QUESTION: I am considering switching from drinking coffee to drinking tea every day for my health, or is it just a fad? Can you tell me exactly what health benefits I might expect?
ANSWER: A cup of tea is relaxing, refreshing and, unlike so many other indulgences, healthy. It’s hardly a fad. Tea is the most popular beverage worldwide, aside from water, and has a history of thousands of years.
The Chinese wrote of the curative properties of tea in the eighth century, and when the British and Dutch took the newly discovered beverage back to Europe in the 17th century, they extolled tea’s healthful effects.
Numerous studies over the past decade provide scientific data to support the health claims and identify the specific chemicals that make tea good for us. There is solid evidence to back the claim that regular tea drinking can lower the risk of heart disease and certain cancers, improve cholesterol levels, increase bone density and reduce inflammation that leads to arthritis.
Many studies of tea have focused on green tea, although scientists now believe that most of the benefits observed in green tea also apply to black, white and red tea.
Green tea has extremely high concentrations of an antioxidant known as EGCG (epigallocatechin gallate). Antioxidants help rid the body of free radicals, preventing damage to cells that cause cancer and other diseases. EGCG is the major catechin in green tea and is 100 times more powerful than vitamin C when it comes to zapping free radicals and 25 times more effective than vitamin E.
Lab studies show that EGCG is capable of killing cancer cells in a test tube. A Japanese study of women with breast cancer found that after the treatment phase, early-stage breast cancer spread less rapidly in women with a history of drinking five or more cups of green tea per day. A recent study published in the International Journal of Cancer reports the strongest evidence to date that green tea can protect against all stages of prostate cancer.
Other types of cancer shown by either animal, lab or observational studies to be inhibited by tea consumption include cancers of the skin, rectum, stomach, bladder and liver.
Tea is rich in polyphenols. In green tea they’re concentrated in the catechins. Green tea retains catechins because it is steamed shortly after picking. Black and oolong teas are dried after picking, a process that causes them to lose catechins, but they’re not without polyphenols. White tea is the least processed form and contains a higher proportion of buds covered with fine, “silvery” hairs that give a light, white color to the tea. It has a sweeter flavor than green or black tea and is shown to be more protective than green tea in inhibiting cell mutations that can lead to cancer and at killing bacteria that cause strep infections, pneumonia and dental cavities.
Although much of the research related to health has been conducted on green tea, researchers believe that black tea, the kind most often consumed by Americans and Europeans, provides many of the same health properties.
Antioxidants in tea have been shown to promote heart health in a number of ways, lowering total cholesterol, triglycerides and LDL levels and decreasing the risk of heart attack and stroke.
Research also suggests that tea may help improve bone-mineral density. Low bone-mineral density is associated with the development of osteoporosis.
Tea is an easy and inexpensive addition to your diet, costing only pennies per cup. If you drink it black or with a squeeze of lemon, it doesn’t add calories.
Some early studies suggested that adding milk to tea (the way most people in the United Kingdom drink their tea) dampens the antioxidant activity. Scientists now are leaning toward thinking tea is beneficial even if you use milk. Adding sugar or lemon doesn’t affect the health benefits, although sugar will add calories to this otherwise calorie-free brew.
The wealth of studies touting the health benefits of tea need to be confirmed by scientifically controlled human trials, some of which are now under way. Lab, animal and observational studies all point toward a very favorable profile for tea, however, suggesting that regular tea drinking can help protect against cancer, strengthen bones, lower the risk of heart disease and generally fight infection and inflammation. All this in a relaxing, refreshing cup of tea! Sip to your heart’s content.
(azcentral.com, Jan 2005 by Alice Kraft)
Alice Kraft is a registered dietitian with Sun Health Community Education and Wellness Centers.