Oolong Tea to Lose Weight

Oolong, occasionally called Wu Long, is a variety of tea particular to China and Taiwan. It is made from the leaves of the camellia sinensis tree, as are white, green and black teas. Traditional Chinese medicine has long held that oolong tea is beneficial for weight loss and heart disease.

Manufacture

There are over 3,000 varieties of tea produced worldwide through differing methods of processing camellia sinensis. Oolong tea is referred to as "semifermented" because it is allowed a brief period of oxidation as opposed to unfermented white and green tea or the fully fermented black teas. Oolong tea can be between 10 percent and 70 percent fermented based on the region.

Expert Insight

A study performed by Japanese researchers published in The Journal of Medical Investigation tested the effects of both oolong and green tea on the energy expenditure of 11 healthy women. The results showed that oolong tea increased energy expenditure by 10 percent while green tea had only produced a 4 percent increase.

Another study published in the International Journal of Obesity directly challenged the anti-obesity effects of oolong tea on mice fed a high-fat diet. The mice were given oolong tea for 10 weeks. The study found that "Oolong tea prevented the obesity and fatty liver induced by a high-fat diet."

How It Works

Oolong tea contains approximately half the caffeine and EGCG of green tea but double the concentration of polymerized polyphenols. It is thought to be the polyphenol compounds in oolong tea, not the caffeine, that contribute to weight loss. The exact mechanism for how the polymerized polyphenols improve energy expenditure is unclear.

Varieties

The color, flavor and caffeine content of oolong tea varies based on the region of origin as well as the processing technique. Traditionally, oolong teas produced in Taiwan undergo a longer fermentation than those from China. These Taiwanese varieties tend to be darker in color and have a stronger flavor. Taiwan is also principally responsible for the production of pouchong oolong teas, which experience an extremely short fermentation and so have a light flavor. Pouchong teas are generally used as the base for scented teas.

Warning

Oolong tea contains caffeine and tannins, which can irritate pre-existing stomach conditions such as heartburn and ulcers. Some people also experience allergies to these compounds. All teas, including oolong, can have negative interactions with certain medications. Consult your doctor.