Medical after-effects of tea have been analyzed ever since the initial infusions of Camellia sinensis about 4700 years back in China. The renowned emperor Shennong stated in The Divine Farmer’s Herb-Root Classic that Camellia sinensis infusions were helpful for treating problems including tumours, abscesses, bladder ailments, and problem.
Catechins are contained by tea, a form of antioxidant. In a freshly chosen tea leaf, catechins may write around 30% of the dry weight. Catechins are highest in concentration in white and green teas, while black tea has substantially fewer because of its oxidative planning. Research by the U.S. Department of Agriculture has suggested that quantities of anti-oxidants in green and black tea don’t differ greatly, with green tea (http://en.wikipedia.org/wiki/Health_effects_of_tea) having an oxygen radical absorbance potential (ORAC) of 1253 and black tea an of 1128 (measured in molTE/100g). The levels of carbs, fat, and protein present in tea are minimal. Although tea includes various kinds of tannin and phenolics, tannic acid doesn’t be contained by tea. Tannic acid is not a suitable standard for almost any type of tannin analysis due to the poorly defined composition.
Theanine and coffee
Tea also contains theanine and the stimulant caffeine at about 3% of its dry weight, converting to between 30 mg and 90 mg per 8 oz (250 ml) cup according to variety, brand and brewing method. Tea also contains small amounts of theobromine and theophylline. Due to present day environmental pollution fluoride and aluminium have also been found to occur in tea, with certain kinds of brick tea produced from old leaves and stems having the highest levels. This does occur due to the tea plant’s large sensitivity to and consumption of environmental pollutants. Dry tea has more caffeine by weight than coffee; none the less, more dried coffee can be used than dry tea in preparing the beverage, which ensures that a cup of brewed tea contains even less caffeine than a cup of coffee of the exact same size.
Know more about green tea health benefits:
Health Effects of Green Tea
Why Should I Drink Green Tea?
Page 2: Study: Black Tea Helps Prevent Cavities - ABC News
Benefits of Green Tea - Yahoo! Voices - voices.yahoo.com
green tea: Definition from Answers.com