Drinking too much causes heart disease, but drinking red wine reduces the risk. Eating red meat increases your risk of certain types of cancer, but protects your heart. We see a new headline every week telling us not to eat what we were eating last week, or to start eating what we stopped. Just look at the reversal of fortunes the humble packet of butter is having!
In this world of evidence-based medicine, where science is supposed to cure or even eradicate every disease, how can it all be so confusing? How do you know which headlines deserve your attention, and which ones will be tomorrow’s chip paper?
A colleague of mine, who holds a PhD in Exercise Physiology and is a member of the Royal Statistical Society, recently explained to me how such confusion exists. In years gone by, scientists and researchers devoted their whole careers to the study of one subject, often a very specific subject. Part of their job was to continually publish research that supported their theories.
If enough evidence existed that the theory was correct, then those theories would be accepted as laws of science. Think of the laws of motion, gravity and thermodynamics as examples. If a theory was disproved, a life’s work could almost be thrown out and those new findings had to be explored. If a finding couldn’t be replicated, it was considered to be a fluke and of little value. Many of these early scientists were either independently wealthy, or their work was funded by wealthy benefactors, and thus were under little pressure to produce results for anything other than the greater good of the community.
In more recent times, science – especially from a medical perspective – has become ‘evidence based’, where the quality of evidence is considered to be dependent on the research design, the removal of confounding variables and the power of statistics. Funding for scientific work is now more likely to come from either government grants or companies with an interest in the field.
Publication in a journal attracts attention, and thereby funding, and the more money you get in the form of grants, the more pressure there is to publish your findings. Added to this the number of scientific publications has increased significantly in recent years, all competing for market share like any other newspaper or magazine. And much like newspapers and magazines on the shelf, a good headline will attract more attention, and nobody wants to be repeating old news.
Thus we have arrived in an age where researchers are under constant pressure to publish something, journals need to publish something new as often as possible and positive findings are more likely to be published than negative. Recently a group of researchers replicated 100 studies with positive findings from the top journals in the field of psychology and found that only 36 percent of them could be reproduced – 64 percent were flukes.
Where does this leave the non-scientifically minded when they read the health section of the newspaper each week? Confused. Heck, without reading the full study, or sending it on to my aforementioned statistician friend, I’m never too sure what to think. But there are a few filters that he applies that work very well for me.
Firstly, does it stand up to the laws of physics and chemistry? Because if it doesn’t, it’s rubbish. Secondly, does it work from an evolutionary perspective? Did we evolve sitting in dark rooms, eating processed food? As Theodosius Dobzhansky said in 1973 ‘nothing in biology makes sense except in the light of evolution’.
And lastly, the findings need to be looked at in context. Is it relevant and how relevant? For instance in a recent report that received significant coverage linking red meat to cancer, it was suggested 34,000 people worldwide die due to meat-related colorectal cancer each year. When you consider more than a million die due to smoking, and almost half a million from malaria, the risk is pretty low.
My suggestion is simply to take everything in moderation and use a bit of common sense. The odd steak is good for you; a packet of frozen burgers every night, not so much. Six pints a day mightn’t be very clever, but that glass of red wine sitting on my kitchen bench right now – it’s medicinal!
> Andrew O’Brien is a chartered physiotherapist and the owner of Wannarun Physiotherapy and Running Clinic at Westport Leisure Park. He can be contacted on 083 1593200 or at www.wannarun.ie.