"Drink tea if you enjoy it, in moderation, and not because you're taking it as a medicine," says Dr. Sesso. Stirring in a little sugar is fine, but if you add a few heaping teaspoons of sugar, you're probably canceling out tea's possible benefits, he notes. And beware of the sugar found in many bottled teas, some of which contain as much as nine teaspoons of sugar per serving—almost as much as colas and other soft drinks. Check bottled tea labels and choose only pure, unadulterated tea—or save money and brew your own at home.
Matcha leaves are grown on green tea bushes kept under shade. The shade increases the amount of chlorophyll content in the leaves, which is what makes them bright green and full of nutrients. The leaves are picked by hand and the stems and veins are removed. According to Cheadle, the leaves are traditionally ground by granite stones into a super fine powder. “It takes an hour to grind the leaves, and it’s done in the dark to protect the nutrients,” she says.
Although numerous claims have been made for the health benefits of green tea, human clinical research has not provided conclusive evidence of any effects. In 2011, a panel of scientists published a report on the claims for health effects at the request of the European Commission: in general they found that the claims made for green tea were not supported by sufficient scientific evidence. Although green tea may enhance mental alertness due to its caffeine content, there is only weak, inconclusive evidence that regular consumption of green tea affects the risk of cancer or cardiovascular diseases, and there is no evidence that it benefits weight loss.
Indigenous to the Western Cape of South Africa, rooibos (Aspalathus linearis) is a shrub with long, needle-shaped leaves that turn red upon fermentation. When you drive through the countryside north of Cape Town, you see rooibos everywhere. Rooibos is a traditional beverage of the native Khoi people of the Cape area, though it has become more popular in recent years due to word spreading about its high antioxidant value. Traditionally, the native people harvest the leaves, bruise them with hammers, ferment them and dry them. The result is a red, astringent tea that refreshes and does not cause jitters.
Like black and green tea, rooibos is rich in polyphenols, such as rutin and quercetin. Cell and animal studies, mostly from South Africa, have shown that rooibos extracts have antioxidant, immune-stimulating, and anti-cancer properties. But studies of rooibos tea in people are limited. There’s little or no evidence to back claims that it relieves constipation, headaches, eczema, asthma, insomnia, high blood pressure, mild depression, ulcers, diabetes, and so on.
A book written by Lu Yu in 600-900 AD (Tang Dynasty), "Tea Classic" (simplified Chinese: 茶经; traditional Chinese: 茶經; pinyin: chájīng), is considered important in green tea history. The Kissa Yojoki (喫茶養生記 Book of Tea), written by Zen priest Eisai in 1211, describes how drinking green tea may affect five vital organs, the shapes of tea plants, flowers and leaves, and how to grow and process tea leaves.
Unlike traditional green tea, matcha preparation involves covering the tea plants with shade cloths before they’re harvested. This triggers the growth of leaves with better flavor and texture, which are hand selected, steamed briefly to stop fermentation, then dried and aged in cold storage, which deepens the flavor. The dried leaves are then stone-ground into a fine powder.
Certain studies indicate that intake of flavan-3-ols and/or anthocyanidins found in green tea may improve glycemic control and help normalize blood sugar levels. Due to its anti-inflammatory properties, green tea is believed to be beneficial for those who are at-risk or diagnosed with type 2 diabetes. Green tea’s catechins, especially EGCG, appear to have anti-obesity and antidiabetic effects.
Jump up ^ Iswaldi, I; Arráez-Román, D; Rodríguez-Medina, I; Beltrán-Debón, R; Joven, J; Segura-Carretero, A; Fernández-Gutiérrez, A (2011). "Identification of phenolic compounds in aqueous and ethanolic rooibos extracts (Aspalathus linearis) by HPLC-ESI-MS (TOF/IT)". Analytical and Bioanalytical Chemistry. 400 (10): 3643–54. doi:10.1007/s00216-011-4998-z. PMID 21509483.
Clinical studies suggest that green tea may boost your metabolism and help you burn fat. Green tea can also help you lose weight and lower your risk of becoming overweight or obese. Much of this effect is likely due to caffeine, but other compounds in tea may also contribute to this effect. By helping you selectively burn the fat you have stored in your body for energy, green tea may help you feel fuller and maintain a more steady energy level, resulting in less hunger cravings and less calories consumed.
The antioxidants present in rooibos tea slow down the aging process and also boost the strength of the immune system. Researchers at Nelson Mandela Metropolitan University in South Africa found that the local herb helps slow down the degeneration of fat cells, thus inhibiting the formation of wrinkles. Antioxidants in the tea seek out free radicals that damage the skin, hair, bones, and other organ systems by making them vulnerable to diseases and degeneration.