By Jerome Burne
A fine example of post truth and alternative facts appeared in the Guardian on Monday. Defining any diet that made a medical claim as a fad, the article consigned them all to the bin. See more The author writes cook books on baking packed with recipes for different ways to combine sugar, trans fats and refined flour. Perhaps health is not a priority.
But it was a powerful demonstration of the degree of confusion around diets. So how did we get into this mess? Common suggestions include mixing up being slim and stylish with health or concentrating on weight loss to the exclusion of everything else, ideas which then get amplified in the echo chamber of social media.
But I think there is a more fundamental reason. It’s the result of the system we use to tell us what treatments are effective and safe – Evidence Based Medicine (EBM). But it is not working well. It gives an easy ride to drugs – creating a lot of casualties in the process – but raises the bar impossibly high for diets and lifestyle approaches. Sorting it out would make such post-truthism just a bit harder.
The background to the Guardian article was a BBC Horizon program on the Clean Eating diet which advocates cooking from scratch, using real rather than processed food,which had been inspiring others to do the same. See more What’s not to like?
Fake Evidence Based Medicine
The charge, being investigated by biochemist Dr Giles Yeo, was that those involved in Clean Eating had become too involved with diets that lacked evidence. One recommends keeping your system on the alkaline side which means avoiding highly acidic foods such as grains. The other was going gluten free because of damage it can do to the guts.
The response from doctors, who rarely have nutritional training, is that if you are pushing a diet it should have an evidence base. ‘Why don’t they just put up or shut up?’ is the attitude.
The answer is that the EBM system that doctors rely on to sort good evidence from bad doesn’t actually do that. It is better described as a Fake Evidence Based Medicine (FEBM ) system and it has done wonders for the drug industry – massive rise in sales over the last decade – and for the big food companies. It also justifies the medical profession’s general refusal to take the link between food and health at all seriously –examples include hospital food and zero medical training for doctors. It is one of the reasons we are now in the grip of epidemic of chronic diseases rooted in diet and life style.
The Horizon program provided a handy primer for the principles authentic EBM should follow. They include: Scientists should be detached and impartial in investigating and reporting on what they find. At the same time they should remain curious and open to new findings.
Commercial Evidence Based Medicine
When a treatment is found not to work it should be abandoned. Scientists should be able to replicated trials, so the data they gather has to be freely available to other researchers.
My own view on EBM is similar to the line supposedly taken by Mahatma Gandhi when asked what he thought of Western Civilization. He said he thought it would be a very good idea.
Lifestyle treatments have a problem gathering evidence because they inevitably fail the ‘gold standard’ of EBM – the Randomised Controlled Trial (RCT) which compares two groups, one which gets the treatment and the other doesn’t. Actually to be more precise, they almost never take the test. Most non-drug treatments have promising results from animal work plus a few short, small studies involving 10 or 20 people.
Going for an RCT, however, is a big jump up. They involve hundreds of people, take years and cost millions. Diets and the like rarely earn the sums needed because unlike drugs they don’t have a patent that gives them exclusive marketing rights. So what we have is not EBM but what might also be called Commercially Based Medicine (CBM). Most RCTs are paid for by drug companies which are not interested in testing cheap, possibly effective but unpatentable treatments.
Good for TV but not sensible
Ignoring this distinction allows TV presenters like Yeo to turn to the camera and say triumphantly something like: ‘So that’s why I prefer to rely on treatments that have been proved by science.’ CBM makes for good TV but is not a sensible way of answering important questions about how different diets affect our health.
Another failing of FEBM/CBM is that when it does test profitable drugs. the results don’t square with the fine EBM principles. The cholesterol lowering drug Ezetimibe, for example, was run through many RCTs to find if it cut the risk of cardiovascular disease. Not one showed clinical benefit. Instead of withdrawing it, however, the NHS spent 70 million a year on it.
Making data collected in trials available to other researchers has been totally ignored as far as statins are concerned. None has seen the raw material that provides the evidence for giving statins to 12 million people in the UK alone. Imagine Dr Yeo’s outrage at if the evidence for a vitamin or diet was obtained in the same way.
But even if FEBM keeps diet and non-drug treatments apparently evidence free, you might expect the British Dietetic Association to be an organised and vociferous lobby for a clear policy on diets. Instead the profession has painted itself into a corner by its close connections with the food industry, making another link to CBM.
Testing for 40 years and still no result
It is no accident that the low fat and high carbohydrate diet that dietitians have advocated for 40 years – one of the oddest fad diets of all – is very agreeable to the food industry.
Dietitians are now locked in a war over evidence with an impressive group of researchers, journalists and clinicians making a strong case for the benefits of a low carb diet, especially for diabetes.See more Dietitians deny this and say the RCT evidence for the low fat diet is strong. The fact that the diet has had more RCTs than any other diet and that after 40 years the situation is still unclear is further evidence that EBM is failing badly
As if this wasn’t enough the rules of EBM mean that the patient’s voice is effectively excluded from discussion and debate.
If you have been prescribed drugs your only responsibility is to take them – their benefit is after all evidence based.
If you suffer side affects you may be told that you just need a stronger dose or that you are imagining them. Medical interest in investigating the extensive reports of side effects from statins or the addictive properties antidepressants, is minimal. A patient’s experience is, as far as EBM is concerned, is just an anecdote; without another RCT it doesn’t count for anything.
Why is FEBM like neoliberal economics?
Should you take part in a drug trial, with the risk of suffering serious side effects or getting no treatment at all, you will still have no right to the information you made it possible to gather.
And your oncologist, should you be unlucky enough to have one, will be very unlikely to be remotely interested in a claim that changing your diet has really helped.
All of which makes me think of the failure of another ideology – neo-liberal economics. It also promised much, relied on experts who supposedly understood its statistical complexities and failed to hear the complaints of those for whom the system wasn’t working until it was too late.
Patient involvement is key to a more responsive form of EBM. Already there are signs that change is coming. A few GP’s are ignoring guidelines and offering a low carb diet for diabetes. Patients are increasingly ready to try various diets and see what works best for them. Most interesting is the move to transform ignored anecdotes into big data. Tens of thousands of diabetics have been uploading reports of the benefits of the low carb diet onto the patients’ website diabetes.co.uk. See more
Maybe soon the claim that what we eat has no effect on our metabolism and health won’t even be acceptable on an alternative fact list.