Considered by many to be one of nature's healthiest beverages, green tea is rich in antioxidants that could help fight off heart disease and cancer. Made from unfermented leaves of the Camellia sinensis plant, green tea is also low in caffeine (offering about 8 to 30 mg per cup, compared to 100 to 350 mg per cup of coffee) and contains the amino acid L-theanine (shown to induce relaxation and relieve stress in preliminary research).
Now, a number of studies are exploring the benefits beyond green tea's heart-healthy, anti-cancer, stress-reducing effects. Here's a look at some of the most promising findings so far.
1) Healthy Teeth and Gums
In a 2009 study, scientists sized up the periodontal health of 940 men and found that those who drank green tea on a regular basis had healthier gums than participants who skimped on the drink. For every cup of green tea sipped daily, in fact, there was a significant decrease in several indicators of periodontal disease (such as bleeding upon probing of the gum tissue).
Past research also indicates that drinking green tea may help you avoid tooth erosion.
2) Stroke Prevention
Another 2009 study suggests that drinking green tea each day can significantly slash your risk of stroke (the third leading cause of death in the United States). In reviewing nine studies on a total of nearly 195,000 people, researchers found that three daily cups of tea reduced stroke risk by 21%. What's more, consuming three more cups a day appeared to decrease stroke risk by an additional 21%.
3) Better Brain Power
Gulping green tea could preserve your brain power as you age, according to a 2006 study. The study's authors looked at tea consumption among 1,003 Japanese people (ages 70 and up), finding that those who drank the most green tea were the least likely to show signs of weakened brain function. For instance, study members who had a cup of green tea four to six times weekly were 38% less likely to display signs of cognitive impairment than those who drank green tea less than three times per week.
Arab L, Liu W, Elashoff D. "Green and Black Tea Consumption and Risk of Stroke. A Meta-Analysis." Stroke 2009 [Epub ahead of print]
Bassiouny MA, Kuroda S, Yang J. "Topographic and radiographic profile assessment of dental erosion. Part III: Effect of green and black tea on human dentition." General Dentistry 2008 56(5):451-61.
Kushiyama M, Shimazaki Y, Murakami M, Yamashita Y. "Relationship between intake of green tea and periodontal disease." Journal of Periodontology 2009 80(3):372-7.
Kuriyama S, Hozawa A, Ohmori K, Shimazu T, Matsui T, Ebihara S, Awata S, Nagatomi R, Arai H, Tsuji I. "Green tea consumption and cognitive function: a cross-sectional study from the Tsurugaya Project 1." American Journal of Clinical Nutrition 2006 83(2):355-61.