Physical and Mental Contamination

Is there a need to start worrying about your kitchen? I don’t mean in the home improvement context, never mind that the island unit is looking a bit worse for wear, and that your swanky appliances need upgrading so you can have two ovens to cook for your little army; or maybe you are thinking you could expand beyond the microwave and gas cooker. Or perhaps you are considering the option of creating an open plan kitchen. Whatever the physical changes you are considering, they are beyond the scope of discussion. Danger lurks in your kitchen.

It doesn’t come in the form of masked strangers brandishing kitchen implements. Or ruthless critics in the form of master chefs or children. No, the hidden danger in your kitchen is more subtle, more soft, yet potentially more lethal.

The kitchen sponge.

Scientists estimate that the kitchen sponge contains the highest concentration of bacteria than anywhere in the house. On the face of things, this is not an unrealistic statement. The kitchen sponge is in contact with remnants of food as it passes over the crockery and cutlery, and while the latter are clean, microscopic elements of food have merely been transferred to the sponge. And even if you take the effort to rinse out the sponge, or go a step further by microwaving the sponge, trace elements of food bacteria will remain.

According to the Mail Online, one of the more sensationalist newspapers in the United Kingdom, there are 54 billion cells of bacteria residing on the humble sponge. But of course the Mail Online would say that – it is taking a simple fact and blowing it out of proportion in order to create a purchasing headline. (And what is a purchasing headline? It is one that intrigues you enough to make a financial physical purchase to discover more, or hook you in enough to commit your time to reading more, never mind that the headline was slightly manipulated in the first place.) The fact is, bacteria exist all around us. They are on the surfaces of things around us. But it is important to distinguish between good and bad bacteria. The majority of bacteria around us are harmless. The remaining bacteria can do us harm if they enter our bodies, which is why it is a good idea to wash hands before eating. This ensures the harmful bacteria on our hands, either from touching door knobs or taps or other contaminated surfaces, does not rest on food that we ingest. It is also a good idea to cover up exposed cuts so that bacteria does not enter the bloodstream.

Bacteria is all around us but we can’t live life in fear of it.

Can you imagine if the word bacteria was substituted with the word humans? It would give a better perspective.

The headline would read that something like “A higher concentration of criminals found in [name of city]”. But you can’t live like every human in that city will do you harm. You can only take necessary steps to avoid being negatively affected.

Just like bacteria.

The current guidelines around hand washing recommend that we  our hands with water and soap for at least 20 seconds, after instances such as using the toilet, handling raw food like meat and vegetables. It is advised that we wash our hands before eating or after contact with animals.

Does washing with specialist soaps make any difference? A study by Rutgers University and GOJO Industries in the US found that there was little difference, which suggests the science between Brand X and Brand Y is as manufactured as the products themselves.

The study involved twenty volunteers and examined variables of hand washing such as brand, volume and time elapsed. A non-harmful strain of the bacteria e-coli was placed on the hands of the volunteers and then examined after washing to see how much remained.

The study found that there was little to distinguish between normal soaps and anti-microbial formulations. In fact, as long as volunteers washed their hands with soap for thirty seconds, the difference in results after washing were negligible.

There were a couple of minor limitations to the study conducted by Rutgers and GOJO Industries.

Firstly, that sample size is too small. Secondly, volunteers could not ethically be asked to handle deadly bacteria so the results may have only be applicable to that particular strain of bacteria.

There was a major stumbling block to the research however. GOJO Industries manufactures hand soaps.

We have already examined in the past how it is not a good idea if pharmaceutical companies run their own tests because the authenticity cannot be guaranteed completely if there is a bias from the outset. If a pharmaceutical company or any other manufacturing company is going to invest time, money and effort into production, it is going to choose results which have a positive bias, rather than those with a negative one which either force further research, impacting on production time and costs, or one that cause the complete abandonment of results.

Is there anything we can trust anymore? The dilemmas we have are that the media distorts reporting, and research is funded with an agenda which produces an expected outcome. It is difficult to secure funding for research if there is no meaningful purpose behind it beyond sales.

Returning to the original issue of bacteria, as long as we take necessary precautions, that is the best we can do. These precautions include replacing the sponge regularly, and not leaving unwashed dishes in the kitchen, and washing our hands to avoid contamination.

And take in what you read and hear about health and news with a pinch of objectivity. Avoid contaminating your mind too!

Set aside time and space for your own mental health

Work places huge demands on modern living. It goes without saying that over generations work demands have increased. For example, generations ago the concept of a traditional job for most people was a five-day working working week. The song “9 to 5” by Dolly Parton more or less captured the essence of work at the time. (Unfortunately, it is still fairly often played, to the point that people in non-Western societies assume we still only work eight hour days, five times a week, and spend our free time sunning ourselves on the beach.) Nowadays people have to work longer hours, and travel further for work. The total time spent each day traveling and working each day could easily amount to twelve hours, and it is not like the commute is down time – we still have to catch up on emails, admin, and type away busily on the laptop. We could easily spend sixty hours doing work-related things.

And the weekends? Forget the weekends. These days there is no distinction between a weekday and a weekend. Work has steadily grown its talons and where an hourly-rated individual used to get 1.5 or two times the normal rate for working on a weekend, these days it is the same. Employers realise that in an economy with job shortages, they can get away with offering less rates but will not be short of takers.

The problem with all this is that we don’t really have much of a choice when it comes to establishing our work boundaries or exercise or rights when we realise we are being pushed beyond our work boundaries. We’re made to feel that in these times, we are lucky to hold down a job, and if we complain about the increasing demands of it, and how higher managers try to force more work on us without increasing our pay, we might get told to take a hike and end up in a more difficult situation of having no job, commitments to uphold and having to start out again. There are lots of people trapped in jobs where they have to take on more and more as the years go by, and have every ounce of work and free hour extracted from them for little pay. This places increasing mental demands on the individual not just in having to cope with work demands, but the possibility of being made redundant if he or she shows weakness by having to admit an inability to cope any more. It is a no win situation.

Is it a surprising statistic that mental health illness is on the rise? Hardly.

Nowadays people are working more to live and living to work more.

What can you do to preserve some semblance of mental health?

The first thing you can do for yourself is to establish boundaries within the home. Establish a space where work does not intrude. A good idea is often the bedroom, or even have a rule that you will not work on the bed. If you end up working on your laptop in the bed, it will not do you any good – keep at least a certain physical space for yourself.

Also try to set aside a time each day for yourself if possible. It is possibly unrealistic to say an hour each day in the modern life climate, but something like twenty minutes to half an hour would be a good idea. Use this time to wind down in your personal space doing something you enjoy, that is different from work. You may think you cannot really afford that time, but it is important to disassociate yourself from work for the sake of your long-term longevity. Think of it as enforced rest. If it works better for you, take your enforced in the middle part of the working day. You don’t necessarily have to be doing something, use it to rest or catch a power nap.

Every now again, such as on a weekend, do something different from work. Do a yoga class, learn an instrument like the piano, or play a game of tennis. The possibilities for leisure are endless. But don’t bring your work approach to your leisure. Don’t start charting your tennis serve percentage, or do anything that makes your leisure activity appear like work in a different form. The only thing you must do with a businesslike approach is to meet this leisure appointment so that your life does not revolve around a continuous stretch of work.

We can moan about it but the nature of work will never revert back to how it was in the past. Those of us who long for the good old days will only make our own lives miserable with wishful thinking. Those of us who insist on working five-day weeks will find it is insufficient to maintain modern living in the twenty-first century. We will all end up working longer and harder in the current economic climate, and even if times improve, employers will be unlikely to go back to pre-existing forms of remuneration if workers have already been accustomed and conditioned to work at a certain level, because it is more cost effective to hire fewer employees who do more work than have the same work done by more employees. Employees have to recognise that adapting to increasing work loads are a working life skill, and that taking steps to negate increasing pressures will also be an essential part to maintaining our own mental health and well-being.

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.

Why mental health problems will never go away

Many people will experience mental health difficulties at some point in their lives. As people go through life the demands on them increase, and over a prolonged period these can cause difficulty and ill health. These problems can manifest themselves both in mental and physical ways.

What kind of demands do people experience? One of these can be work-related. People may experience  stresses of looking for work, having to work in jobs which do not test their skills, or be involved in occupations  which require skills that are seemingly difficult to develop. Another common theme with adults that causes stress is having to work in a job which increasingly demands more of them, but does not remunerate them accordingly. In other words, they have to work more for less, and have to accept the gradual lowering of work conditions, but are unable to change jobs because they have already invested so much in it in terms of working years, but cannot leave and start afresh because the demands of a mortgage to pay off and a young family to provide for means they cannot start on a lower rung in a new occupation. Over a prolonged period, this can cause severe unhappiness.

Is it surprising that suicide affects men in their thirties and forties? This is a period for a man where work demands more, the mortgage needs paying, and the family demands more of his time and energy. It is unsurprising that having spent long periods in this sort of daily struggle, that men develop mental health problems which lead some to attempt suicide. But mental health does not just affect men. Among some of the this some women have to deal with are the struggles of bringing up children, the work life balance, the unfulfilled feel of not utilising their skills, and feeling isolated.

One of the ways ill health develops mentally is when people spend too long being pushed too hard for too long. Put under these kind of demands, the body shuts down as a self preservation measure. But the demands on the person don’t just go away. You may want a break from work. But this may not be possible or practical. In fact, the lack of an escape when you are aware you need one may be a greater trigger of mental illness, because it increases the feeling of being trapped.

It is little wonder that when people go through periods of mental ill health, an enforced period of short-term rest will allow them to reset their bearings to be able to continue at work, or return to work with some level of appropriate support. But this is only temporary.

With mental ill health problems, lifestyle adjustments need to be made for sufficient recovery.

Under the Equality Act (2010), your employer has a legal duty to make “reasonable adjustments” to your work.

Mental ill health sufferers could ask about working flexibly, job sharing, or a quiet room, a government report suggests.

The practicality of this however means more cost to the employer in having to make adjustments to accommodate the employee, and unless the employee is a valued one, whom the employer would like to keep, often the case is that they will be gradually phased out of the organisation.

In fact, when an employee attains a certain level of experience within an organisation, employers often ask more of them because they know these employees are locked in to their jobs, and have to accept these grudgingly, or risk losing their jobs, which they cannot do if they have dependents and financial commitments.
And you know the irony of it? The mental ill health sufferer already knows that. Which is why they don’t speak out for help in the first place.

If these employees complain, employers simply replace them with younger employees, who cost less, and who are willing to take on more responsibilities just to have a job. Any responsibilities the redundant employee had simply get divided up between his leftover colleagues, who are in turn asked to take on more responsibilities. They are next in line in the mental health illness queue.

And what if you are self employed? And have to work to support yourself and your dependents? The demands of the day to day are huge and don’t seem to go away.

You can see why mental health is  perceived a ticking time bomb. Organisations are not going to change to accommodate their employees because of cost, but keep pressing them to increase productivity without pay, knowing that they cannot say no, and when all the life and juice has been squeezed out of them, they can be chucked away and replaced with the next dispensable employee.

A ticking time bomb.

The financial considerations of investing in medicine and medical research

BBC News reports that a drug that would reduce the risk of HIV infection would result in cost savings of over £1bn over 80 years. Pre-exposure prophylaxis, or Prep, would reduce infection and hence lower the treatment costs for patients in the long term.

The catch? There is one. It’s the long term.

The cost of the treatment and prevention is such that its provision for the first twenty years – bundling together the cost of medical research and production of medicine – would result in a financial loss, and parity would only be achieved after a period of about thirty to forty years; this period is hard to define because it is dependent on what the drug would cost in the future.

Prep combines two anti-HIV drugs, emtricitabine and tenofovir. The medical trials behind it have concluded it has an effective rate of over one in five when it comes to protecting men who have unprotected sex with men from HIV infection. The exact figure is close to 86%.

Prep can be used either on a daily basis, or on what has been termed a sexual event basis – using it for two days before, during and after periods of unprotected sex.

The research model analysed the potential impact of Prep and found that it could reduce infection rates by over a quarter. The cost of the treatment itself, comparative to the cost of treating infection, would result in a saving over one billion pounds over eight years.

However, it does raise a few ethical questions. If the National Health Service is aiming to be a sustainable one – and one of the aims of sustainability is to empower citizens to take responsibility for their own health –  shouldn’t it be considering less about how it will balance the books, but spend more on education for prevention in the first place? The cost of producing Prep on the NHS would be £19.6 billion over 80 years; while the estimated savings from treatment would be £20.6 billion over the same period. Educating people not to have unprotected sex with those at the risk of HIV arguably would result in a higher saving over a lower time period. Perhaps the NHS should consider ways of reducing cost more significantly, rather than latching on to a cheaper prevention drug immediately. If consumer behaviour is not going to change, symptoms are still going to surface, and the provision of Prep on the NHS may only encourage less self-regulation and awareness.

Airbnb style recuperation for hospital patients

Would you welcome a stranger into your home? Would you have a spare room set aside for them? Perhaps not. But what if you were paid to do so? This is what some hospital bosses are considering to relieve overcrowding in hospital wards, that patients do their recuperating in private homes, rather than in the hospital. You offer a room if you have one available, and the hospital rents it from you for a patient. It is like an airbnb for hospitals.

On the face of it, this seems like a good idea. Hospital overcrowding is lessened, home owners get a bit of spare cash, the recuperating patient gets a bit of company … everyone’s happy. Patients staying out of hospitals mean that the backlog of operations can be cleared more quickly, resulting in a better streamlined NHS that benefits every citizen.

This idea is being piloted by the startup CareRooms. “Hosts”, who do not necessarily need to have previous experience in healthcare, could earn £50 a night and up to maximum of £1000 a month putting up local residents who are awaiting discharge from hospital. The pilot will start with 30 patients and the hope is that this will expand.

AgeUK claims that patients were being “marooned” in hospitals, taking up beds while 2.2 million days are lost annually to delayed transfers of care.

The specifics, however, do not seem to hold up to scrutiny. Who is responsible for the overall welfare of the patient? Once a patient is transferred to this “care” home, the responsibility of medical care is devolved to someone with basic first-aid training.

Prospective hosts are also required to heat up three microwave meals each day and supply drinks. Unfortunately it opens the issues of safeguarding, governance and possible financial and emotional abuse of people at their most vulnerable time.

The recuperating patients will “get access to a 24-hour call centre, tele-medical GP and promised GP consultation within four hours.”

The underlying question, though, is would you, though, want your loved ones to be put through this kind of care?

This is cost-cutting at its worst. The NHS is cutting costs, cutting ties and cutting responsibilities for those supposedly under its care. It would be a sad day if this kind of devolved responsibility plan became approved.

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.