Antioxidant substances combat free radicals linked to cancer, early aging and other ills. Black and green tea are equal in antioxidants. Both varieties come from a warm-weather evergreen, Camellia sinensis. For green tea, leaves are chopped, rolled, steamed or heated, then dried. For black tea, leaves are crushed and exposed to air to change chemical composition, color, taste.

Folk fact

Tea was discovered in 2737 B.C. by Chinese Emperor Shen-Nung when tea leaves blew into boiling water.

TEA's BAG

-- Researchers at the National Institute of Nutrition in Rome, who had subjects drink a cup of black or green tea brewed for two minutes, said antioxidant activity in the blood rose 41-48 percent in 30-50 minutes, returning to normal after 80 minutes.

-- Tea blocks a broad spectrum of cancers in lab animals, according to researchers at Rutgers University. And it works in ordinary amounts consumed by tea drinkers.

-- Dutch men who had diets high in antioxidants called flavonoids, mainly from drinking a couple of cups of black tea daily, had just one-third the rate of fatal heart disease of those who drank less tea.

-- A study by the National Cancer Institute in China found that esophageal cancer dropped 20 percent in men, 50 percent in women, who had at least one cup of green tea daily.

-- Tea has antibacterial powers that help prevent cavities and gum disease, several U.S. and Japanese studies have shown.

TEA COUNTS AS A VEGETABLE

Prominent cancer researcher John Weisburger, director emeritus of the American Health Foundation, drinks about five cups of tea a day. He says they deliver as much antioxidant punch as two fruits or vegetables.

Drinking Tips

Hot or iced, try tea with meals. Weisburger says tea's chemicals may help counteract carcinogens in food, notably in grilled, fried and broiled meat.

At The Store

Find green tea at Asian markets, health-food stores, Japanese restaurants and some supermarkets. Lipton and Bigelow, for instance, sell green tea. Beware bottled teas: Some have up to 15 teaspoons of sugar.

The upside of caffeine

Undeniably, caffeine can make you think faster, perform certain mental tasks better and stay alert. Roland Griffiths, a Johns Hopkins University neuroscience and psychiatry professor, says caffeine produces elevations of feelings and well-being, sometimes even euphoria. Tests by the Massachusetts Institute of Technology show it takes only one cup of coffee in the morning and another at mid-afternoon to jump-start the brain and sustain a mild high. (Coffee has three times the caffeine of tea.) More caffeine doesn't boost performance.

-- Also: Caffeine opens the bronchial passages. Coffee drinkers experience less wheezing and asthma, research indicates.

The downside? It depends

Sensitivity varies. One person might be addicted to the caffeine in a single daily cup of coffee; another person might require five to 25 cups to get hooked, Griffiths reports. Caffeine can induce headaches, insomnia and anxiety. Coffee, even decaffeinated, can aggravate ulcers and heartburn.

-- Drinking up to three cups a day does not seem to increase heart disease risk. But four or more (decaf or not) boosted men's rate of heart disease 30 percent and women's 60 percent in a study of more than 100,000 people by Arthur Klatsky of Kaiser Permanente Medical Center, Oakland, Calif.

-- Relax: Filter-drip coffee doesn't raise cholesterol. Drinking coffee does not increase cancer risk, with the possible exception of bladder cancer.

Coffee usually is a brain sharpener, not a health risk, studies show.

Tea -- black or green, not herbal -- may help prevent cancer, heart disease, cavities, early aging

Caffeine headache

Americans average 2.5 cups of coffee a day. To kick caffeine, slowly cut down over a week to avoid withdrawal aches, fatigue or depression. Many post-surgery headaches (long blamed on anesthesia) stem from pre-surgery bans on caffeine, a new study has found.

THE 3-MINUTE ANTIOXIDANT BREW

To extract maximum antioxidants, let black or green tea steep for at least 3 minutes. How to brew:

1 heaping tsp. of loose tea or 1 tea bag per cup of fresh cold water

Bring water to a boil. Place loose tea or tea bags in a teapot. Add hot water. Steep for at least 3 minutes. Remove the tea bags or pour the tea through a strainer to remove leaves.

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

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