Oolong tea is what you usually get in Chinese restaurants, but don’t judge oolong on the basis of that tea, which is typically of low quality. The better oolongs are delicious. Many people in the Canada and the United States stick to green or white tea exclusively because they believe those varieties offer the most health benefits, but oolong has similar antioxidant properties. In China, oolong has a mystique and culture as rich as that of green tea in Japan.
The effect of oolong tea on blood sugar has been tested in several studies. Investigators with the U.S. Agricultural Research Service (ARS) conducted a pilot study using volunteers, all with type 2 diabetes. They found that by drinking six cups of oolong daily for eight weeks, the volunteers were able to lower their blood sugar levels by 15 to 20 percent.
Andrew Weil, M.D.
The Weight Loss Connection
The two main ways to reduce food related body weight are; increase energy expenditure (EE) and inhibit the absorption of nutrients, including fat and carbohydrates. Caffeine is a stimulant so it is widely accepted that the caffeine in tea increases metabolism, hence increasing EE.
Physiologist Dr. William Rumpler, of the US Agriculture Research Services' Diet and Human Laboratory, investigated the ancient Chinese belief that oolong tea is effective in controlling body weight. The study measured how tea influences energy expenditure (EE) and included 12 male volunteers who were given 4 separate beverage formulas over three consecutive days. The beverage formulas consisted of; 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.
The participants 24 hour EE was measured and resulted in;
• EE levels were 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 (fat burning) by a whooping 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 for energy! Scientists then speculated that caffeine combined with EGCGs worked together to increase fat oxidation. These findings show that it's the polymerized polyphenols, highest in oolong tea, that link tea to burning fat. Oolong tea's effect on blocking the absorption of fats and carbohydrates is thought to play a key role in its weight reducing benefits.
Beth Johnston, a tea importer and noted tea expert, publishes an informative monthly newsletter on tea, tea history, health and lifestyle enhancements.