Q. A friend of mine sent me an article about garlic being toxic. He says it slows reflexes and impairs concentration. I am a great fan of garlic and use a lot of it when I cook. Now I am concerned about what my love of garlic may be doing to my health. Is this a real problem or an urban legend?
A. We think this is an urban legend. Garlic has been used in cooking and healing for thousands of years. If garlic were really hazardous, cooks around the world would be in big trouble, especially in southern Europe, China, India and Latin America.
Researchers have documented the cardiovascular benefits of garlic. It also seems to help control blood sugar and may reduce the risk of certain cancers.
High doses of garlic, either as a dietary supplement or in food, can irritate the digestive tract. Heartburn and nausea have been reported. Surgeons sometimes warn patients to avoid large amounts of garlic before an operation to reduce the risk of excessive bleeding.
One reader sent us his testimonial that eating garlic cured his ulcers. He hypothesizes that the garlic killed the Helicobacter bacteria in his stomach, and garlic extracts are capable of fighting this germ in the laboratory.