but significant protective effect against almost all kinds of liver disease and damage Q: Does coffee affect fertility?There is very little evidence that coffee consumption has a measurable effect on fertility. Several studies have shown a slight decrease in semen quality with high caffeine intake, and others show a very slight increase in the time to pregnancy for caffeine drinkers. This study included energy drink consumption have far higher levels of caffeine than coffee, so the results were probably skewed by that population. Several larger studies have found no correlation between coffee consumption and an increased time to pregnancy.A: Coffee drinking does not decrease fertility. Q: Is coffee safe in pregnancy?Many women avoid caffeine during pregnancy, preferring to err on the side of caution in this case. The WHO recommends limiting caffeine intake during pregnancy to 3 cups or fewer per day, and the evidence supports this conclusion. Studies have shown that high caffeine intake is associated with a slightly higher risk of pregnancy loss and developmental defects. If drinking fewer than 3 cups per day however, there is no evidence of an increase in foetal malformation, neurodevelopmental defects, or miscarriage.A: High coffee consumption may cause issues in pregnancy, but no problems have been seen for those drinking 1 – 2 cups per day.

Anti-obesity campaigning and stigmatization

Last year Cancer Research UK launched the latest campaign aimed at reducing obesity related cancers. This is an important issue, with obesity now being recognised as the second biggest preventable cause of cancer, behind only smoking. The evidence for this is extremely solid, and it is expected to cause an additional 15,000 deaths in the UK from cancer this year alone. And the numbers are increasing steadily. In the 20 years from 1993 to 2013, the number of people classed as overweight or obese in the UK increased by 6 million.Looking at these numbers it is very easy to make the case that an anti-obesity campaign is a perfectly acceptable, indeed necessary, part of our strategy to tackle cancer. This was the logic behind the CRUK campaign. However, that initiative was badly received by some people, who described it as “fat phobic” and very insensitive. These objections are easy to dismiss, especially when viewed alongside the obesity related cancer statistics. However, rather than immediately rejecting these arguments, it may be worth considering them for a minute.Let’s get a few things clear first.

  1. Mental health problems are extraordinarily common and are a huge problem for us as a society. For example, it is thought that 25% of the population will experience mental health issues each year, with the OECD estimating an annual cost to the UK economy of £70 – 100 billion (around €80 – 115 billion). Several reputable sources put the cost as even higher than that. As a comparison, the economic cost of cancer is “just” £15.8 billion (around €18 billion), emphasising just how important an issue mental health is.
  2. Negative body image is associated with mental health problems. Unfortunately it is an extremely complex and under-studied field, so solid numbers are hard to come by, but it is estimated that 22% of adolescents suffering with depression have clinically significant body image concerns. This does not mean that one causes the other, but it is safe to assume that our societal problem with body image is damaging.

So let's get back to cancer. The above information makes it clear that any anti-obesity campaign must balance the benefit of decreased obesity with the potential of further stigmatizing obesity and increasing body image problems. So does the CRUK campaign do this? This is an image of one of the adverts that drew the ire of body positivity campaigners.ObesityThe first question that has to be asked is what is the aim of this campaign? Obviously the charity wanted to draw comparisons between obesity and smoking, emphasising how dangerous it is. The success of the campaign relies on the assumption that people are not aware how dangerous obesity is, and on the second assumption that if they are made aware of this, people will lose weight and crucially, keep it off. It appears that the first assumption is at least partially true. While people are aware that obesity is unhealthy, less than 25% of people are aware of the increased cancer risk. CRUK have identified the need to increase awareness, but it must be pointed out that although the cancer risk is underestimated, people are already aware that obesity is dangerous.The second assumption made by CRUK is that fear of cancer will motivate people to lose weight. Scare tactics have been used in many campaigns, including well-known road safety and anti-smoking drives. The clear intention of this ad is to draw parallels with smoking, and therefore elicit the same response from people. However, there is reason to think that in the case of obesity, negative messaging may not work.A study carried out in 2012 by researchers at Yale University found that messages deemed negative or stigmatizing were seen as the least motivating of all messages. People exposed to these messages were significantly less likely to comply with their recommendations. Furthermore, there is significant evidence that making people feel stigmatized or shamed about their excess weight makes them more likely to eat unhealthily and avoid exercise, thus decreasing the effect of any public health campaign (additional published studies about this can be found here, here, here and here).The sole aim of this campaign is to highlight that obesity is linked to cancer. While this may on the surface seem like a sensible idea, unfortunately it is more likely to stigmatize obesity than have any meaningful effect on weight loss. This demonization of obesity is very prevalent, and studies have shown that society makes extremely damaging assumption about obese people, including that they are lazy, weak-willed, unsuccessful, unintelligent, lack self-discipline and have poor willpower. It is a little acknowledged but extremely prevalent form of prejudice. This stigmatization is known to be extremely damaging to mental health, but also to threaten physical health (through patient's complaints being lazily and incorrectly ascribed to their weight), to generate health disparities, and as I mentioned above, to interfere with effectiveness of obesity intervention efforts.It is clear that we need to do something about obesity. It is one of the most important health interventions we can make as a society, but increasing the stigmatization of obese people is not the way to tackle this issue. Positive, empowering messaging, healthy eating education (especially in childhood), advertising bans and facilitation of exercise have all been parts of successful anti-obesity drives in the past. Normally I think that Cancer Research UK are extremely effective in their campaigning. This time however, I think they got it wrong.

Milk and Parkinson's

As the population has been getting older, there has been increased attention paid to neurodegenerative diseases, such as Alzheimer’s and Parkinson’s. These are diseases that cause a progressive loss of mental function (dementia), or problems with movement, such as tremors. The causes of these diseases are still relatively unknown, so there is a lot of public interest in studies that look at this. This week a paper was published that suggests there may be a link between high consumption of low fat dairy (particularly milk), and Parkinson’s. This was picked up by numerous media outlets, with predictable headlines.

Do you eat 'low-fat' branded food? Parkinson’s disease could be triggered by THISThe Express, 12/06/17

It has been known for a few years that there may be a link between dairy consumption and Parkinson’s. However, this link has always been weak and controversial, so the benefits of drinking milk have far outweighed the potential harm. This week’s study took this further by analysing this link in a huge number of patients, far more than have ever been studied before.So what have they found? Well firstly, there’s no need to give up drinking milk. The study did NOT find that low fat milk causes Parkinson’s. That’s not to say the headlines were entirely wrong, but the study was not designed to find whether milk causes Parkinson’s. It was designed to see whether people who drank lots of low fat milk were more prone to the disease. This is a subtle distinction, but an important one. I have written about this in the past (correlation vs causation), but it is worth repeating. Just because two things are happening together, doesn’t mean that one is causing the other. On top of that, milk is full of nutrients, so cutting it out or the diet may have unintended consequences.This study was a big one, including nearly 130,000 people. Of those 1,036 people developed Parkinson’s over the course of the study. When they looked at how much milk these people drank compared to the rest, they found that there was no difference. However, if they specifically looked at the consumption of low fat milk, they found that people who drank 3 or more glasses per day were more likely to develop Parkinson’s. The association wasn’t very strong, with the general population having a 0.8% chance of getting the disease, and those who drink lots of  low fat milk having a 1% chance. It’s a small difference, but with an aging population, this could mean significantly more people with the disease.The authors of the paper are careful to emphasise that they are not showing that milk causes Parkinson’s. They make several alternative suggestions themselves, including the possibility that Parkinson’s itself affects dietary behaviour, causing people to drink more milk. However, it must be considered a possibility that low fat milk is increasing the rate of Parkinson’s.So is it advisable to limit your milk consumption? At present, the answer to that is no. Milk contains nutrients we need, including calcium and potassium, and has significantly less sugar than other drinks. Per glass (240ml), it has 2.6 teaspoons of sugar, compared to 5.2 teaspoons in orange juice, and 6.4 in Coca-Cola. Additionally, those at risk drank 3 or more glasses per day, which is quite a lot.In short, there is no need to start drinking black tea and putting water on your cereal. Paranoid people might want to limit their consumption to less than a litre a day, but I won’t be changing my habits on the back of this evidence!

Eggs, cancer, and motivated reasoning

The following headline in the The Daily Express caught my attention this week:

“Ovarian cancer - could EGGS be the cause of disease? Vegan charity research REVEALED”Express.co.uk 14th March 2017

The article goes on to explain that a Bristol based charity called Viva! Health has urged consumers not to eat eggs, claiming that one egg a week increases cancer risk by up to 70%. According to their own website, Viva! Health is a science-based health and nutrition charity, and being “science-based” you would expect them to have sufficient evidence to make a claim as eye-catching as the one above. So is this the case?food-eggsViva! Health claim that eggs are linked to ovarian and prostate cancer in two ways. First, the high cholesterol levels promote these cancers; and second, choline in eggs is linked to prostate cancer. They give references to scientific publications as evidence, but these publications show nothing of the sort. The journal article they point to regarding cholesterol explicitly states that any association between egg consumption and ovarian cancer risk is not due to the cholesterol in eggs. A quick look at the literature also shows that if there is any link between egg consumption and breast or prostate cancer, it is tiny. A similar pattern holds true for the link between choline and prostate cancer. The research that Viva! Health use to support their claim actually shows the opposite, that choline from eggs is not associated with cancer. It’s pretty clear, there’s nothing to worry about.It took me roughly six minutes to debunk both of these claims, using the identical publications that Viva! Health used to support their claims, so an obvious question is how a charity that clearly thinks of itself as “science-based” could come to the opposite conclusion to me. There is a well-known phenomenon in psychology called motivated reasoning. It describes a process by which someone who holds a particular belief seeks out information that confirms what they already believe, rather than rationally assessing the evidence.It is a fascinating mental trick that we are all guilty of. We all cling to different beliefs with different strengths. If I was to tell you that plastic bags are more environmentally friendly than cloth bags (unless the cloth bag is used more than 130 times), you are likely to look at the evidence and relatively quickly change your view without a huge amount of argument. On the other hand, if I was to say that immigration is economically bad for a country (or good depending on your point of view), you are far more likely to argue with me and ultimately reject that argument. Although both the plastic v cloth and the immigration arguments are contentious and depend on the studies you look at, the likelihood is that you reacted differently to each.A lot of recent research has started to dissect these distinct types of beliefs. We have normal beliefs that change with additional information, but we also have a set of beliefs that form the core of our identities. These often take the form of religious or political views, and when these beliefs are challenged we don’t take a rational approach. Instead we employ motivated reasoning, dismissing awkward facts and cherry picking the ones that agree with us. Indeed, if one of these core beliefs is challenged, it is likely that the belief will be ultimately strengthened rather than weakened by the challenge, something called the backfire effect.Motivated reasoning is extraordinarily common in pseudoscience. Topics like climate change and vaccine safety have decades of reputable research behind them, but despite this, deniers ignore the body of evidence and scientific consensus, deciding to rely on small bits of circumstantial evidence or simple untruths to “prove” their points. There seems to be very little we can do to convince people who hold these beliefs so tightly. However, the majority of the population doesn’t have beliefs like this at the core of their identity. They may have heard the arguments and be unsure about the topic, but with clear evidence and explanation, most people will make the right decisions. This is exactly why it is so important to talk about science and to educate people in how to recognize false claims.Motivated reasoning may be behind the Viva! Health claim that eggs cause cancer. They are a charity dedicated to promoting veganism, so it is entirely plausible that their beliefs regarding non-vegan foods are central to their identity. Alternatively however, they may just understand that if you link something to cancer (whether it is true or not), you are far more likely to make it into the papers, and have random bloggers talk about you!

Using stem cells to treat cancer

There are many scam artists around nowadays proclaiming the benefits of their particular unproven stem cell therapy, for anything from curing cancer to making paralysed people walk again. It’s not surprising really; stem cells are a pool of cells in every organ that are almost eternally youthful and can regenerate themselves and all other cells in the organ. They sound almost magical. However, last year the FDA (the US Food and Drug Administration) had to move to crack down on these clinics, citing the of lack of evidence that any of them work and a number of serious complications reported following treatment. Complications including patients in Florida dying, a woman developing bone fragments in eyelids following a stem cell facelift, and another developing nasal tissue in her spine after a doctor promised to cure her paralysis with stem cells.It is a field ripe for abuse partly because it is one with so much potential. Stem cells do have fascinating possible applications, and there is a lot of research going in to them at the moment. Unfortunately, most exposure people have with them is in science fiction or alternative medicine. Which is why it was very interesting to see a study published last week that underlined how much real potential this field of research has. The study used mice instead of humans, so is still at an early stage, but is very promising nonetheless.Scientists from North Carolina were studying a deadly form of brain cancer called glioblastoma (GBM), which has extremely poor prognosis for patients diagnosed with it. The work builds on the bizarre finding that these tumours somehow attract stem cells to them. So if you look at a GBM in humans, there are stem cells inside them that shouldn't be there. Scientists had previously used this fact to load some stem cells with chemotherapy and could show that in mice, the stem cells were attracted by the tumour as expected, but they could also release their therapy while they were there. The problem with this is that we have very few stem cells in the brain so finding them and loading them with drugs is very difficult.In this case the scientists overcame that problem by turning skin cells into brain stem cells. They took skin cells from mice into the lab and, because skin cells originally comes from the spinal cord which is technically part of the brain, were able to trick them into reverting back into that state. They could then give these cells their chemo payload and inject them back into the mice. When they did this the stem cells made their way to the brain and reduced tumour size to almost nothing, which is obviously a very impressive response.There are two key advantages of this approach: 1) we have lots of skin stem cells, so they are easy to get; and 2) you can do it with a patient’s own cells, meaning that you wouldn’t have to worry about rejection, which can cause severe complications. This work still has to undergo significant testing to ensure it is safe for humans, but studies so far have been positive. A group in California have carried out a clinical trial which showed that apart from tissue rejection (which isn’t an issue in this case), stem cells can be a remarkably safe form of therapy.This work is still at an early stage, but it is very encouraging. Considering that the average survival time for a patient with GBM is only a year, any new therapeutic avenues are welcome. The stem cell field is one that is on the cusp of large-scale application, and this could be one of the first in an array of new therapies for cancer and many other diseases. At present however, 95% of clinics offering these therapies are charlatans looking to make money off vulnerable people.

Does Nutella cause cancer?

nutellaOn a recent cycling trip in Canada, I ate an obscene amount of Nutella. It works as a great lunch, and dipping fresh bread in it is a delicious snack. When you are exercising all day every day, a tasty, spreadable, dippable energy source like this is extremely useful. Don’t get me wrong, it is a very unhealthy food, but despite this, I’m a fan.Which is why I was surprised this week to see Ferrero (the makers of Nutella) defending their product against claims that it causes cancer. A quick internet search revealed the problem. As the Tech Times put it: “Nutella Can Cause Cancer, Study Warns”. The Huffington Post ran with: “Stores Are Pulling Nutella After Report Links It To Cancer”, while the Daily Mail asked “Could Nutella give you CANCER?”. So what is this all about, and should you stop eating Nutella?As I’m sure you can guess, the simple answer is no, there is currently little evidence to suggest that you need to avoid Nutella. This panic was based on a study released by the European Food Safety Authority (EFSA) last year which suggested that when palm oil is refined at above 200°C, it releases something called glycidyl fatty acid esters (GE). Previous work has shown that at high levels this chemical can cause cancer in rats. Ferraro do indeed use palm oil in Nutella, so people have made an assumption that it therefore contains GE. However, Ferrero have clearly stated that they do not process their palm oil at 200°C, so no GE is produced in the process. Case closed.But for the sake of argument, lets pretend they do refine their palm oil at 200°C. Would the hypothetical amount of GE in Nutella be a cause for concern? In the EFSA report they quote the levels of GE that cause tumours in 25% of rats (10.2 mg/kg/day in case you are interested). Now obviously we would want to play it safe, and wouldn’t want to consume anywhere near that amount. So for argument’s sake, lets see how much Nutella we would need to eat to get 1/10,000th of that amount (thanks to this article for calculating the numbers). It turns out that the average adult would need to eat nearly 100g of the stuff every day to reach 1/10,000th of the amount that gives rats cancer. That’s over two jars a week, and if you are eating that much Nutella, then cancer is the least of your problems. The same amount of Nutella (800g) contains over 450g of sugar, which is double what your TOTAL sugar intake should be for a week.Simply put, concerns about cancer are a terrible reason to stop eating Nutella. Their use of palm oil has many other problems associated with it, including the devastating environmental impact, but that is another argument. As always, this is a case of poor journalism. The study itself didn’t mention Nutella, and was just focused on the GE. Some simple fact checking would have shown that Nutella does not process their palm oil in a way that produces GE, but there is nothing like a food scare to attract clicks.

Conspiracy thinking and the US election

Shortly before the election in November a story did the rounds that claimed Hillary Clinton and her former campaign manager, John Podesta, ran a child sex ring at a pizzeria in Washington DC. This was an extremely complex conspiracy theory that was based on the fact that Podesta had emailed the owner of the pizzeria regarding fundraising. And it gained a shocking amount of attention on the internet.Think about that. Millions of people were willing to share this, and numerous other fake news stories and conspiracy theories online. In fact, one of the things that defined this election was the prevalence of such conspiracy theories. Presumably only a minority of people (one hopes) fell for stories as extreme as that above, but their presence in the discourse suggests that something larger has happened. The theories may be a symptom of something else, a change in the way that people think, and it seems that Donald Trump and the Brexiteers have tapped that change to great effect.What’s going on? Conspiracy theories are undeniably popular. The YouTube channel of Alex Jones, who believes in chemtrails and that 9/11 was an inside job, has had more than a trillion video views (that’s TRILLION, with a T). These are not small numbers of people, and before you scoff and write these people off as crazies, take a minute to think about your own beliefs. Many of you on the left of the political spectrum may suspect that media sources and political parties are pawns of rich capitalists and corporations, whereas those on the right may believe that academics and liberal elites control these very same institutions.Of course, that is not to say that some of these conspiracies aren’t actually real. From Watergate, to suppression of evidence that smoking causes cancer, to the Tuskegee Syphilis experiment, history is littered with examples of real life conspiracies. Indeed generally conspiracy theories have something believable at their core, which is part of their power. Some media outlets are indeed controlled by right-wing business people, and others by left leaning business people. However, when people dismiss everything produced by a large swathe of the media, whose politics they don’t agree with, is when things get worrying.While beliefs like this about control of the media are nowhere near as extreme as the example I mentioned at the start of the article, they do indicate a specific style of thought (conspiracy thinking) that has become more and more prevalent over the last decade, ultimately contributing to Trump’s victory in November. To be clear, it is not that people all suddenly believe in conspiracies, but they do begin to see some of the same patterns that, in an extreme context, lead to that.This change in thinking has had immense effects in the last year. I will focus here on the most obvious example of this style of thought: the “that’s what they want you to think” response. A typical hallmark of conspiracy style thinking is that evidence is dismissed as part of the conspiracy. When Trump or his supporters were confronted with evidence or examples of wrongdoing, the first and biggest reaction was to blame “the liberal media”. The actual content of the criticism is ignored or not believed, and the focus is placed on the outlet providing the criticism rather than the criticism itself. It is worth pointing out that this is not something that is unique to Trump and his supporters, and seems to be happening across the spectrum. During the democratic primaries, Bernie Sanders supporters constantly criticised “the mainstream media”, preferring news from blogs and other resources.It is an extraordinarily effective response, casting doubt on all criticism. Regardless of what outlet it was, Trump’s reaction was the same. Throughout the primaries, Trump threatened to boycott the right wing outlet Fox News, saying their coverage was biased (until they swung around behind him, that is). After Megan Kelly, a Fox News anchor and debate moderator, clashed with him, he repeatedly claimed she was biased and had treated him unfairly. At no point did he respond to the content of the criticism, he instead he focused on casting doubt on her character.This narrative of a media conspiracy continued during the election, and was repeatedly deployed during the campaign. It successfully reinforced people’s mistrust in these outlets, and when combined with the echo chamber effect of social media, and the proliferation of false news, almost entirely delegitimised the press for a large portion of the electorate.This distrust extended to specialists of other sorts, driven by a systematic undermining of expertise in topics like climate change. In the brexit campaign we saw the outright dismissal of “experts”, which played to the same narrative. It is clear that this style of thinking and argument has now become mainstream, and presents a huge problem.In a way it is natural that this happened. We seem to be hard-wired to be attracted to conspiracy theories. It might be that in our past it was a good rule of thumb to see planning and malice rather than circumstance and coincidence. It may also be a coping mechanism of sorts.Psychologists have studied this type of thinking in the past. It tends to become more prevalent when people feel like they have less control over their lives, which has happened to a large portion of the American electorate as a result of economic and security uncertainties. Wage stagnation, the rise of ISIS, the undermining of knowledge and experts, and to a certain extent the revolution in the moral framework of the country (including LGBTQ rights and the role of men in society), have led to a population that feels that it has lost a certain amount of power over their own lives. This has driven people towards a more conspiratorial style of thinking. However, it is something that should be guarded against, and the recent election is a prime example of the dangers of thinking in this way.So what can be done? That is a difficult question to answer, and all we can do is guess. Trust is key; if people don’t trust the establishment and power structures, that mistrust will undermine anything that is associated with it, including legitimate enterprise and expertise. However, how you regain the trust of a population that simply doesn’t believe anything you say is anyone’s guess. The next few years will bring much introspection in this regard. Debunking the idea of a single, coordinated “mainstream media” is a good place to start, so somehow emphasising the independence of outlets may be worth doing.The constant barrage of bad news we consume certainly doesn’t help either. People feel besieged and forget that the world is actually getting better. Extreme poverty, child labour, infant mortality and violent crime are all lower than they have ever been, while education, global literacy rates and female participation in public life are all on the increase. Balance between good and bad news may help ease the sense of anxiety we have. Personally I like to think that some old-fashioned good news may help counter the idea that the world is going to shit, but then, I’m an optimist.Another tack is often taken when arguing with conspiracy theorists, and is described succinctly in the video below by Trevor Noah. The idea is that while correcting Trump with fact is obviously still important, if his supporters won’t listen to the facts it is futile. Instead you get him to elaborate, and try to get him to expose the absurdity of his claim himself. Easier said than done, but it is worth a try.https://youtu.be/9P1IVQJdVvE?t=549Obviously conspiracy style thinking is just one of a multitude of reasons that the political landscape around the world has been changing. Becoming aware of it can only be a step in the right direction.

What happens when we don't publish clinical trials

The last blog I posted emphasised the importance of publishing all clinical trials. The story of Lorcainide is a stark warning of what happens when we don’t.In 1980 a cardiologist in Nottingham named Alan Cowley carried out a small clinical trial of a drug called Lorcainide. It was known at the time that heart attacks could cause irregular heartbeats in patients (known as arrhythmia), and these arrhythmias often lead to early death. Lorcainide had been shown to suppress arrhythmia, so it made sense that patients who came to hospital with a heart attack should be treated with the drug. Cowley and his colleagues carried out a small trial with 95 patients, and tested them to see whether they were getting more or fewer arrhythmias. The drug worked, lowering the frequency of serious arrhythmia.The doctors noticed something else however. Of the 48 patients on the drug, 9 had died, compared to only 1 patient on the placebo. This was a very small trial, so the doctors weren’t overly alarmed. It’s not surprising that 10 patients died in the study; these are patients who are presenting with heart attacks after all. It was just worrying that there was such an imbalance between the groups. The doctors chalked it up to bad luck, and viewed their trial as a success.At the time, this was a perfectly valid opinion. The study had been designed to analyse arrhythmias, not look at mortality. Furthermore, it was a tiny study, so they were justified in assuming the increased death was down to chance. Unfortunately however, what happened next ensured that the importance of this study would not be recognized.The doctors wrote an article describing their findings and tried to get it published. They submitted it to three different journals, but without success.  At the same time, the company that made Lorcainide decided to discontinue it (for unrelated commercial reasons), so the doctors lost interest and decided not to publish their results.To be clear, they were trying to publish the study as a success. Lorcainide was able to decrease serious arrhythmias after a heart attack. But within the paper was the information about increased mortality, and this would have been noticed. If it had been published, the study may not have prevented prescription, but it would certainly have suggested the need for further study.Although Lorcainide was never brought to market, other similar anti-arrhythmia treatments were prescribed to heart attack patients throughout the 80s. However, in 1983 there was a review of the available literature that proposed that there was no benefit in using these drugs. The authors of that study actually suggested that there might even be increased death following treatment, but this harmful effect was too small to be sure it was real.In hindsight it is clear that this small effect on mortality was in fact bigger than was realised. That study looked at published data to come to their conclusion. However, they were missing an important clinical trial, one that was in fact sitting unpublished on a hospital desk. If they had access to this data, they may have come to a different conclusion, flagging up the danger years earlier than it was.Towards the end of the decade, after more trials were published, two studies were carried out, both of which suggested that these drugs were doing more harm than good. At this point the danger was realised, and prescriptions dropped. However, it is estimated that 20,000 to 75,000 people died every year because of the use of anti-arrhythmia medication.In 1993, 13 years after it was originally carried out, the clinical trial on Lorcainide was published. The authors pointed out that it was perfectly reasonable to assume the increased death was a matter of chance, and they are probably correct in that. Unfortunately, when they decided not to publish and leave their study to gather dust, they contributed to an unfolding tragedy. At the time, the need to publish all trials regardless of their results wasn’t appreciated, so whether they can be blamed for what happened is a difficult question. What is certain however is that as a result of not publishing hundreds of thousands of people died.Well carried out clinical trials are the bedrock of modern medicine, and unbelievably, we are still in a ridiculous situation where reporting and publishing of trials is patchy at best. Until this situation is corrected we are at risk of another catastrophe like Lorcainide. Sign the AllTrials petition here to register your support for reform.