The benefits of tea (green, black, even white!) have been talked about for
ages. And many ancient cultures have used tea in culinary and ritualistic
applications for centuries. With so many varieties, it could be confusing to
dig through all the information to find what their exact benefits are, and
whether some have more positive health impacts than others. So here's a
quick breakdown.
The average American drinks 155 cups of tea a year. Although the US ranks a
bit lower in tea consumption (it's number four), worldwide, tea is second
only to water as the world's most frequently consumed beverage. Tea's
popularity owes much to people's beliefs about its health benefits-verified
to some degree by recent studies.
Where Does All the Coloring Come From? .Green, black, white, and oolong tea
all actually come from the same plant. The different colors and tastes are
determined by the leaves' level of processing, country of origin, and
growing region.
In essence, all tea leaves are dried and heated. Leaves that are allowed to
ferment and oxidize yield black tea, green tea is not fermented, and oolong
falls somewhere between black and green tea in processing. White tea comes
from the unprocessed buds and possibly leaves.
Health Benefits .Studies suggests that all tea contains a major group of
antioxidants known as catechins, which help the body fight cell-damaging
unstable molecules called free radicals, which in turn, may cause cancer
cells to die. Green tea contains higher levels of antioxidants than black
tea, perhaps because of less processing.
According to the National Cancer Institute, studies have shown tea catechins
act as powerful inhibitors of cancer growth by removing free radicals before
cell injuries take place. In mice, this reduces the size of liver, skin, and
stomach tumors. However, to date, cancer studies involving humans have been
mixed. Some studies comparing tea drinkers to nondrinkers find the beverage
helps prevent cancer; others do not.
Aside from cancer-beating benefits, the American Academy of Family
Physicians has concluded green tea is effective in treating genital warts
and may help people lose weight, lower cholesterol, and reduce the risk for
stroke and heart disease.
Everything in Moderation.While no one's sure how much tea you need to drink
to reap its benefits, people in Asia tend to drink three or more cups a day
of green tea brewed using 1 to 2 teaspoons of dried tea in 8 ounces of
boiling water. One study found that steeping black or green tea for about
five minutes released more than 80 percent of its antioxidants. Instant iced
teas also contained few antioxidants, and bottles and cans of prepared green
tea contain various amounts of antioxidants, however, often with additional
ingredients. Green tea extract is also available in capsules. But since such
dietary supplements are unregulated, they may contain contaminants and
varying amounts of tea. Therefore, recommended doses are not certain.
Moderate tea intake is considered safe. However, drinking large amounts of
tea may make it harder for the body to absorb some medications and iron
supplements. The caffeine in tea can interact with medications, including
some pain relievers, blood thinners, anticoagulants, antacids, antibiotics,
and other drugs.
The main downside of drinking tea stems from ingesting too much caffeine.
That can lead to nausea, trouble sleeping, and frequent urination. People
who have anxiety attacks or irregular heartbeats should limit their intake.
Women who are breast-feeding or pregnant shouldn't drink large amounts of
tea due to its possible effects on the baby.
That said, people have been drinking tea for thousands of years with few
dangerous effects-and several potential benefits. Although further studies
are needed, drinking tea appears to be a low-risk, cost-effective, and
enjoyable complementary therapy worth cultivating.
Adapted from an article by Barbara Floria, senior writer for Vitality. For
more information, visit the National Center for Complementary and
Alternative Medicine at www.nccam.nih.gov.