The Nobel Laureate, Werner Heisenberg, said “Since the measuring device has been constructed by the observer… we have to remember that what we observe is not nature in itself, but nature exposed to our method of questioning.” Perhaps in no other field has the method of questioning produced such disparate views as it has in nutrition. For example, observational studies of dietary habits have produced views of nature that are often diametrically different from views obtained via randomized controlled trials. Plausible hypotheses can be constructed to account for some of the differences, but others are not easily rectified. In addition, there is the fundamental problem that bedevils confidence in nutrition evidence at every level. Thus, while nutrition is the science of food, we have only rudimentary knowledge of the full bioactive constituents of foods. Moreover, our ability to measure, with any real degree of accuracy and precision, what people actually eat in the free-living condition is limited at best. What, then, can we say about providing Evidence-based Nutrition - and at what level of evidence? The conditions of “proof” are the same among all the “hard sciences,” conditions long agreed to as the “Scientific Method.” Should nutrition be excepted because satisfying the conditions in practice is difficult or impossible? Or should we just admit that our final answer is “maybe”?

Objectives:

Explore the notion of Evidence-based Nutrition and the validity/tools used to determine “proof”
Examine the diametrically differing views of observational study and controlled trials

Dennis M. Bier MD

Children's Nutrition Research Center; Baylor College of Medicine, Houston, TX

Appearances