SCIENCE 101

Garlic, scientifically known as Allium sativa, is a complex mixture of chemicals displaying anti-viral, anti-bacterial, anti-cancer, anti-blood clotting, decongestive, cholesterol-reducing and immunity-boosting properties.

Garlic through history

Louis Pasteur noted in 1858 that bacteria died when they were doused with garlic. At the turn of the century, garlic was the drug of choice for tuberculosis. Albert Schweitzer used garlic to treat cholera and typhus. And during World War II, British physicians treated battle wounds with garlic. In Russia, it's called Russian penicillin.

Animal anecdote

French farmers sometimes feed garlic and onions to their horses to dissolve clots in the animals' legs.

There is little doubt that garlic reduces blood cholesterol. In studies of people with high cholesterol (over 200), one-half to one whole garlic clove daily typically lowered their levels by about 9 percent, according to a major review of the evidence by Stephen Warshafsky at New York Medical College in Valhalla. Benefits showed up in a month and also came from garlic supplements. Tufts University Diet and Nutrition Letter suggests two cloves of garlic a day might be as potent as some cholesterol-lowering drugs.

Artery Protector

A newly discovered garlic plus: It prevents bad-type LDL cholesterol from oxidizing, a process that initiates plaque buildup on artery walls, which can lead to clogging, heart attack and stroke. The theory is that unoxidized cholesterol is not very harmful. In a study by University of Kansas researchers, taking 600 milligrams of powdered garlic every day for two weeks reduced LDL oxidation by a remarkable 34 percent. So garlic eaters might have less harmful cholesterol than non-garlic eaters with identical cholesterol counts.

Blood Thinner

Studies suggest that garlic compounds help thin the blood, says Eric Block, professor of chemistry at the State University of New York at Albany. Block has isolated a garlic chemical, ajoene, (ajo is Spanish for garlic) with anti-coagulant activity equal or superior to that of aspirin. Raw garlic (three cloves a day) improved clot-dissolving activity by about 20 percent in a double-blind study of medical students in India. Cooking garlic might enhance its anti-clotting activity.

Cancer Blocker

Much research shows that garlic contains many chemicals that in laboratory animals block cancers of every type, including breast, liver and colon. A specific garlic compound suppressed the growth of prostate cancer cells in test tubes by about 25 percent, reports John Pinto of Memorial Sloan Kettering Cancer Center in New York. Dedicated garlic eaters may escape certain cancers. Example: In a recent study of 42,000 older women in Iowa, those who ate garlic more than once a week were half as likely to develop colon cancer as non-garlic eaters.

Infection Fighter

Garlic kills viruses responsible for colds and the flu, according to tests by James North, a microbiologist at Brigham Young University. Eat garlic when you feel a sore throat coming on, he says, and you may not even get sick. (Eat garlic when you're stuffed up, too: It acts as a decongestant.) Other studies suggest that garlic revs up immune functioning by stimulating infection-fighting T-cells.

I recommend eating one or two cloves of raw garlic a day to people with chronic or recurrent infections, says Andrew Weil of the University of Arizona College of Medicine, author of Natural Health, Natural Medicine. His tip: Cut raw cloves into small pieces and swallow them like pills.

Baby 'Appetizer'

Even babies like garlic. When nursing mothers eat garlic, infants stay longer at the breast and drink more, not less, milk, according to tests at Monnel Chemical Senses Center in Philadelphia.

To get the most benefit

-- At the Market

Buy unpackaged garlic, so you can feel the bulb. It should be solid, not light, airy or dried out. Press the cloves with your fingertips to be sure they're firm. Look for large-cloved bulbs in which the outer skin is tight, unbroken and free of soft spots.

-- In the Kitchen

Keep garlic in a cool, dry place. Store it in any container that allows good air circulation, such as special ceramic garlic jars with vent holes or any glass jar, small box, basket or similar container, loosely covered. Most experts do not advise refrigerating garlic. Peeled garlic cloves, tightly wrapped, can become moldy rather quickly in the refrigerator. Freezing, too, ruins uncooked garlic. Cloves that have sprouted are all right to use but may be milder in taste.

Caution: If you make dressings, oils, butters or marinades containing garlic, be sure to keep them refrigerated, and don't store them longer than two weeks. Otherwise, they pose a threat of potentially deadly botulism.

Raw or cooked?

-- For anti-bacterial or anti-viral effect, only raw garlic will do. Both raw and cooked garlic seem to have cardiovascular, decongestive and anti-cancer benefits.

-- Eating more than three raw cloves a day can cause gas, bloating, diarrhea and fever in some people. Cooked garlic is gentler on the stomach.

-- All garlic (crushed, chopped in jars, paste, even garlic powder off the spice shelf) can have health benefits.

Garlic Breath

Eating parsley or mints or sloshing mouthwash only temporarily dims garlic breath. Garlic infuses your blood and lungs, typically giving off an odor for 4-18 hours. The strength and duration of the odor depend on your body's individual reaction.

3 great garlic recipes

Company Garlic Chicken

2¹/2 pounds boneless, skinless chicken breasts, cut in serving-size pieces

1 Tb. canola oil

3 bulbs garlic, cloves separated

³/4 Tb. each fresh thyme and rosemary (or ¹/2 tsp. each if using dried herbs)

1¹/2 cups dry white wine, or enough to cover chicken in casserole

Salt and pepper to taste

¹/4 cup minced parsley

In a large skillet, fry chicken in oil over medium-high heat until golden brown. Salt and pepper chicken. Layer chicken in 4-quart casserole. Remove papery outer covering of garlic (do not peel). Put garlic on top of and among the chicken pieces. Sprinkle with thyme and rosemary. Add wine to cover. Bake, covered, at 350 degrees for 1 hour, or until liquid is reduced and garlic is very soft. Before serving, sprinkle with parsley. Serve with toasted Italian or French bread (squeeze soft garlic onto bread). Serves 6.

Per serving: 143 calories, 22.3g protein, 2.2g carbohydrates, 0.2g fiber, 2.4g fat (0.4g saturated), 153mg sodium

Garlic Bean Soup

2 cups vegetable or chicken broth

8 very large garlic cloves, peeled

1 medium onion, coarsely chopped

4 cups cooked white beans, or 2 19-ounce cans white kidney or cannellini beans, drained

Put the broth, garlic and onion in a large bowl; cover. Microwave for 20 minutes on high, or until vegetables are soft. Transfer to a blender or food processor, add half the beans and pure. Return soup to bowl, add remaining beans and microwave 5 minutes, or until beans are heated through. Serves 6.

Per serving: 195 calories, 13.9g protein, 33.9g carbohydrates, 8g fiber, 0.9g fat (0.25g saturated), 267mg sodium

Quick Guacamole

1 medium ripe avocado, mashed

1 tsp. lemon or lime juice

1 large garlic clove, crushed

4 drops hot sauce, such as Tabasco

¹/4 tsp. each salt and pepper

Mix all the ingredients. Serve with tortilla chips. Serves 2.

Per serving: 166 calories, 2.1g protein, 8.4g carbohydrates, 4.2g fiber, 15.4g fat (2.5g saturated), 277mg sodium

Jean Carper's current best-selling book is Stop Aging Now!

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