Clearly, green tea is a powerful weapon against several deleterious diseases and conditions. But how about black tea? Does it also promote good health?
Black tea has long been used as a medicine, a pleasing beverage, and a psychologically soothing tonic. Not surprisingly, scientists have discovered that black tea does have several health benefits, although they are not nearly as wide-ranging and powerful as those of green tea. That’s because most of green tea’s health-promoting characteristics come from catechins, which are mostly oxidized into theaflavins and thearubigens during the manufacture of black tea. These new com-pounds do have some of their own health benefits, but they can’t compare with the wide-ranging effects of green tea’s catechins, especially the powerful EGCg.
Still, the theaflavins and thearubigens are strong antioxidants, and worthy of serious attention. Let’s take a look at several of black tea’s health benefits.
Tea, Heart Disease, and Stroke
A Dutch study completed in 1990 followed 805 men, aged sixty-five to eighty-four, for five years, studying their intake of the antioxidant-rich flavonoids (found in abundance in tea, vegetables, fruits, and wine)and the effect on their death rate from coronary heart disease. Most of the flavonoids in the men’s diets (61%)came from black tea, while 13% came from onions and 10% from apples. After five years, the study found that there was a strong link between a high flavonoid intake and a lower risk of death due to heart disease. This study certainly suggests that black tea has a protective effect on the heart.
A similar study, again from the Netherlands, this time lasting for fifteen years, found that those with a high intake of flavonoids had a 73% lower risk of stroke. When researchers adjusted the results to allow them to look at the effects of tea alone, they found that those who drank more than 4.7 cups per day had a 69% reduced risk of stroke, compared to those who drank less than 2.6 cups. The researchers concluded that the habitual intake of flavonoids and their major source (tea)could protect against strokes.
Tea and the Liver
It appears that both black and green tea can help the body purify itself. Both teas were found to be equally powerful in increasing the metabolic processes by which rat livers detoxify carcinogens and other toxins. This makes the liver better able to inactivate these poisons and excrete them, theoretically reducing the risk of cancer and other ailments.
Tea, the Antioxidant
Even though black tea lacks the powerful antioxidant action of the catechins, its theaflavins and thearubigens exert their own mighty antioxidant punch. Scientists at Rutgers University found that gallic acid, a substance found in black tea, could strongly inhibit the oxidation of lard. A Japanese study done in 1994 found that theaflavins helped protect the membranes of rabbit blood cells from oxidation damage, while warding off much of the damaging effects of hydrogen peroxide on DNA. And yet another Japanese study found that theaflavins and thearubigens in black tea inhibited the oxidation of fatty substances in rat livers just as well as EGCg, and even better than vitamin E or vitamin C.
This ability to block the oxidation of fats is probably the reason that black tea lowered the risk of strokes and death from heart disease in the Dutch studies. The flavonoids also blocked the oxidation of the LDL, which has long been considered to be one of the early events in coronary artery disease.
Tea and Kidney Stones
Although patients with kidney stones are almost always advised to increase their intake of fluids, only recently have researchers tried to figure out just which drinks were most likely to prevent the stones–or cause them to form in the first place. At the Johns Hopkins University School of Hygiene and Public Health, scientists studied the relationship between twenty-one different beverages and kidney stone formation in 45,289 men. (Ranging in age from forty to seventy-five, none of them had a history of kidney stones.) The results were intriguing, showing that each 8-ounce serving of black tea consumed daily led to a 14% decrease in the risk of stone formation.
Tea and Skin Inflammation
Black tea is high in astringent tannins, which can help relieve skin inflammation. Cool, wet tea bags have long been applied to soothe burns, and a quart of strong black tea added to a lukewarm bath can be an effective remedy for sunburn.
Tea and Tooth Decay
All teas are good sources of fluoride, the mineral that hardens tooth enamel. And even though black tea contains only about half the amount of fluoride found in green tea, just one cup per day may confer powerful protection against cavities. Like green tea, black tea can interfere with the formation of plaque and fight oral bacteria, and is most effective when sipped at the end of a meal.
Tea Is Good for You
In short, it appears that any brew made from the Camellia sinensis bush is good for you. Although black tea doesn’t appear to wield quite the health-promoting punch that green tea does, it certainly qualifies as a ‘steaming cup of medicine'” all on its own.