Tea Lowers LDL Cholesterol and Cancer Risk

Solid evidence from two new placebo-controlled trials adds to a growing body of research that shows tea lowers LDL cholesterol levels and can prevent DNA damage. Damaged DNA is the first step in the development of cancer and is also associated with heart disease.

Tea may soon be added to the list of fruits and vegetables experts urge Americans to eat as often as possible to reduce their risk of disease, the researchers who produced these studies told a meeting sponsored by the US Department of Agriculture, the Tea Council, the American Cancer Society and other groups.

Tea contains a type of powerful phytochemical antioxidant called catechins. "It's taken about 30 years to fully appreciate the importance of these compounds," said Jeffrey Blumberg, a nutritionist at Tufts University in Boston, who acts as an adviser to both the US Food and Drug Administration and the Tea Council.

Practical Tips

With the help of the World's Healthiest Foods, you won't have to wait another day to begin reaping the many health benefits offered by teas. Here are a few of theWorld's Healthiest Foods suggestions for enjoying tea:

• Steep tea for at least 3 minutes to ensure the release of its beneficial compounds. Steeping longer than 3 minutes will produce a more catechin-rich, but bitter tea.
• To counteract any bitterness and to enjoy boost your beverage's antioxidant benefits, sweeten your tea with a spoonful of honey.
• Not yet a tea drinker? Try chai, a delightful blend of tea with milk and spices, including cinnamon, ginger, cardamom, cloves, black pepper, and others. Not only do they please the tastebuds, but each of these spices also packs its own antioxidant punch. Already prepared chai is available at most groceries; it can be found in boxes like those in which soy milk is often sold.
• Even better, make your own pot of chai. For two cups of chai, put 1-1/2 cups of water in a pan. Add a 1-inch stick of cinnamon, 8 pods of cardamon, 8 cloves, several twists' worth of ground black pepper, and a 3/4 inch piece of finely chopped ginger. Bring to a boil, turn the heat to low, cover and let simmer for 10 minutes. Add 2/3 cup of milk, 1-1/2 tablespoons of honey, and simmer for 2-3 minutes. Add 3 tea bags or 3 teaspoons loose tea, cover, and turn off the heat. Let sit for 2 minutes, strain the tea into 2 cups and enjoy.

To learn more about any of these spices, truly among the World's Healthiest Foods, simply click on its highlighted name above.

Research Summary

The study to show tea's beneficial effects on cholesterol was conducted by Joseph Judd acting director of the USDA's Beltsville Human Nutrition Research Center, Maryland, and his colleagues. The subjects, 8 men and 8 women, agreed, for a period of 3 weeks at a time, to eat and drink only what they were given at the Beltsville lab. Their diet included 5 cups each day of either tea or a placebo-beverage flavored like tea. When tea-drinking subjects' blood lipids were measured, researchers found an up to 10% lowering of LDL, (low density lipoprotein, the "bad" cholesterol). Overall, the subjects' total cholesterol was an average of 6% lower during the 3 weeks they were drinking tea. And tea drinking only produced a drop in levels of LDL cholesterol, while leaving levels of beneficial HDL cholesterol constant.

The second study was led by Dr Iman Hakim at the University of Arizona and the Arizona Cancer Center. Dr. Iman Hakim tested 140 smokers to see if drinking tea would affect their levels of chemicals associated with DNA damage. This was evaluated by looking at a chemical marker of DNA damage in cells called 8-OHdG (8-hydroxy-2'-deoxyguanosine), which is excreted in urine. (Deoxyguanosine (dG) is a constituent of DNA and 8-OHdG is produced when free radicals oxidize dG).

Study subjects were asked to eat whatever they normally ate and to just add tea to their diet. For 4 months, these volunteers drank either green tea, black tea or water. Hakim's team tested their urine for levels of 8-OHdG.

"What we found was a 25% decrease (of 8-OHdG) in the green tea group," said Dr. Hakim. No changes were seen in the people who drank black tea or water. "We think green tea, in our group of smokers, is associated with a reduction of oxidative stress"" Hakim said.

Although more research is needed to see if lowering levels of 8-OHdG, or other markers of DNA damage, is actually associated with a lower risk of cancer, in the scientific community, many think tea can reduce the risk of cancer because it is loaded with phytochemicals. Phytochemicals provide a wide range of antioxidant molecules that counteract the damage done to DNA by free radicals, the electron-hungry molecules produced in the body by sunlight, chemicals, many foods and even the basic metabolic processes of living. When free radicals react with and steal an electron from DNA, the resulting damage to the cell's genetic template can impair normal cellular activity and possibly lead to cancer.

McKay DL, Blumberg JB. The role of tea in human health: an update. J Am Coll Nutr 2002 Feb;21(1):1-13. Fox, M. Tea may reduce risk of cancer, heart disease:Forum, Reuters Health, Sept. 25, 2002.