With asthma, the name of the game is prevention. Although asthma sufferers are usually well-versed in basic prevention measures -- such as reducing exposure to dust or cigarette smoke -- few consider the importance of nutrition.

Certain foods are linked to asthma flare-ups. One of the biggest culprits is the food additive MSG and chemicals called metabisulfites, which are often used as salad preservatives. Metabisulfites are also found in some canned foods, beverages and processed foods, such as potato chips. In some asthma sufferers, food dyes can also cause an attack. And some researchers believe that asthmatics fare better by largely avoiding meat and dairy products. Dairy products can produce secretions that exacerbate asthma, says Peter Katona, MD, of the University of California, Los Angeles.

While some foods seem to aggravate asthma, others might help sufferers live with it. Dr. Gerald M. Lemole, a Delaware physician and researcher, is among a growing number of experts who believe that nutrition plays a significant role in almost every disease and ailment. In his new book, "The Healing Diet" (William Morrow, 2000), Lemole urges asthmatics to try a diet abundant in onion, garlic and spicy foods, which seem to act as natural bronchodilators. In addition, large amounts of fruits and vegetables in the diet might be helpful because of their high vitamin content. One study has even shown that vitamin C works as an antihistamine to reduce asthma attacks.