Migraines could be a headache of the past

Is there hope for the many millions of migraine sufferers in the United Kingdom and around the world? Researchers at King’s College Hospital certainly believe that this is the case. While they are cautious about the findings of their latest research, the results certainly are one that point towards optimism for migraine sufferers.

It is estimated that the number of migraine attacks everyday in the UK number over 190,000. This figure was estimated by the Migraine Trust, and it was probably obtained by taking a sample size of the population, taking into account the number of migraine attacks experienced within that group and then multiplying it by the general population in the United Kingdom. This of course means two things: firstly, the figure was proposed by a group that has an interest in promoting awareness about migraines and is hence slightly biased, probably over-estimated. Secondly, bearing in mind that the UK population is over 66 million, and it is unlikely that the Trust surveyed 1 million people – or even anywhere near that – any differences could have been amplified by over 66 times.

What is the difference between a migraine and a normal headache? A migraine is a headache which happens frequently. Migraines themselves are classed as two types. Headaches which happen more than 15 days a month are known as chronic migraine, while episodic migraine is a term used to describe headaches which happen less than fifteen times a month.

The research uncovered that a chemical in the brain was involved both in the feeling of pain and sensitivity to sound and light. This chemical is known as calcitonin gene-related peptide, or CGRP. If CGRP is neutralised, or if part of a brain cell which it interacts with is blocked, then pain receptors are dulled and migraines are reduced.

There are currently four drug companies in the race to develop a CGRP neutraliser.

Race is an accurate term, for the company that develops and trials the drug successfully may win the patent for developing and marketing the drug over twenty years. Drug companies or pharmaceuticals are normally granted that period to reward them for the time and cost invested into research.

One such company, Novartis, trialled an antibody, erenumab on episodic migraine sufferers. Those who took part in the trial suffered migraines on an average of eight days a month.

955 patients took part in the trial and half of those who received injections of erenumab successfully halved their number of migraine days per month. 27% of patients also reduced their number of migraine days without treatment. The results suggest that the drug was successful, particularly as it worked for over 450 people, and that if it were used for those with chronic migraine it might be equally successful. Even if the same percentage were maintained (50% vs 27%), the number of working days saved by migraine prevention could have significant savings for the economy.
Another pharmaceuticals company, Teva, produced another antibody, fremanezumab, and trialed it on 1130 patients. Unlike Novartis’s trials, the participants in Teva’s were those with chronic migraine, with over 15 or more attacks each month. In the Teva trial, 41% of patients reportedly halved the number of days that they suffered migraine attacks. 18% reported the same effect, so the confidence interval in the trial is pretty high and suggests a high degree of positive use.

The study is very important and useful because of the understanding it offers in treating migraine, and the medical products can reduce the frequency and severity of headaches. It makes for fewer days lost to the disease and more positive, functioning people.

Besides CGRP antibodies, there are other current treatments for migraine such as epilepsy and heart disease pills. Even botox is sometimes used. However, all three come with side-effects and are not necessarily the best for everyone.

The hope is that CGRP antibodies, which are traditionally more expensive to manufacture, will in the long term be available at a more affordable cost, and would benefit those who currently get no benefit from existing therapies.

If the estimation that one in seven people live with regular migraine is accurate, migraine reduction could have significant life-improvement effects for humans. Chronic migraine is in the top seven disabling conditions and improvements in understanding it and how to manage it would not only improve the quality of life for those who suffer with it, but also in reducing the number of work days lost for the economy. But the benefits do not just remain with migraine sufferers. Having to live with chronic disabling conditions often leads to other symptoms such as depression. Who knows? Perhaps CGRP antibodies may even negate the effect of depression, resulting in a secondary effect. It may be possible that those who suffer from migraine alongside depression may even not require treatment for the latter if the CGRP antibodies prove to be effective.
Can you imagine a world without anti-depressants? At the moment millions live on some pain-relief medication of some sort. It would be great if they could be phased out. Although it might not be so great for the economy!

Should we be excited about the results? Well, yes. The combined large sample size of both studies, of over 2000 migraine sufferers showed that there was some weight behind the study compared to if – for example – it had been done only on one hundred participants. Secondly, while the research was undertaken by pharmaceutical companies, the outcome was actionable, meaning that it produced a result that was useful, rather than one that merely formed the prelude to a more extensive study. In previous posts I demonstrated how some – such as the coffee umbrella review – did not produce any significantly useful outcome. But we know from this particular research that it may work to neutralise either CGRP, or lessen its interaction with the particular brain cells in order to lower the effect of migraine.

Did the media have a field day with this? Unsurprisingly, no. You see, good research does not lend itself to sensationalist headlines.

The quest for fitness may be detrimental to your long term mental state

We are often told how we should aim to have, and maintain, a healthy lifestyle. After all, being physically fit allows your body to function both in physical and mental aspects. Healthy body, healthy mind, right?

The only difficulty, if you can call it that, with exercise is that the first thing that we would normally consider is running, but it is not for everyone. Going forward for a certain distance or time has little meaning for some people, especially children.

The thing about running is that it has to have some appreciable meaning, so unless you have some derivative inner joy of measuring your progress using statistics, it is unlikely to hold your interest for the long term. A better form of exercise is though group sports, as the mental boredom of tracking fitness levels is negated in favour of the social dynamic.

Common group sports such as football  have a large following in England. The football season for example lasts from August to May and provides a welcome distraction during the cold winter months. It is also a simple game that can be improvised using other materials and played on all surfaces. No goalposts? Use bags or some other markers. No football? Use a tennis ball. It is often interesting to see children turn up at a field, establish the boundaries of play using trees and creates goalposts using caps or other loose materials and these are often sufficient for the game; at least until there is discussion about whether the “ball” hit the post or went in the goal after it flies over a set of keys intended to represent the goalpost.

There is increasing concern about the link between dementia and football. The pounding of the ball against a soft surface of the brain, when the ball is headed, over time can cause the destruction of cells and cell function. This is of particular concern in the case of children, whose brains and bodies are developing. This has been of significant interest as members of England’s 1966 World Cup winning squad have found to have developed dementia in their later years. Some of them cannot even remember being there in 1966!

It is not just the impact of ball on head that is concerning, but when the head is moved through a range of motion too quickly. Even though there is no impact on the head externally, internally there is damage as the brain is hitting the sides of the skull supposed to protect it.

It is not just football that we have to be concerned about. There is plenty of head and neck related impact in rugby and American football. In fact, in American football, the head related injuries for offensive and defensive linemen, who every forty seconds start a play by ramming into the player on the opposite side of the line,  and the list of dementia sufferers is growing continually. Some players have even sued the NFL for injuries suffered during the game.

Will the rules of football change so that heading the ball is banned? Don’t bet on it. That would change the fabric of the game so much as to ruin it. When the ball is swung in from a corner, what would you do if you couldn’t head it? The game will not change, but also don’t rule out a consortium of players in the future filing lawsuits for work-related injuries. Perhaps in the pursuit of fitness, it may be wiser to choose less impactful activities for the sake of long term health.

Night time eating? Heart disease coming

That late night snack may be comforting and the perfect end to a day. However, if research is proven to be right, it could be the cumulative cause of heart disease.

Scientists have always known that night shift workers are at greater health risks than workers who work regular patterns. Which is why if you divided the pay shift workers receive by the hours worked, you would find that they have a higher hourly rate compared to those who do the same job during normal hours. That extra pay is to compensate for what is commonly perceived as the extra demand of working during the night, at a time your body is looking to shut down for a rest. The external pressures of going against your body, over a prolonged period, can exert a toll on the body.

Scientists in Mexico researching the links between diet and the human body tested their hypotheses on rats. The rats were fed food at a time when their bodies would normally be at rest, and the results showed that the fats from food remained longer as triglycerides in the body’s bloodstream for longer, because their bodies were at a resting state and not primed to break down food.

Bearing in mind that the research was done on rats, and while some results may have bearing on humans and some may not, what points could we take from these research results?

Having high levels of triglycerides in one’s body means that the risk of cardiovascular diseases such as heart attacks are significantly increased. Hence, if you are eating late at night, you may be at greater risk. Although the research is only at its infancy, they could suggest that the body is better when it comes to the processing of fats, when it is at its most active state, as it comes at more of a natural time.

What can you do if you work shifts? You may not have much control over the food you eat, but you can take steps towards eating a healthier diet and make time for regular exercise so the overall risk of heart disease is lowered. And if you do not work shifts, but work during the day, a big meal late at night is also best avoided for you.

Pressures faced by the NHS

The good news is that every day, the vast majority of the 63.7 million people eligible to use the NHS, don’t need to. And every day you don’t need to use the NHS, someone else benefits. Most people are very capable of looking after themselves most of the time, self-treating for minor ailments and knowing when and where to seek help for serious illness. 90 per cent of symptoms are self-treated but an estimated fifty-two million visits to general practice each year are still for conditions that would get better with time. Self-care is likely to improve further when those who want it are given access to and control over their medical records and data, and technology is better used to direct you to the right information when you need it. In the meantime, a friendly pharmacist can often save you a trip to the GP.

The bad news is that demand in many areas outstrips both the supply of services and the funding for them. Patients who need care are having to wait longer for it, and too many referrals are rejected as not urgent enough, when the NHS should be doing its utmost to prevent emergencies.

There is a very, very big mental illness iceberg out there and it’s showing no signs of melting.

Life is tough enough for NHS staff, but imagine what it’s like for these children and their carers who can’t get any care at all? The pattern of services struggling – or simply not being able to cope safely – with the demands placed on staff is common across the NHS. Waiting times are creeping up, emergency departments are overflowing, people struggle to get a GP appointment, services are being restricted and rationed and lots of people are having to fend for themselves.The technology and choices patients now face can be very complex, but the strength of the NHS lies in its humanity and the ethos that as a society we should pool our resources to care for and protect the most vulnerable.

The NHS is nearly always buckling under the demands placed on it, partly because it’s a victim of its own success. Improvements in public health, wealth and healthcare since the NHS was founded sixty-seven years ago have been stunning. In 1948, half the population died before the age of sixty-five. Now, the average life expectancy is over eighty. One in three children born today will live to one hundred, but one in four boys born in Glasgow still won’t make it to sixty-five. The UK is still a very unequal society, and the rich not only live fifteen years longer than the poor, but they have up to twenty years more healthy living. Life is very, very unfair, which is why we need to fight poverty and build the confidence, courage and resilience in our children to live well, as well as improve and fund the NHS. Those who pay for it most often use it least. It’s the badge of honour for living in a humane society.

And we nearly all need it eventually if we want help or treatment. One in two people in the UK will get cancer, one in three will get diabetes and nearly everyone will get heart disease. Many of these diseases will be contained rather than cured. Obesity appears unstoppable. Liver disease, kidney disease, lung disease, musculoskeletal disease, depression and anxiety are all on the increase. Mental illnesses cost the UK over £70 billion a year, one in three of us experiences mental health problems every year and one in three people over sixty-five will die with dementia. Many people with dementia live for many years, even if they haven’t been diagnosed and treated. Dementia alone already costs the economy more than cancer and heart disease put together.

These chronic diseases account for 70 per cent of the NHS budget, although many can be delayed if not prevented by a healthier lifestyle. Those with three or more incurable diseases are usually on multiple medications, the combined effects of which are unknown. Many older patients on multiple drugs struggle to take them properly, and there’s a delicate balance between benefit and harm. Loneliness is often a far bigger problem.

The NHS and social care system is crucially dependent on millions of unpaid volunteers and carers, and many very dedicated but poorly paid care workers. The round-the-clock pressures and responsibilities they face are huge. If carers went on strike, the NHS and social care service would collapse overnight. Keeping it all afloat is a massive, collaborative effort and we are far too reliant on institutionalized care, rather than supporting people in their homes.

More women give birth in hospital than need or want to be there, so those who really need to have hospital births don’t always get safe care. Far too many frail elderly patients, many with dementia, end up in acute hospitals, often the most frightening and disorientating place they can be. Far too many people with mental illness end up in police custody and far too many people die in hospital when they want to die at home. We can change this, if services join up, and patients and carers receive the right training and support. Having chemotherapy or dialysis at home can transform not just your healthcare but your whole life. It doesn’t happen nearly enough.

Fixing the NHS and social care system will not be quick or easy, even if we put more money in. In many instances, it would often be kinder to have less high-tech, expensive intervention than more. If all we ever did in the NHS was capture the ideas and feedback from frontline staff, patients and carers, and use it to continuously improve a stable system that everyone understood, the NHS would be out of sight as the world’s best. We have to spend every available penny supporting and joining up the frontline – the NHS is not about the bricks and mortar, it’s about mobilizing and motivating a brilliant workforce to serve patients and give you as much control as you want over your care. And to do that, you need to find your voice and we need to listen to you.

Research done by the Health Foundation, When Doctors and Patients Talk, found that NHS staff are often as anxious and fearful as you are during consultations. They are anxious and frightened of missing an important diagnosis, not being able to give patients what they are entitled to, not being able to practise the standards of care they’d like to, having to deal with justifiable anger, missing a target they have been ordered to hit, being asked to do something they do not feel competent to do, or having to look after so many patients in such a short space of time they just do not feel safe. The ever-present fear is that they simply cannot cope safely with the demand. Just as we shouldn’t blame people for being ill or old or overweight, we shouldn’t blame NHS staff for not being able to always provide the highest standards of care. Praise, kindness and understanding are much better motivators.

And there’s plenty to be thankful for. The Commonwealth Fund in America compares the health systems in eleven countries and ranks them according to eleven measures: quality of care, effective care, safe care, coordinated care, patient-centred care, access, cost-related problems, timeliness of care, efficiency, equity, and healthy lives. You might expect Austria, Canada, France, Germany, the Netherlands, New Zealand, Norway, Sweden, Switzerland or America to thrash us. In fact, the 2014 ranking (based on 2011 data) puts the UK top of the healthcare table overall, and first in eight of the eleven categories. It came second in equity to Sweden, and third behind Switzerland and the Netherlands for timeliness of care. The NHS is far from perfect, but we should celebrate and publicize the amazing care it often gives, try to improve the good care it usually gives and quickly address the poor care it occasionally gives, so further harm is prevented.

To improve, the NHS needs to be simplified so that anyone can understand it. We pretend to distinguish between healthcare and social care, but it’s all ‘care’ and it should be joined into one care system, with those with the greatest need treated by one team with one named person responsible for coordinating your care. And we must all do everything we can to live well. In the NHS, the staff spend too much time diving into the river of illness, pulling people out and trying to put them back together that no-one has time to wander upstream and look at who’s pushing you in.

Media’s Marvellous Medicine

When it comes to our health, the media wields enormous influence over what we think. They tell us what’s good, what’s bad, what’s right and wrong, what we should and shouldn’t eat. When you think about it, that’s quite some responsibility. But do you really think that a sense of philanthropic duty is the driving force behind most of the health ‘news’ stories that you read? Who are we kidding? It’s all about sales, of course, and all too often that means the science plays second fiddle. Who wants boring old science getting in the way of a sensation-making headline?

When it comes to research – especially the parts we’re interested in, namely food, diet and nutrients – there’s a snag. The thing is, these matters are rarely, if ever, clear-cut. Let’s say there are findings from some new research that suggest a component of our diet is good for our health. Now academics and scientists are generally a pretty cautious bunch – they respect the limitations of their work and don’t stretch their conclusions beyond their actual findings. Not that you’ll think this when you hear about it in the media. News headlines are in your face and hard hitting. Fluffy uncertainties just won’t cut it. An attention-grabbing headline is mandatory; relevance to the research is optional. Throw in a few random quotes from experts – as the author Peter McWilliams stated, the problem with ‘experts’ is you can always find one ‘who will say something hopelessly hopeless about anything’ – and boom! You’ve got the formula for some seriously media-friendly scientific sex appeal, or as we prefer to call it, ‘textual garbage’. The reality is that a lot of the very good research into diet and health ends up lost in translation. Somewhere between its publication in a respected scientific journal and the moment it enters our brains via the media, the message gets a tweak here, a twist there and a dash of sensationalism thrown in for good measure, which leaves us floundering in a sea of half-truths and misinformation. Most of it should come with the warning: ‘does nothing like it says in the print’. Don’t get us wrong: we’re not just talking about newspapers and magazines here, the problem runs much deeper. Even the so-called nutrition ‘experts’, the health gurus who sell books by the millions, are implicated. We’re saturated in health misinformation.

Quite frankly, many of us are sick of this contagion of nutritional nonsense. So, before launching headlong into the rest of the book, take a step back and see how research is actually conducted, what it all means and what to watch out for when the media deliver their less-than-perfect messages. Get your head around these and you’ll probably be able to make more sense of nutritional research than most of our cherished health ‘gurus’.

Rule #1: Humans are different from cells in a test tube
At the very basic level, researchers use in-vitro testing, in which they isolate cells or tissues of interest and study them outside a living organism in a kind of ‘chemical soup’. This allows substances of interest (for example, a vitamin or a component of food) to be added to the soup to see what happens. So they might, for example, add vitamin C to some cancer cells and observe its effect. We’re stating the obvious now when we say that what happens here is NOT the same as what happens inside human beings. First, the substance is added directly to the cells, so they are often exposed to concentrations far higher than would normally be seen in the body. Second, humans are highly complex organisms, with intricately interwoven systems of almost infinite processes and reactions. What goes on within a few cells in a test tube or Petri dish is a far cry from what would happen in the body. This type of research is an important part of science, but scientists know its place in the pecking order – as an indispensable starting point of scientific research. It can give us valuable clues about how stuff works deep inside us, what we might call the mechanisms, before going on to be more rigorously tested in animals, and ultimately, humans. But that’s all it is, a starting point.

Rule #2: Humans are different from animals
The next logical step usually involves animal testing. Studying the effects of a dietary component in a living organism, not just a bunch of cells, is a big step closer to what might happen in humans. Mice are often used, due to convenience, consistency, a short lifespan, fast reproduction rates and a closely shared genome and biology to humans. In fact, some pretty amazing stuff has been shown in mice. We can manipulate a hormone and extend life by as much as 30%1. We can increase muscle mass by 60% in two weeks. And we have shown that certain mice can even regrow damaged tissues and organs.

So, can we achieve all of that in humans? The answer is a big ‘no’ (unless you happen to believe the X-Men are real). Animal testing might be a move up from test tubes in the credibility ratings, but it’s still a long stretch from what happens in humans. You’d be pretty foolish to make a lot of wild claims based on animal studies alone.

To prove that, all we need to do is take a look at pharmaceutical drugs. Vast sums of money (we’re talking hundreds of millions) are spent trying to get a single drug to market. But the success rate is low. Of all the drugs that pass in-vitro and animal testing to make it into human testing, only 11% will prove to be safe and effective enough to hit the shelves5. For cancer drugs the rate of success is only 5%5. In 2003, the President of Research and Development at pharmaceutical giant Pfizer, John La Mattina, stated that ‘only one in 25 early candidates survives to become a prescribed medicine’. You don’t need to be a betting person to see these are seriously slim odds.

Strip it down and we can say that this sort of pre-clinical testing never, ever, constitutes evidence that a substance is safe and effective. These are research tools to try and find the best candidates to improve our health, which can then be rigorously tested for efficacy in humans. Alas, the media and our nutrition gurus don’t appear to care too much for this. Taking research carried out in labs and extrapolating the results to humans sounds like a lot more fun. In fact, it’s the very stuff of many a hard-hitting newspaper headline and bestselling health book. To put all of this into context, let’s take just one example of a classic media misinterpretation, and you’ll see what we mean.

Rule #3: Treat headlines with scepticism
Haven’t you heard? The humble curry is right up there in the oncology arsenal – a culinary delight capable of curing the big ‘C’. At least that’s what the papers have been telling us. ‘The Spice Of Life! Curry Fights Cancer’ decreed the New York Daily News. ‘How curry can help keep cancer at bay’ and ‘Curry is a “cure for cancer”’ reported the Daily Mail and The Sun in the UK. Could we be witnessing the medical breakthrough of the decade? Best we take a closer look at the actual science behind the headlines.

The spice turmeric, which gives some Indian dishes a distinctive yellow colour, contains relatively large quantities of curcumin, which has purported benefit in Alzheimer’s disease, infections, liver disease, inflammatory conditions and cancer. Impressive stuff. But there’s a hitch when it comes to curcumin. It has what is known as ‘poor bioavailability’. What that means is, even if you take large doses of curcumin, only tiny amounts of it get into your body, and what does get in is got rid of quickly. From a curry, the amount absorbed is so miniscule that it is not even detectable in the body.

So what were those sensational headlines all about? If you had the time to track down the academic papers being referred to, you would see it was all early stage research. Two of the articles were actually referring to in-vitro studies (basically, tipping some curcumin onto cancer cells in a dish and seeing what effect it had).

Suffice to say, this is hardly the same as what happens when you eat a curry. The other article referred to an animal study, where mice with breast cancer were given a diet containing curcumin. Even allowing for the obvious differences between mice and humans, surely that was better evidence? The mice ate curcumin-containing food and absorbed enough for it to have a beneficial effect on their cancer. Sounds promising, until we see the mice had a diet that was 2% curcumin by weight. With the average person eating just over 2kg of food a day, 2% is a hefty 40g of curcumin. Then there’s the issue that the curcumin content of the average curry/turmeric powder used in curry is a mere 2%. Now, whoever’s out there conjuring up a curry containing 2kg of curry powder, please don’t invite us over for dinner anytime soon.

This isn’t a criticism of the science. Curcumin is a highly bio-active plant compound that could possibly be formulated into an effective medical treatment one day. This is exactly why these initial stages of research are being conducted. But take this basic stage science and start translating it into public health advice and you can easily come up with some far-fetched conclusions. Let us proffer our own equally absurd headline: ‘Curry is a Cause of Cancer’. Abiding by the same rules of reporting used by the media, we’ve taken the same type of in-vitro and animal-testing evidence and conjured up a completely different headline. We can do this because some studies of curcumin have found that it actually causes damage to our DNA, and in so doing could potentially induce cancer.

As well as this, concerns about diarrhoea, anaemia and interactions with drug-metabolizing enzymes have also been raised. You see how easy it is to pick the bits you want in order to make your headline? Unfortunately, the problem is much bigger than just curcumin. It could just as easily be resveratrol from red wine, omega-3 from flaxseeds, or any number of other components of foods you care to mention that make headline news.

It’s rare to pick up a newspaper or nutrition book without seeing some new ‘superfood’ or nutritional supplement being promoted on the basis of less than rigorous evidence. The net result of this shambles is that the real science gets sucked into the media vortex and spat out in a mishmash of dumbed-down soundbites, while the nutritional messages we really should be taking more seriously get lost in a kaleidoscope of pseudoscientific claptrap, peddled by a media with about as much authority to advise on health as the owner of the local pâtisserie.

Rule #4: Know the difference between association and causation
If nothing else, we hope we have shown that jumping to conclusions based on laboratory experiments is unscientific, and probably won’t benefit your long-term health. To acquire proof, we need to carry out research that involves actual humans, and this is where one of the greatest crimes against scientific research is committed in the name of a good story, or to sell a product.

A lot of nutritional research comes in the form of epidemiological studies. These involve looking at populations of people and observing how much disease they get and seeing if it can be linked to a risk factor (for example, smoking) or some protective factor (for example, eating fruit and veggies). And one of the most spectacular ways to manipulate the scientific literature is to blur the boundary between ‘association’ and ‘causation’. This might all sound very academic, but it’s actually pretty simple.

Confusing association with causation means you can easily arrive at the wrong conclusion. For example, a far higher percentage of visually impaired people have Labradors compared to the rest of the population, so you might jump to the conclusion that Labradors cause sight problems. Of course we know better, that if you are visually impaired then you will probably have a Labrador as a guide dog. To think otherwise is ridiculous.

But apply the same scenario to the complex human body and it is not always so transparent. Consequently, much of the debate about diet and nutrition is of the ‘chicken versus egg’ variety. Is a low or high amount of a nutrient a cause of a disease, a consequence of the disease, or simply irrelevant?

To try and limit this confusion, researchers often use what’s known as a cohort study. Say you’re interested in studying the effects of diet on cancer risk. You’d begin by taking a large population that are free of the disease at the outset and collect detailed data on their diet. You’d then follow this population over time, let’s say ten years, and see how many people were diagnosed with cancer during this period. You could then start to analyse the relationship between people’s diet and their risk of cancer, and ask a whole lot of interesting questions. Did people who ate a lot of fruit and veggies have less cancer? Did eating a lot of red meat increase cancer? What effect did drinking alcohol have on cancer risk? And so on.

The European Prospective Investigation into Cancer and Nutrition (EPIC), which we refer to often in this book, is an example of a powerfully designed cohort study, involving more than half a million people in ten countries. These studies are a gold mine of useful information because they help us piece together dietary factors that could influence our risk of disease.

But, however big and impressive these studies are, they’re still observational. As such they can only show us associations, they cannot prove causality. So if we’re not careful about the way we interpret this kind of research, we run the risk of drawing some whacky conclusions, just like we did with the Labradors. Let’s get back to some more news headlines, like this one we spotted: ‘Every hour per day watching TV increases risk of heart disease death by a fifth’.

When it comes to observational studies, you have to ask whether the association makes sense. Does it have ‘biological plausibility’? Are there harmful rays coming from the TV that damage our arteries or is it that the more time we spend on the couch watching TV, the less time we spend being active and improving our heart health. The latter is true, of course, and there’s an ‘association’ between TV watching and heart disease, not ‘causation’.

So even with cohorts, the champions of the epidemiological studies, we can’t prove causation, and that’s all down to what’s called ‘confounding’. This means there could be another variable at play that causes the disease being studied, at the same time as being associated with the risk factor being investigated. In our example, it’s the lack of physical activity that increases heart disease and is also linked to watching more TV.

This issue of confounding variables is just about the biggest banana skin of the lot. Time and time again you’ll find nutritional advice promoted on the basis of the findings of observational studies, as though this type of research gives us stone cold facts. It doesn’t. Any scientist will tell you that. This type of research is extremely useful for generating hypotheses, but it can’t prove them.

Rule #5: Be on the lookout for RCTs (randomized controlled trials)
An epidemiological study can only form a hypothesis, and when it offers up some encouraging findings, these then need to be tested in what’s known as an intervention, or clinical, trial before we can talk about causality. Intervention trials aim to test the hypothesis by taking a population that are as similar to each other as possible, testing an intervention on a proportion of them over a period of time and observing how it influences your measured outcome.