Vitamin ReportBy Caty Weaver
This is Bill White with the VOA Special English SCIENCE REPORT.
Vitamins are necessary for good health. They are found naturally in foods. Drug companies also produce vitamins in pill form.
Vitamins C and E are called antioxidants. They are believed to fight destructive molecules in the body called free radicals. Free radicals are made of oxygen and nitrogen. They can damage cells. Free radicals have been linked to many diseases including cancer, eye disease, heart disease and strokes.
American medical experts examined studies on the effectiveness of vitamins in fighting disease. The Institute of Medicine of the National Academy of Sciences issued a report. It says there is no clear evidence that huge amounts of antioxidants prevent disease. And the experts say extremely large amounts of some vitamins may cause health problems.
For the first time, the Institute of Medicine is advising Americans to limit their use of vitamins. The report says most Americans can get all the vitamins they need in the foods they eat. The report says people should eat foods rich in vitamin C every day. Vitamin C is found in oranges, potatoes, strawberries, broccoli and leafy, green vegetables. The experts say people who smoke tobacco products should eat even more foods with vitamin C. This is because smoking can remove some vitamin C from the body. However, the experts say people should not have more than two-thousand milligrams of vitamin C in foods and pills each day. Too much vitamin C can cause diarrhea.
The Institute of Medicine says people should eat foods containing vitamin E each day. Sources include vegetable oils, nuts, seeds and leafy, green vegetables. But the experts say too much vitamin E in pill form can increase the chances of bleeding inside the body. They say people should take no more than one-thousand milligrams of vitamin E in pill form each day.
The report also discussed use of the antioxidant mineral selenium. It is found in seafood, meat and grains. The scientists say people should eat foods that contain selenium every day. But, the report warns that too much selenium can lead to hair loss and nail damage. The experts say people should not have more than four-hundred micrograms of selenium a day.
This VOA Special English SCIENCE REPORT was written by Caty Weaver. This is Bill White.