More Bad News for Vitamin E, Beta-Carotene, and Vitamin A

From the March 2005 edition of Dr. Fuhrman's Healthy Times:

Studies indicate that more isn’t better...and may be worse!

Vitamin E was found not to prevent cancer or cardiovascular disease and can, in fact, increase the risk of heart failure. That’s the conclusion of an extended trial of thousands of older people with a history of cardiovascular disease or diabetes who were randomly assigned to take either 400 IU (international units) of vitamin E or a placebo.

The results, which were published in the March 16, 2005 issue of the Journal of the American Medical Association, found there was up to a 19 percent increase in the risk of heart failure in the study volunteers who took vitamin E compared to those on the placebo.

Earlier, a Johns Hopkins University study of vitamin E also suggested that a daily dose of 400 IU or more was linked to a 6 percent increased risk of death. In the analysis of 136,000 patients, the risk of death starts to increase at 150 IU, but at 400 IU, the risk of dying from any cause rises about 10 percent. This was another blow to the once-popular myth that taking extra doses of the antioxidant vitamins (E, C, and beta-carotene) helps protect against harmful free radicals and offers health-promoting effects, such as preventing heart disease.

Beta-carotene blues
Years ago, high doses of betacarotene were shown to increase the risk for cancer and death in smokers. In the last few months, beta-carotene has gotten more bad news. Six years after a study was halted early because a risky association between high-dose beta-carotene supplementation and heart disease and cancer was detected, follow-ups showed that for women, the bad effects lingered. The participants took 30 milligrams per day of beta-carotene plus extra vitamin A.

Researchers found that the increased risk of heart disease and cancer disappeared when the men in the study stopped taking the beta-carotene supplements, but the risk for women continued. Before the study was halted, the participants who took the supplement had a 28 percent greater incidence of lung cancer and 17 percent more deaths from all causes compared with those who didn’t take the beta-carotene. In the follow-up, women were 30 percent more likely to develop lung cancer, 40 percent more likely to die of heart disease, and 30 percent more likely to die of all other causes.

This lingering increased risk for women may be because beta-carotene and vitamin E are both fat-soluble, allowing any excess to accumulate in fat-cell membranes. This could explain the adverse effects of beta-carotene in women, who have more body fat than men. Vitamin C is water-soluble, and any excess leaves the body via urine.

Vitamin A problems

A recent study indicates that vitamin A intake dramatically weakens bones. A recent meta analysis of 20 studies indicated that vitamin A (retinol) intake—whether from diet (cod liver oil and animal livers) or from supplements—was negatively associated with bone density. As more vitamin A was consumed, hip fractures went up accordingly. The conclusion was that vitamin A supplements should not be used in any dose. Your body can make all the vitamin A it needs from the natural carotenoids found in fruits and vegetables.1
1. Crandall C. Vitamin A intake and osteoporosis: a clinical review. J Women’s Health 2004: Oct.13(8):939-53.
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Peter - February 24, 2012 1:21 AM

But then Stephen Byrnes said in his "Myths About Vegetarianism" article that the body inefficiently manufactures vitamin A from plant foods especially if you have type 2 diabetes?

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