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Vitamins may have interaction with your medication

Does your doctor know you are taking vitamins? Millions of Americans are swallowing supplements in secret. They are afraid physicians might ridicule them for wasting their money.

Although many doctors think that supplements are silly, physicians may not be as knowledgeable about nutrition as they should be.

Twenty years ago, one of the world's foremost nutrition experts, Dr. Jean Mayer, wrote, "Our studies at Harvard suggest that the average physician knows a little more about nutrition than the average secretary _ unless the secretary has a weight problem. Then she probably knows more than the physician."

A new survey of family medicine residents shows that medical education is still inadequate when it comes to drug and nutrient interactions. This can have serious consequences for patients' health.

Cornell University researchers questioned 834 medical residents and found 83 percent had little or no training on this topic in medical school. On a test of this material, these physicians got 39 percent of their answers wrong.

Part of the problem is that nutrition education sometimes seems boring. "Eat your vegetables" can't compete with the thrill of laparoscopic surgery. But some medicines interact dangerously with supplements.

Popular blood pressure medicines like Capoten or Vasotec may become hazardous if a person is taking potassium supplements or using a potassium-based salt substitute. Such combinations could result in a buildup of potassium that could trigger irregular heartbeats.

Some medications deplete the body of crucial nutrients. Folic acid is considered very important for good health. Not only does it help prevent certain birth defects, it may also protect the heart and reduce the risk of certain cancers.

Aspirin for arthritis, blood pressure medications containing triamterene (Dyazide, Maxzide) and estrogen hormones (found in birth control pills and postmenopausal replacement therapy) may all reduce folic acid levels.

Multiple vitamin tablets often contain minerals as well. This could be detrimental if a person were taking Synthroid to correct a thyroid imbalance or Cipro or Floxin to treat an infection.

The minerals could interfere with the medicine and make it less effective.

A patient taking tetracycline to treat Rocky Mountain Spotted Fever or a pelvic infection like chlamydia could suffer grave consequences if she also took calcium or iron at the same time.

Finding information on drug and nutrient interactions is not easy. Medical reference books often overlook this topic or bury the nuggets where they are easily ignored.

If you would like to protect yourself, you can order our guide to Drug and Nutrient Interactions. Please send $2 with a long (No. 10) stamped, self-addressed envelope to Graedons' People's Pharmacy, No. N-22, P.O. Box 52027, Durham, NC 27717-2027.

Make sure your doctor knows what vitamins and minerals you are taking. Then ask if there could be any serious interactions with your medicine.



Question: When is the best time to take calcium, with meals or on an empty stomach?

Answer: For most people it may not matter. Older people, however, may have lower levels of stomach acid, making calcium absorption more difficult. They should take calcium supplements with meals.

Joe Graedon is a pharmacologist. Teresa Graedon is a medical anthropologist and a nutrition