Elevated LDL-cholesterol and low HDL-cholesterol levels in the blood are among the major risk factors for coronary heart disease (CHD), the nation’s No. 1 killer, and are subject to modification through diet, exercise, and if necessary, cholesterol-lowering medications. With average LDL-cholesterol levels above the desirable levels, it’s not surprising that adult Americans are seeking ways to lower their cholesterol levels.
Labeling laws allow foods or dietary supplements to make approved health claims relating their product to reduction of heart disease risk. Structure/function claims can identify relationships between nutrients or dietary ingredients and body function, but recent Food and Drug Administration courtesy letters indicate that manufacturers are not wording their structure/function claims properly.
The Nutrition Labeling and Education Act allowed two claims related to reduced risk of CHD: dietary saturated fat and cholesterol, and fiber-containing fruits, vegetables, and grains. CHD-related claims have since been approved for soluble fiber from whole oats and psyllium seed husk, soy protein, whole-grain foods, and, most recently, plant stanol/sterol esters. These (and all) health claims are held to the standard of “significant scientific agreement,” meaning that strong scientific evidence exists to support the relationship stated in the claim.
The Pearson decision forced FDA to consider the addition of qualifying statements to proposed health claims for dietary supplements that FDA felt did not meet the significant scientific agreement standard. FDA agreed to allow qualified health claims relating omega-3 fatty acids and certain B vitamins to heart disease, but not one for vitamin E supplements. It has been suggested that these claims be allowed on foods as well.
The structure/function claims of many dietary supplement products relate the use of the product to maintaining “healthy” cholesterol levels. The most controversial product of this type has been Cholestin, initially a supplement of red yeast rice extract, which contains lovastatin, the ingredient in the cholesterol-lowering drug Mevacor®. A U.S. District Court has upheld FDA’s position that red yeast rice products containing lovastatin are unapproved new drugs. Cholestin itself has been reformulated to contain policosanol, a compound that is described in clinical trials as a “cholesterol-lowering drug” that “inhibits cholesterol biosynthesis” but is described by its distributor as “an effective, natural way to achieve healthy cholesterol level.” Other supplements that contain red yeast rice extract are still on the market, and are receiving letters from FDA to indicate that these products are considered unapproved drugs.
Permitted structure/function claims “describe the role of a nutrient or dietary ingredient intended to affect the structure or function in humans or that characterize the documented mechanism by which a nutrient or dietary ingredient acts to maintain such structure or function, provided that such statements are not disease claims. . . .” FDA’s proposed rule on structure/function claims included as an example “helps maintain a healthy cholesterol level,” but the final rule narrowed the scope to those that explicitly indicate cholesterol levels already within the normal range. FDA has written that the claim “maintain healthy cholesterol levels . . .” or similar wording “suggests that the product is intended to treat, prevent, cure or mitigate disease, namely hypercholesterolemia.”
This narrowing of the scope of cholesterol claims has implications for a host of other structure/function claims, e.g., immune function (e.g., “promotes healthy immune system), urinary system (e.g., maintain normal urine flow), etc. FDA has already pounced on claims that state “maintain a healthy blood sugar level. . . .” It has been suggested that FDA may be employing a strategy to severely limit structure/function claims and encourage development of FDA-reviewed health claims.
The issue appears to be not semantics, but lack of standards. Health claims are held to the significant scientific agreement standard, but there is no comparable standard for structure/function claims. The Dietary Supplement Health and Education Act did not emphasize the quantity or quality of scientific evidence needed to substantiate structure/function claims, so there is tremendous variation in the evidence available for substantiation.
Although appropriate in FDA’s eyes, the suggested wording of cholesterol claims is not terribly useful. To the average American whose cholesterol is too high, the statement “already within the normal range . . .” suggests that the product is not appropriate for him or her, when in fact, it may do some good. Will this approach to structure/function claims make health claims on products containing plant stanol/sterol products or on fiber-containing fruits and vegetables look more attractive and stimulate consumers to seek cholesterol-lowering benefits from food rather than supplements? Probably not. What is needed is a consistent method for evaluating the substantiation for structure/function claims and an effective mechanism of educating the consumer about the meaning of various label statements and claims.
by R. ELAINE TURNER
Food Science and Human Nutrition Dept.
University of Florida, Gainesville