Truth is buried in latest antioxidant study attack

Antioxidants are being wrongfully accused, according to industry members who say the latest high-profile study slamming antioxidants contained conclusions that opposed those stated by the study authors.

The study, in which researchers concluded that antioxidants offered no benefits to women at high risk of cardiovascular disease, has been slammed outside the mainstream media because the study results were actually significantly positive when the researchers counted the subgroup of 68 per cent of study subjects who actually took the supplements.

"It?s like taking a room full of 100 hungry children, handing 50 of them a large sandwich, then declaring that sandwiches don?t work as food because half the room is still hungry," wrote nutrition blogger Mike Adams. "The results of the study can be made to look poor by counting the results of all the people who didn?t take the vitamins!"

The report, "A Randomized Factorial Trial of Vitamins C and E and Beta Carotene in the Secondary Prevention of Cardiovascular Events in Women" was recently published in the Journal of the American Medical Association?s Archives of Internal Medicine and concluded that: "There were no overall effects of ascorbic acid (vitamin C), vitamin E, or beta carotene on cardiovascular events among women at high risk for CVD… While additional research into combinations of agents, particularly for stroke, may be of interest, widespread use of these individual agents for cardiovascular protection does not appear warranted."

Neil Levin, clinical nutritionist and product formulator at Illinois-based supplements maker Now Foods, attacked the veracity of the findings. "This is simply untrue," he said. "In order to reach that conclusion the researchers had to count non-compliant subjects as taking vitamin E, even when it was obvious that they weren?t following the study protocol. Is that intellectually honest? I would have given the opposite conclusion."

When subjects assigned to take vitamin E actually took their vitamin E, the results were significant and proved that the vitamin had benefits, he noted. The research stated: "Censoring participants on noncompliance led to a significant 13 per cent reduction in the primary end point… Reductions in secondary study end points were also stronger, with a 22 per cent reduction in MI… a 27 per cent reduction in stroke… and a 9 per cent reduction in CVD mortality… There was a 23 per cent reduction in the combination of MI, stroke, or CVD death…Among those with prior CVD, the active vitamin E group experienced fewer major CVD events…"

Levin accused the researchers of "glossing over these admitted benefits." "This was wholly ignored in the study's conclusion, as well as the subsequent press release and extensive news coverage," he said.

Daniel Fabricant, PhD, vice president of scientific and regulatory affairs at the Washington DC-based Natural Products Association criticised the findings. "While study subjects had to be willing to forgo individual supplements of vitamins A, C, E, and beta carotene at levels beyond the US recommended daily allowance during the trial to control intake levels, the study makes a critical error in that there are no controls in place for dietary intake of vitamins C and E and beta-carotene through fruits and vegetables. We have no baseline of what the subjects' nutrient status was from food, thus to draw any comparison or conclusion doesn't really offer a complete view of the research picture."

He added: "Generally diet and exercise are very important components of secondary prevention, yet this study makes no mention of the exercise habits of the subjects, nor does it track some of the dietary habits like sodium (salt) intake, which are potential study confounders. The risk factors for eligibility in the study are rather broad and range from self-reported diagnosis of hypertension, high cholesterol level, or diabetes mellitus; parental history of premature myocardial infarction (MI) before age 60 years; obesity; current cigarette smoking; and inconsistent report of the subjects? prior medical CV. This variability of subjects has the potential to introduce bias and doesn?t reflect the scientific objective of secondary prevention."

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