Evaluating Claims of Sports Nutrition Supplements
Mike Sherman, Ph.D., Ohio State University Marjorie Hagerman, M.S., R.D., L.D., Ohio University

• FDA pre-market review is not required
• primary responsibility of the manufacturer is "safety" but clinical trials are not required
• Uniform labeling is required...
  • FDA regulates labeling information and accompanying literature
  • FTC regulates advertising
• Proff of efficacy is NOT required
• Three types of claims are allowed
  • nutrient content claims - this is basically a manufacturer processing claim that the product contains what it is supposed to contain
  • disease claims - i.e. calcium prevents osteoporosis
  • nutrition support claims - aka structure-function claims, i.e. calcium builds strong bodies
• FDA testing is NOT required

An ERGOGENIC supplement is any nutritional manipulation that improves performance...but, "enhancing performance relative to what?" is the main question.

Two types of effects are involved:

1. Acute - adaptation not affected
2. Chronic - adaptation affected
   • relates better toward enhanced performance claims

So who's telling the "truth"...the "truth" comes in many different forms:

• Personal Experiences - these are claims of regular people (i.e. non-professionals)
• Anecdotes of Coaches or Athletes or Others - these are claims from "industry" professionals
• Scientific Inquiry - the BOTTOM LINE

Scientific inquiry is performed by something known as the SCIENTIFIC METHOD. This method presumes the concept of CAUSALITY. That is that, every effect is assumed to be linked with a cause (cause and effect)...in other words, an experimental design attempts to determine a cause as influenced by an effect.

The ultimate purpose of the scientific method is to establish PRINCIPLES. A Principle is a rule or law concerning the functioning of natural phenomena. For example, "muscular training causes muscular adaptation". Therefore, a principle is certain or established beyond doubt or question...indisputable.

The problem here is that supplement research is tough to do due to:

• Poor funding
• Stubborn human subjects committees
• Recruitment of enough qualified subjects
• Motivation of subjects
• ability to control extraneous factors such as:
  • nutrition
  • sleep
  • interpersonal relations
  • other supplements
  • uncontrollable circumstances

So when you hear or read that a particular supplement does this or that, what types of scientific evidence would boost our confidence toward believing those claims:

• an appropriate subject population with random assignment to treatments. For example, you wouldn't use runners for a supplement marketed for cyclists
• appropriate control of pertinent factors
• double-blind, cross-over, placebo factors. Placebo must be exactly like treatment in terms of taste, color, temp, etc. Cross-over studies require a "wash-out" period to ensure the results of one treatment doesn't interfere with the next treatment.
• Familiarization trials - to eliminate variation in the rate of learning a task
• Measure variables to explain outcomes
• Appropriate statistical analyses

When evaluating an individual supplement whether for personal or team use, keep these things in mind:

Let's run through an example...using the supplement HMB