Mort Satin sent in this blog:

"Vitamins No Magic Bullet for Heart Health," "Study doubts antioxidant benefits for heart risk women," "Vitamins May Be No Match For Mother Nature," typical headlines resulting from a just published study in the Archives of Internal Medicine. I find it odd that there is such an uproar over the finding that individual nutritional elements, such as vitamins C and E or the antioxidant beta carotene in pill form do not contribute to health in the same way as when they are consumed as integral components of fruits and vegetables.

This study highlights a number of fundamental problems we encounter in modern nutrition-based medical research. We have come to rely very heavily on epidemiological studies, regarding them as functional rather than numerical relationships. Theories, policies and interventions are churned out of the health establishment based upon the tyranny of statistics rather than a knowledge of the underlying physiological mechanisms. That's how we end up with the swarm of "paradoxes," the French paradox, the Italian paradox, etc. Is it the wine, or perhaps the omega 3, 6, and 9 fatty acids? Should we focus on flax or concern ourselves with nutrient flux? Most importantly, can we isolate the one magic bullet that will rationalize the statistics we observed? With that one magic bullet, it would be child's play to promulgate a health policy and a simple intervention strategy. Unfortunately, life processes seldom revolve around single bullets.

Another primary problem is the lack of knowledge concerning the contradictions we observe between laboratory studies and clinical trials. As an example, most people believe that the majority of vitamin C is lost during processing because laboratory analysis indicates the ascorbic acid is gone. What has actually happened is that the ascorbic acid is converted into dehydroascorbic acid, which doesn't show up on the standard laboratory analysis. However, dehydroascorbic acid has virtually the same health benefits as ascorbic acid. The laboratory analysis says the vitamin C is gone, it has ceased to be, it is no more, however, our astute bodies tell us it's not - another example of the "in vitro, in vivo paradox."

The same paradox is evident in the countless dietary studies carried out, sponsored by the National Institutes of Health. Many of these studies begin with the notoriously inaccurate, self-professed food survey - the 24-hour recall ("I don't remember eating that Twinkie," said the adiposed adolescent). Once this questionable set of data on intakes is collected, it is usually put through clever computer programs such as the Minnesota Nutrition Data System software which converts these stated intakes into nutrients, based upon the ubiquitous, but inadequate USDA tables and other data on proprietary food preparations. The USDA tables disregard the issue of digestibility (or more correctly, indigestibility). These tables and the numerous computerized nutrient data programs that derive from them, assume that everything is fully digested - 100% bioavailability. This is, of course, wrong. The most digestible protein, egg albumin is only about 95% digestible, while celery can be down to 65-70% on a dry matter basis. This means that a significant portion of micronutrients may not be available.

We brush aside the impact of indigestibility of individual foods as well as the impacts of one food upon another. This is strange since we have long accepted the positive, synergistic effects of foods taken together, such as bread and milk, where the essential amino acids complement one another. Why deny the flip side of indigestibility? If you eat your eggs together with a few florets of broccoli, how much of the egg nutrients do you actually digest? Without knowing with precision which nutrients are absorbed in what amounts, data is churned out, often to several decimal places, for us to ruminate and develop theories upon. Garbage in, garbage out. On top of that, a lack of appreciation of the impact of micronutrients generated by gut microorganisms confounds our conclusions even further. So we end up observing what was taken in and observing the final outcome, but not knowing much about what actually happened in the process. Not a very sound basis upon which to promulgate health policies and interventions. It highlights the disconnect between what is observed in the laboratory (i.e. the USDA tables) and what actually happens in real life.

This unfortunate combination of poorly executed analysis, imprecise knowledge of physiological mechanisms and the unremitting drive to find a singular explanation to statistical relationships results in policies, advice and interventions that do not stand the test of time. We have seen this with hormone replacement therapy, salt reduction programs and we see it again with prescribed vitamin regimes. No wonder we see headlines such as, "Vitamins May Be No Match For Mother Nature."