Even in traditional tea drinking countries like China and Japan, oolong tea has a well-known and lasting reputation for helping people to keep slim. Overall, oolong tea promotes weight loss through three different mechanisms, as seen below:
– Increasing basal metabolic rate
– Burning fat (through a process called lipolysis)
– Blocking dietary fat absorption
Again, the Chinese have long believed that oolong tea is beneficial in reducing and maintaining weight. In fact, a 1998 Chinese study involving 102 females showed that continuous consumption of oolong tea for six weeks resulted in a reduction of body weight – of course, this study spurred further research.
Subsequently, Dr. William Rumpler, a physiologist at the US Agriculture Research Services’ Diet and Human Laboratory, investigated the ancient Chinese belief that oolong tea is effective in controlling body weight. The 2001 study measured how oolong tea influences energy expenditure (EE) and included 12 male volunteers who were given 4 separate beverage formulas over three consecutive days. The four beverage formulas were: 1) full strength oolong tea, 2) caffeinated water with caffeine equal to full strength oolong tea, 3) half strength oolong tea and 4) non caffeinated water.
After twenty-four hours, the energy expenditure (EE) of the participants was measured and resulted in:
|•||EE levels of about 3% higher when they drank either the full strength oolong tea or the caffeinated water versus the non caffeinated water.|
|•||Participants burned an average of 67 more calories per day when drinking the full strength oolong tea.|
|•||Participants increased fat oxidation (‘lipolysis’ or fat burning) by a whopping 12% after consuming the full strength oolong tea versus the caffeinated water.|
|•||This data confirms that a component other than caffeine is responsible for promoting the preferential use of fat as an energy source.|
The increase in fat oxidation in this study is amazing! Drinking oolong tea can actually tell your body to burn fat as an energy source!
Moreover, a 2003 Japanese study went one step further by comparing the benefits of oolong tea and green tea regarding weight reduction. In this well controlled study, eleven healthy young female student participants received three different beverage formulas: 1) oolong tea, 2) powdered green tea leaves and 3) water.
After all of the measurements were taken, the results determined that:
|•||Oolong tea had higher energy expenditure (EE) levels from beginning to end and at intervals of 30, 60, 90 and 120 minutes.|
|•||EE levels peaked at 90 minutes for both oolong and green tea and remained at their respective levels until 120 minutes.|
|•||These results indicate that for up to two hours after consuming oolong tea, you will expend more energy than if you were to drink green tea or water.|
Additionally, the concentrations of caffeine, catechins, and other polyphenols were measured producing these intriguing findings;
|•||The caffeine content was much higher in the green tea versus the oolong tea.|
|•||The concentration of polymerized polyphenols was significantly higher in the oolong tea versus the green tea.|
These findings show that it’s the polymerized polyphenols that link tea to burning fat, not just the caffeine – again, the concentrations of polymerized polyphenols are highest in oolong tea. Furthermore, the rest of the chemical compounds compared in the oolong and green teas were similar or equal to one another with no marked differences – this reinforces the result that the polymerized polyphenols principally contributed to the lipolytic effect of oolong tea.
Finally, oolong tea’s effect on blocking the absorption of fats and carbohydrates is thought to play a key role in its weight reducing benefits – in fact, oolong tea is a popular accompaniment for greasy food in Asia for that very same reason. Now, scientists have proven that it is an effective fat blocker. A study conducted by the University of Tokushima found that drinking oolong tea can double the amount of fat being excreted. During the study, tweleve young Japanese adults participated in the 17-day program, consisting of 10 days of washout (drinking nothing but water) and 7 days of treatment (drinking oolong tea). The scientists found that fat excretion was twice as high for those who consumed oolong tea compared to the placebo.
Overall, oolong tea promotes weight loss through increasing basal metabolic rate (energy expenditure), increasing lipolysis, and blocking the dietary absorption of fat. Just by drinking this tasty brew, you can help yourself on the way to a healthier, slimmer you!