Holford Watch: Patrick Holford, nutritionism and bad science

I was disappointed in the quality of evidence that Patrick Holford put forward to support his claims that we could learn, How to Eliminate Your Risk of Ever Having a Heart Attack. Since then, I’ve been reading through the intervention trials that have experimented with lowering homocysteine levels through supplementation etc. and whether they have succeeded in lowering those levels, but not the incidence of clinical disease. Ultimately, it is more relevant to consider whether you have decreased the incidence of disease or reduced its severity rather than concentrating on a particular measurement. When you alter a particular measurement such as a cholesterol or homocysteine level, but you don’t reduce the incidence of (say) heart attacks or strokes, then it raises the suspicion that you have identified a false surrogate endpoint.

So, I was more than a little interested when I came across Holford’s article, Homocysteine: Helpful or Hoax? I don’t fully agree with his conclusions but it is a shame that he doesn’t link to this less dogmatic article from the one where he claims that

Lowering your H score…dramatically reduces the risk of death from all causes, not just heart attacks.

Holford is aware of trials that don’t support his conclusions and discusses those results with particular reference to the objections made by Dr. Helga Refsum. This discussion does, of course, include the use of a rhetorical device:

So was this a cover-up of the sort all too common with inconvenient findings in drug trials?

Somewhere in there, the fine nuance of Refsum’s arguments is lost. Holford quotes Refsum:

If we are going to optimise treatment for heart disease patients we need to discover what works for them and what doesn’t…The problem is that the trials so far are too small to come forward with definite advice.

It could also be argued that the trials, so far, are insufficient to support Holford’s broad recommendation for testing and supplementation in asymptomatic individuals.

In the light of his recent objections and comments about folate fortification (here and here), it is worth mentioning that Holford quotes Refsum on this:

The business of folate fortification…may also be affecting the results. Since it was introduced, stroke rates in North America have dropped significantly - by 10% in the USA and by 15% in Canada. “Translated into British terms,” says Dr Refsum, “those figures suggest that adding folate to the diet could actually save more than 5000 lives a year.” [Emphasis added.]

There is considerably more to say on the matter but it may well be premature (at best) to recommend that large-scale homocysteine screening and ‘corrective’ supplementation would “eliminate your risk of ever having a heart attack”. The evidence isn’t satisfactory or sufficient for people who have already had heart attacks and it has certainly not been adequately established for people who are asymptomatic. Helpful or hoax - who knows? Overhyped on the basis of current evidence - that’s a different question.