The question
What kind of tea is the best choice? Black, green or white?
The answer
Each one of these types of tea is a healthy choice. All teas come from the leaves of an evergreen plant called Camellia sinensis, but how those leaves are processed determines whether you end up with black tea, green tea or white tea – and the concentration of antioxidants you get. (One exception: Herbal tea isn’t considered a true tea because it’s not made from Camellia sinensis. Herbal teas are brewed from flowers, grasses, and herbs.)
Green tea is made from mature tea leaves that are not allowed to oxidize or ferment; the leaves are quickly steamed or heated and then dried. White tea is produced in a similar manner to green tea except that younger leaves and buds are used. To make black tea, the leaves are first rolled or broken to release some of the juices necessary for fermentation. The leaves are then allowed to fully ferment before they’re heated and dried.
Fresh tea leaves are an incredibly rich source of phytochemicals called catechins, phytochemicals that have potent antioxidant properties. In fact, tea is one of the highest sources of antioxidants in the North American diet. The main catechin found in tea is called epigallocatechin gallate (EGCG), an antioxidant that appears to lower the risk of heart disease and numerous types of cancer.
Because green tea has not been fermented, it contains the highest concentration of catechins – about three times the quantity of catechins found in black tea. Steaming the leaves during green tea production inactivates the enzyme that triggers fermentation and the subsequent loss of catechins. White tea is also steamed and, as a result, retains high concentrations of antioxidants present in the leaves. Black tea, which is fully fermented, contains the least catechins although it is still a very good source.
Regardless of the type of tea you choose, I recommend using loose tea leaves rather than tea bags. A cup of brewed loose leaf tea is much better-tasting than one brewed from bags and it contains more antioxidants. That’s because a whole tea leaf has more surface area for hot water to extract flavour and antioxidants from the leaf. Tea bags don’t have as much surface area for this extraction.
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