CRN Review Highlights Need for New Criteria in Evidence-Based Nutrition

As clinical science proceeds on dietary nutrients and disease risk reduction, there remain serious limitations to even the hierarchy of acceptable clinical science on foods and dietary supplements.

In comparison to pharmaceutical drugs, foods and dietary supplements are faced with several unique obstacles in validating science on their perceived health benefits. A review of this wide issue has been published in the December issue of Natural Medicine Journal. It is authored by Andrew Shao, PhD, and Douglas MacKay, ND, senior vice president and vice president of scientific and regulatory affairs at the Council for Responsible Nutrition (Washington, DC).

The authors state that while drugs tend to have single, targeted effects on the body, nutrients tend to work in interconnected systems of various organs influenced by many nutrients. Drug trials work in a therapeutic context (treating, curing, or mitigating a disease already carried by subjects) while nutrient trials tend to focus more broadly on chronic disease risk reduction experienced over, in many cases, long periods of time.

Shao and MacKay highlight other obstacles to current nutrient trials, such as placebo patients taking their own supplements and vitamins, which can obscure trial results.

Funding proves to be another industry-specific concern. With intellectual property over a food or dietary supplement being difficult to defend, trials on these nutrients must often rely on academic or federal funding.

The need for a more expansive list of biomarkers remains a big issue in the United States and abroad. “The current accepted list [of biomarkers] is disappointingly brief and has changed little in the past decade,” state the authors.

Nutrient science continues to rely on its gold standard of the randomized, controlled trial (RTC), but Shao and MacKay stress that “…the RTC in its current form is ill-suited to assess the effects of nutrients on chronic disease risk and must be modified if it is to serve as an effective tool for evidence-based medicine.”

To read the full review at the Natural Medicine Journal, click here.