Multiple cups of green tea are good for you, studies indicate.
By Jasminee Sahoye
Green tea has been used by people around the world for years and many Caribbean people have been drinking it without realizing that it contains disease-fighting properties.
Studies have found an association between consuming green tea and a reduced risk for several cancers, including, skin, breast, lung, colon, esophageal and bladder.
Some additional benefits for regular consumers of green and black teas include a reduced risk for heart disease. The antioxidants in green, black and oolong teas can help block the oxidation of LDL (bad) cholesterol, increase HDL (good) cholesterol and improve artery function.
A number of studies have looked at possible links between green tea and cardiovascular disease.
A study of 40,530 Japanese adults found that participants who drank more than five cups of green tea a day had a 26% lower risk of death from heart attack or stroke and a 16% lower risk of death from all causes than people who drank less than one cup of green tea a day.
A recent set of observational studies conducted in green tea drinkers and five studies in black tea drinkers found that people who drank the most green tea had a 28% lower risk of coronary artery disease than those who drank the least green tea. Black tea had no effect on heart risk.
A 2011 meta-analysis of 14 randomized, placebo-controlled clinical trials found that green tea significantly lowered LDL cholesterol and triglyceride levels. Many of the studies had been conducted with capsules containing catechins, the active polyphenols in green tea, rather than with the beverage itself.
“The limited data available on green tea support a potential association between green tea and beneficial properties in relationship to risk factors for cardiovascular disease,” says Kathy McManus, director of the department of nutrition at Brigham and Women’s Hospital.
Meanwhile, a Chinese study published recently in the Archives of Internal Medicine showed a 46%-65% reduction in hypertension risk in regular consumers of oolong or green tea, compared to non-consumers of tea.
The Harvard health publication states drinking a cup of tea a few times a day appears to absorb antioxidants and other healthful plant compounds.
In green tea-drinking cultures, the usual amount is three cups per day. Experts say to allow tea to steep for three to five minutes to bring out its catechins.
Green tea is the best food source of a group called catechins. In test tubes, catechins are more powerful than vitamins C and E in halting oxidative damage to cells and appear to have other disease-fighting properties.
The best way to get the catechins and other flavonoids in tea is to drink it freshly brewed. Decaffeinated, bottled ready-to-drink tea preparations, and instant teas have less of these compounds.
Tea can impede the absorption of iron from fruits and vegetables. Adding lemon or milk or drinking tea between meals will counteract this problem.
Studies on green tea’s impact on cancer have been mixed. But green tea is known to aid healthy cells in all stages of growth. There are some clues that green tea may help destroy cancer cells but that research is still in its early stages, so you shouldn’t count on green tea to prevent cancer. In fact, the National Cancer Institute’s web site says it “does not recommend for or against the use of tea to reduce the risk of any type of cancer.”
“It’s the healthiest thing I can think of to drink,” says Christopher Ochner, PhD. He’s a research scientist in nutrition at the Icahn School of Medicine at Mount Sinai Hospital.
Green tea has been shown to improve blood flow and lower cholesterol. A 2013 review of many studies found green tea helped prevent a range of heart-related issues, from high blood pressure to congestive heart failure.
What’s good for the heart is usually good for the brain; your brain needs healthy blood vessels, too. In one Swiss study, MRIs revealed that people who drank green tea had greater activity in the working-memory area of their brains. Green tea has also been shown to help block the formation of plaques that are linked to Alzheimer’s disease.