The march of science carries on, and the results—as the industry well knows—are not always easy to agree with or swallow. So it was in a study of vitamins E and C and cardiovascular disease risk reduction in men released Nov. 12 in The Journal of the American Medical Association. Without mincing words, the authors wrote of the 8-year, 14,641-participant trial, "These data provide no support for the use of these supplements in the prevention of cardiovascular disease in middle-aged and older men."
Data for the study came from the Physicians' Health Study II, a randomized, double-blind, placebo-controlled trial of seemingly healthy male physicians 55 years and older. It assessed beta-carotene, vitamin E, vitamin C and multivitamin supplementation benefit on cancer, CVD and eye disease risk.
In a release, Daniel Fabricant, Ph.D., vice president of scientific and regulatory affairs for the Natural Products Association took issue with the study's lack of positive control, as well as difficulties with overlap of vitamin intake from food. Further, Fabricant questioned a vitamin C dosage disconnect between this and previous studies. "[The study] references nine pooled studies that when using 700 milligrams per day of vitamin C showed a 25 percent reduction in the occurrence of cardiovascular disease; yet this study only used 500 milligrams per day," he said. "Why wasn't the 700 milligrams per day amount used when that has been correlated with a reduction in occurrence in prior studies?"
According to Andrew Shao, Ph.D., the Council for Responsible Nutrition's vice president of scientific and regulatory affairs, the results aren't necessarily surprising. "We've seen this kind of thing with studies before," he said. "We see a hint of a benefit and we say 'Let's go for the [scientific] homerun.' But we might be overlooking some of the intermediate questions that can be just as important."
As an example Shao cites the Women's Antioxidant and Folic Acid Cardiovascular Study, which found no overall benefit for vitamins C, E, B6, B12, folic acid or beta-carotene for cholesterol and CVD reduction. It did, however, find that those women with prior CVD who supplemented with vitamin E had a "significant reduction in cardiovascular events."
"Hindsight is 20-20, but is it appropriate to study nutrients in isolation and expect a substantial effect?" he asked. "We need to refine our expectations for these nutrients as researchers, practitioners and consumers," he said.
Shao said the takeaway from the study shouldn't be that these aren't worthy vitamins, and he notes that this was a healthy study population and that there is yet more data to come from the trial. "Also, this one study doesn't erase all the previous studies," he added. "We really hope this study encourages more research to answer some of the questions it raised."