High Doses of Vitamin B-6 May Be Toxic, Scientist Warns

The high doses of Vitamin B-6 sometimes prescribed for premenstrual syndrome may be toxic, according to a University of Chicago scientist whose dietary guidelines mirror those recommended by other physicians debating the keys to women’s nutritional health.

Dr. Gary Shangold warned women against high doses of Vitamin B-6, which is commonly prescribed for premenstrual syndrome, a psychological and physiological disease characterized by depression, irritability, lethargy, joint and back aches and migraine headaches.

“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.

Can Cause Disorders

“Vitamin B-6 is proving to be toxic at lower levels than first thought,” he said. “Dosages of 500 milligrams per day or more can cause a variety or neurological disorders, including numbness in the feet, hips, hands and face.”

The recommended daily dietary allowance for Vitamin B-6 is two milligrams. But many premenstrual syndrome clinics and physicians prescribe between 800 to 2,000 milligrams per day, Shangold said, adding that recent studies show that 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, sharing the view of many physicians examining three common illnesses affecting women--cancer, osteoporosis and premenstrual syndrome.

C. Wayne Callaway, who chaired the convention, advised women to limit high-fat foods and increase those rich in calcium to battle the illnesses.

Value of Calcium

Dr. Bess Dawson-Hughes said that 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 of 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.

Since 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, Dawson-Hughes said.

Adult American women consume about 400 to 600 milligrams of calcium daily. “Therefore, they are getting only about 25% to 50% of the calcium believed necessary . . . , “ she said.

Diet Is Key

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 the total amount of fat in the diet, she said, indicating that a high-fat diet is associated with an increased risk for cancer, especially of the breast and the large bowel.

The panel of scientists recommended limiting the consumption of sweets, butter, salad dressings, soft drinks and alcohol and increasing milk and milk products, lean meats and raw vegetables.