Sensible, well-written analysis of dietary supplements - pinch me!

A quick post to flag a really rather level-headed article in today's Guardian about antioxidants and dietary pills - one that looks at why taking such pills seemed plausible in the first place and at the mounting evidence that supplements laden with antioxidants may not only be ineffective at protecting against disease but may actually cause harm.

The author describes how the initial observation that reactive oxygen species (ROS, or free radicals that are formed as a by-product of most cellular activity and can damage proteins and DNA) play a role in many disease processes lead to the use of antioxidants (anything that mops up free radicals) as dietary supplements. The interesting point for me is that the article, written by a Justine Davies, has a very clear chronology not usually seen in pieces like this (honourable exceptions such as those from Dr. Ben Goldacre aside...). The grounds for belief X (i.e. that because free radicals have a role in disease, and because antioxindants mop them up, and because those with diets rich in antioxidant-rich fruit & veg live longer and healthier) are first set up almost dispassionately - reading about this you get the impression that up to this point scientists had got it pretty much spot on, which of course they had. Then the way in which industry latched onto belief X and created range of products Y, which were touted as powerful protectants against ageing/cancer/heart disease/itch eyes. Finally, the evidence that Y can actually do the opposite of what's intended is dealt with well.

Davies explains how the diet pill industry really got excited about antioxidants - all you have to do is visit holfordwatch.info to see just how excited - to the extent that tens of millions now take dietary supplements containing antioxidant vitamins. Only the science didn't stop there, and neither does the article. The key is that instead of credulously buying into the attractive mantra that antioxidants would help avoid cancer/heart disease/everything under the sun, Davies examines new evidence from large RCTs and meta-analyses that either show just how ineffective these supplements are, or indeed how damaging they can be.

The details are in the article itself, go and read it - my point here is that the way it's written reallty ought to form a model for science reporting. Careful analysis of evidence regardless of how difficult it may be to stomach (the supplement pill industry is worth billions), easy-to read explanations of the science involved, clear conclusions that align with current scientific consensus. Well done, now let's have more like this...!