Tea may arguably be the most consumed beverage on the planet after water. Many cultures, including the Chinese, Japanese, English, and Indian consume tea on a daily basis. Whether white, green, oolong, black or other, research has found that tea offers remarkable health benefits, but may also have some drawbacks.
Lower Cancer Risk
According to the Harvard Women's Health Watch, a division of Harvard Medical School, the antioxidants in tea, called flavenoids, are largely responsible for tea's health-boosting properties.
A group of flavenoids called catechins help prevent oxidative damage to cells and give tea the power to reduce a person's risk of several types of cancer, including breast, bladder, skin, lung, colon and esophageal. Harvard states that in test tubes, catechins are more effective than either vitamin A or C at halting the damage of oxidation, a by-product of normal metabolism.
According to a 2004 study published in the "Archives of Internal Medicine," habitual consumption of green and oolong tea significantly reduced the risk of hypertension in Chinese volunteers. Hypertension, or high blood pressure, is a risk factor for strokes and heart attacks.
Additionally, the Harvard Women's Health Watch states that the antioxidants in green, black and oolong teas help block the oxidation of LDL cholesterol, increase HDL cholesterol and improve artery function. High LDL and low HDL are both risk factors for cardiovascular diseases such as atherosclerosis.
Decaffeinated, ready-to-drink and instant teas have fewer beneficial compounds and may not offer the same benefits as freshly-brewed tea.
According to MayoClinic.com, tea is a source of caffeine, a stimulant that can cause symptoms such as agitation, insomnia and excessive urination. Beverages containing caffeine may increase the production of stomach acid and worsen the symptoms of ulcers.
Because an increase in blood sugar may occur, people suffering from diabetes should monitor blood sugar levels when drinking tea.
In a 2010 article by Meredith Land of NBC News, urologist S. Alexis Gordon states that teas with higher oxalate content, such as restaurant brands and some black teas, may contribute to the formation of kidney stones. However, in a 2009 article by Chinese scientists published in the Royal Society of Chemistry journal "CrystEngComm," green tea was found to help prevent the formation of large kidney stones.