Megadoses Of Vitamin B-6 May Be Toxic
SAN FRANCISCO (AP) _ High doses of vitamin B-6, often prescribed to combat premenstrual syndrome, may be toxic, according to a scientist who recommends women get the vitamins they need through diet.
Dr. Gary Shangold of the University of Chicago discourages high doses of vitamin B-6, which is commonly prescribed for PMS, a disorder chararcterized by pre-menstrual depression, irritability, lethargy, joint and back aches, headaches and other problems.
″The idea that megadoses of water soluble vitamins, including all B vitamins as well as vitamin C, are safe because they are excreted in the urine is simply not true,″ Shangold said Monday during a convention of the California Dietetic Association and the Dairy Council of California.
″Dosages of 500 milligrams (of vitatmin B-6) per day or more can cause a variety of neurological disorders, including numbness in the feet, hips, hands and face,″ he said.
The recommended dietary allowance for vitamin B-6 is two milligrams. But many premenstrual syndrome clinics and physicians prescribe between 800 and 2,000 milligrams per day, said Shangold, adding that recent studies show vitamin B-6 may be toxic at levels as low as 250 milligrams per day.
″It may be better to eat complex carbohydrates, including breads, cereals and dried peas, beans and lentils,″ he said.
Others at the convention also recommended dietary adjustments to help prevent cancer and osteoporosis.
Dr. Bess Dawson-Hughes said if women in their 20s, 30s and 40s consumed 1,000 milligrams of calcium a day, the incidence of osteoporosis would be dramatically reduced.
Osteoporosis is a painful disease that causes spontaneous fractures in the spine, hips and wrists. One in four American women over the age of 60 suffers from the disease, which is responsible annually for more than 1 million broken bones and $3.8 billion in related medical costs.
Because the long-term effects of high-dosage calcium supplements are unknown, women should increase their intake of calcium from food and use calcium pills only as a secondary source, Ms. Dawson-Hughes said.
Adult American women consume about 400 to 600 milligrams of calcium daily, ″only about 25 to 50 percent of the calcium believed necessary,″ she said.
Diet also is a key to reducing the risks of cancer, said Sushma Palmer, executive director of the Food and Nutrition Board of the National Academy of Sciences.
Women can reduce the risk of cancer by cutting back on fat, she said.