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Wednesday, April 30, 2003No longer, the experts say, are they concerned about vitamin deficits. Those are almost unheard of today, even with the population eating less than ideal diets and skimping on fruits and vegetables. Instead, the concern is with the dangers of vitamin excess. "There has been a transition from focusing on minimum needs to the reality that today our problem is excess - excess calories and, yes, excesses of vitamins and minerals as well," said Dr. Benjamin Caballero, a member of the Food and Nutrition Board at the National Academy of Sciences and the director of the Center for Human Nutrition at Johns Hopkins University. This is nothing new. They’ve been teaching about vitamin toxicity in medical schools for years. The fat-soluble ones are particularly prone to having toxic effects, because they’re stored in the body fat for later use rather than excreted in the urine, like water soluble vitamins are. Their toxic effects are describe detail here: Vitamin A, Vitamin E, Vitamin D , and Vitamin K. Even Vitamin B6 can cause a toxic neurological disorder. Not only do large amounts of these vitamins cause toxic syndromes, they might actually make worse that which they’re promoted for improving: ...The most popular individual supplements are vitamins C and E, said Dr. Robert M. Russell, the director the Human Nutrition Research Center of Agriculture Department at Tufts University, who is head of the Food and Nutrition Board. Scientists once thought those vitamins could help prevent ailments like cancer and heart disease, but rigorous studies found no such effects. Vitamin E supplements can increase the risk of heart attacks and strokes, and studies of vitamin C supplements consistently failed to show that it had any beneficial effects... ...Several recent large studies indicate that people with high levels of vitamin A in their blood have a greater risk for osteoporosis. People can easily reach a potentially dangerous level, about five times the recommended dose, by taking vitamins and supplements, nutrition researchers say... ....Two large randomized trials of vitamin A and beta carotene that researchers hoped would show a protective value against cancer found no benefit, and one found that participants who took the supplements had more cancer. A large study of vitamin E and heart disease found that it did not prevent heart attacks and that people taking it had more strokes. Another study, of women with heart disease, found that antioxidant vitamins might actually increase the rate of atherosclerosis... ....a European study, reported recently at a meeting of the American College of Cardiology, found that folic acid supplements actually made matters worse for heart disease patients. The study, the Folate After Coronary Intervention Trial, involved 626 patients who were having stents inserted into blocked arteries to keep them open. Half were randomly assigned to take folic acid, and the rest took a placebo. Six months later, the arteries of those taking folic acid were significantly narrower than the arteries of those taking a placebo, exactly the opposite of what the investigators had expected. The article points out that other studies have shown the opposite effect. As one researcher puts it: "Over all, the likely explanation is that there is a neutral effect, and these relatively small trials found opposite findings due to the play of chance.” Exactly. posted by Sydney on 4/30/2003 08:14:00 AM 0 comments 0 Comments: |
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