Vitamins and Health Foods: Where is the Real Evidence?

 

The article itself was short and was based on work that had been published in the Journal of the American Medical Association (dates, volume and pages NOT cited) and dealt with three supplements (Vitamins A, E and betacarotene the doses of which and durations used also NOT stated), all of which were associated with an increase in death rates in a group of 180,000 individuals who took supplements.

 

By itself, this type of information may sound alarming to the general public, but such alarms are what sell newspapers. The article went on to say that the researchers only were describing effects from “synthetic vitamins” and that their findings should not be translated to fruits and vegetables. Immediately after this statement (I had always been taught that fruits and vegetables contained vitamins) came disclaimers which tended to put the article in perspective. Ann Walker, of the Health
Supplements Information Service, stated, “The results of these mixed sample metaanalyses are worthless”, and Ellen Mason of the British Heart Foundation said, “There are good reasons to believe that antioxidant supplements protect against heart disease but a number of clinical trials have failed to provide
any robust evidence in favor of this.”

 

As if these two were not enough, the rest of the page contained comments by Dr. Thomas Stuttaford whose title was “Frenetic lifestyles mean we need to take multivitamins.” This was countered on the very same page by Nigel Hawkes’ commentary, which began
Phooey. A sensible balanced diet is the best investment.

 

Good readers, what is the average man or woman in the UK (or anywhere else, for that matter) to make of these totally contradictory statements on the same page in one of the worlds most widely read daily papers. Not much, to be exact, and the astute readers will go
directly to their physicians or various academic bodies for the real evidence.

 

Not unexpectedly it came and, by the very end of the same day, February 28, 2007 (sent from London at 10:50 PM GMT), the following email put out as a press release by the IASDA (International Alliance of Dietary Food Supplement Associations) was logged in on my computer
where it had been forwarded from one of my UK colleagues.

 

“The meta-analysis is not a study but a review of certain selected previous studies which combine a wide range of study populations, a range of different study designs and a number of different antioxidants with different mechanisms of action, given at different doses for different durations (28 days to 12 years), either alone or in combination.”

 

The conclusions go much further than the scope of the evidence and limitations of the individual studies used. Indeed, the papers results focus on all-cause mortality but the actual causes are not determined. The press release continued with comments by

Meir Stampfer, Professor of
Nutrition and Epidemiology at the Harvard

School of Public Health, who said the new analysis hasn’t discouraged him from taking his vitamins. Stampfer also said the studies were too diverse to pool together because they looked at various combinations and doses of antioxidants tested in different groups of
people. "This study does not advance our understanding, and could easily lead to misinterpretation of the data," said Stampfer, who was not connected to the new report. (This is what I tried to imply earlier but, then again, I am not a Professor of Nutrition and Epidemiology at Harvard.)

 

Complaints directed to the article in the Journal of the American Medical Association also were echoed by Andrew Shao, a scientist at the Council for Responsible Nutrition, a supplement trade association. He stated, "Only when they (the authors) included and excluded certain trials were they able to find this alleged increase in mortality, which they themselves can’t explain," Shao continued, "There is plenty of data out there that show regular use of antioxidant supplements help to maintain health."

 

As the title of this article implies, there is evidence and there is evidence. Sometimes it is clear; other times it is not. On still other occasions, the evidence is simply confusing.
Clearly, the article in the “London Times” is one of them. However, in balance I would agree with one of my esteemed British colleagues who recently wrote to the effect that there is no good evidence not to take nutritional (vitamin) supplements. What she did not emphasize at the time of her writing, however, is that most people do not eat healthy diets comprised of adequate amounts of fresh vegetables and fruits. In addition they eat foods that are loaded with fat and rarely drink milk in public, let alone school or home. The evidence for this last statement can be found at any food court in any shopping mall on either
side of the Atlantic Ocean at any time of the day or night.