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The active substances in green tea

Green tea contains various active substances, such as carbonydrate, protein, fat, vitamins, minerals, catechin (tannin) and caffeine. Dried 10g green tea contains 2,200mg potassium, 44mg calcium, 280mg phosphorus, 20mg iron, 3mg sodium, 250mg vitamin C, 13mg carotine, 65.4mg vitamin E (effective), 1.4mg vitamin B2, and 4mg niacin. Those active substances contained in green tea can be fully taken by eating but not by drinking. It is because some of the substances cannot be released in the water. Diminutive amount of potassium, manganese, zinc, copper and selen can be released in the water. The suggested amount of vitamin C can be consumed by drinking 10 cups of green tea a day. Oolong tea or black tea, and Pu-er tea loose large amount of vitamin C during the fermentation process.

(Mamoru Isemura)