Pu-Erh tea really works: extracts from this Chinese tea promote weight loss. Japanese researchers at Fukuoka University have demonstrated the slimming effects of Pu-Erh tea in a human study, published recently in Nutrition.
Pu-Erh tea comes from the Yunnan highlands of China. It is black tea that is created by drying green tea leaves at a high temperature and then fermenting them in a humid environment using Aspergillus niger. Pu-Erh tea contains relatively high amounts of gallic acid
Water-based Pu-Erh extracts consist for about three percents of this phenol, and researchers suspect that gallic acid is the most active ingredient in Pu-Erh tea. The compound reduces the production of the enzyme lipase by the pancreas, and as a result Pu-Erh tea inhibits the absorption of fat, in animal studies. [Phytother Res. 2008 Oct;22(10):1275-81.] Another possible mechanism is that Pu-Erh extracts block the enzyme that converts nutrients into fat in the liver. [Oncol Res. 2005;16 (3):119-28.]
Previously published human studies have shown that Pu-Erh reduces the concentration of 'bad cholesterol' LDL, triglycerides and that it also reduces weight. [Nutr Res. 2008 Jul;28(7):450-6.] [Ann Nutr Metab. 2008;53(1):33-42.]
The Japanese gave 18 slightly overweight subjects, with a BMI of 26, one gram a day of Pu-Erh extract for a period of 12 weeks. The extracts were packed in sachets and produced by Nippon Supplement, the sponsor of the study. Three times a day the subjects dissolved the contents of a sachet in a glass of warm water and drank it at the mealtime. Eighteen subjects in the control group were given a product that contained no Pu-Erh tea.
The subjects were in their early fifties, and both men and women took part. Their average weight was 74 kg. They were all put on a similar diet, which provided 30 calories per kg bodyweight.
After 12 weeks the subjects in the Pu-Erh group had lost slightly more weight. The subjects in the control group had lost about a kilogram. In the four weeks after the Pu-Erh course the kilograms lost stayed off.
Most fat was lost in the abdomen, and to a lesser extent from the subcutaneous fat. According to the Japanese, this is encouraging. There are indications that abdominal fat carries more health risks than subcutaneous fat.
The Japanese report no negative side effects.
Nutr Res. 2011 Jun;31(6):421-8.