Monday, January 07, 2008

Selective facts produce poor journalism (or science).

Selective facts produce poor journalism (or science). For example, the Women's Health Study had a 7% reduction in major cardiovascular events with vitamin E, a number that was not significant. But there was a significant 24% reduction in cardiovascular death in the vitamin E group. Would you characterize that as a failure for vitamin E? The media did. Yet, the authors of the study admitted that, "This was largely attributable to fewer sudden deaths in the vitamin E group (38 vs 51 among women assigned to placebo) and fewer deaths from other cardiovascular disease (ie, deaths due to cardiovascular diseases other than ischemic heart disease and cerebrovascular disease, 20 vs 34, respectively)." The Williams College ginkgo study in JAMA allowed participants to miss up to 6 daily doses over a 2-week period (nearly 50%!) before they were eliminated for non-compliance. It also tested only one brand of ginkgo (Ginkoba) on healthy volunteers for only six weeks, with results (by convention) not applicable to other brands. This was an obvious attempt to see whether a quick, drug-like effect could be obtained from a short course of supplementation. Longer term studies are more authoritative, especially if compliance is better. The CoQ10 statement is laughably wrong: "Coenzyme Q10 has not been carefully tested to see if it is safe and effective. Because coenzyme Q10 is sold as a dietary supplement rather than a drug, it is not regulated by the US Food and Drug Administration." This is a complaint that the FDA does not test individual dietary supplement products for potency or approve individual label claims. The agency does have the longstanding right to veto dietary supplement label claims and to remove any mislabeled or adulterated product from the national market. This contrasts with the FDA's explicit approval of drugs and drug claims, though the agency doesn't test individual pharmaceuticals for potency or safety, either. Of course, the FDA would take issue with their supposed inability to regulate dietary supplements. They even claim the opposite on their web page. Note the first 4 words: "FDA regulates dietary supplements under a different set of regulations than those covering "conventional" foods and drug products (prescription and Over-the-Counter). Under the Dietary Supplement Health and Education Act of 1994 (DSHEA), the dietary supplement manufacturer is responsible for ensuring that a dietary supplement is safe before it is marketed. FDA is responsible for taking action against any unsafe dietary supplement product after it reaches the market. Generally, manufacturers do not need to register their products with FDA nor get FDA approval before producing or selling dietary supplements.* Manufacturers must make sure that product label information is truthful and not misleading. FDA's post-marketing responsibilities include monitoring safety, e.g. voluntary dietary supplement adverse event reporting, and product information, such as labeling, claims, package inserts, and accompanying literature. The Federal Trade Commission regulates dietary supplement advertising." regarding the CNN report:

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