Having listened to part two of the Radio 4 show The Rise of the Lifestyle Nutritionists, I followed some links that had been posted on Ben Goldacre’s blog by Patrick Holford’s PR at 100% health and reached a page titled “Patrick’s full responses to Radio Four’s questions”.
The first clarification/response is on the Gladys Block paper. I seem to recall someone on the Radio 4 programme making the point that the people who were taking supplements may well have been taking other positive steps to improve health/maintain good health. I’d imagine it might be tricky to work out if there really were beneficial health effects from supplements if, say, the people who tended to take supplements also tended to: be in a different social class; and/or take more exercise; and/or eat a better diet. Rather than clarifying or defending his position, however, Mr Holford has simply linked to his original comments on the Block paper. No mention of the confounding factors that were referred to during the broadcast. How is that a ‘full response’ to Radio 4’s questions? Never mind ‘full’ – it’s not even a response.
Incidentally, the authors of that study made clear in their conclusion that their “study findings should also be weighed in the context of recent randomized controlled trials and related meta-analyses [39,40] which have raised concern about potential detrimental effects of select dietary supplements, particularly beta carotene and alpha tocopherol.” Ref 39 is to the Bjelakovic study. You know, the one that was a systematic review and meta-analysis of Randomised Controlled Trials. That’s right – it’s the one that Patrick Holford criticised for not using two observational studies.
***PDF of study: here.
****EDIT: Nearly forgot – there’s also a site called Holford Myths.