Drinking oolong tea can help burn fat while you sleep, study shows

TSUKUBA, Japan — Want to lose weight but don’t have the time to exercise all day? A new study finds a nice cup of tea can help do it for you — while you sleep! Researchers from the University of Tsukuba in Japan say drinking oolong tea increases the breakdown of fat and continues to work even when a person is resting.

Professor Kumpei Tokuyama finds drinking two cups of oolong tea each day significantly stimulates fat burning processes in the body.

“Like all teas, oolong contains caffeine, which impacts energy metabolism by increasing our heart rate. However, studies suggest that tea consumption may also increase the breakdown of fat, independent of the effects of caffeine,” the senior study author explains in a university release. “We therefore wanted to examine the effects of oolong consumption versus caffeine alone on energy and fat metabolism among a group of healthy volunteers.”

What’s so different about oolong tea?

Although all types of tea come from the same plant, Camellia sinensis, their degree of oxidation determines what variety ends up in your cup. This chemical process is what turns tea leaves black.

Green tea, for example, does not undergo oxidation and has a mild flavor. Black tea on the other hand comes from tea leaves which undergo complete oxidation. Oolong falls somewhere in the middle. Its leaves are partially oxidized and researchers say the tea displays characteristics of both green and black tea. Health experts consider tea to be extremely health, especially green tea, but study authors say oolong has been more of a mystery until now.

Burning fat without losing any sleep

The study tested a group of healthy volunteers drinking either oolong tea, pure caffeine, or a placebo for two weeks. The results reveal participants drinking oolong tea or caffeine increased their breakdown of fat by 20 percent compared to the control group. Researchers note that the effects of oolong tea keep going after the participant goes to sleep.

Surprisingly, neither tea nor caffeine causes an increase in energy expenditure. Study authors say this shows the group developed a tolerance to the caffeine present in both drinks over the two weeks.

Since caffeine typically affects sleep, and losing sleep can impact your metabolism, the study also examined each person’s sleep quality during the experiment. Despite caffeine’s reputation for keeping people awake, researchers discovered there was no difference in the sleep patterns of the test group or the placebo group. Therefore, the team believes drinking a cup of oolong tea won’t keep you up all night and may help burn off some of those extra holiday pounds.

“The stimulatory effects of oolong tea on fat breakdown during sleep could have real clinical relevance for controlling body weight. However, we need to determine whether the effects we observed in the 2-week study translate into actual body fat loss over a prolonged period. In addition, we want to trial a decaffeinated oolong tea to better distinguish the effects of caffeine from other components of tea, which will help us understand exactly how oolong helps with fat breakdown,” Prof. Tokuyama concludes.

The study appears in the journal Nutrients.