molecules Review The Beneficial Effects of Principal Polyphenols from Green Tea, Coffee, Wine, and Curry on Obesity Tomokazu Ohishi 1,* , Ryuuta Fukutomi 2 , Yutaka Shoji 3 , Shingo Goto 4 and Mamoru Isemura 3 1 Institute of Microbial Chemistry (BIKAKEN), Numazu, Microbial Chemistry Research Foundation, Shizuoka 410-0301, Japan 2 Quality Management Div. Higuchi Inc., Minato-ku, Tokyo 108-0075, Japan;
[email protected] 3 Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka, Shizuoka 422-8526, Japan;
[email protected] (Y.S.);
[email protected] (M.I.) 4 Division of Citrus Research, Institute of Fruit Tree and Tea Science, National Agriculture and Food Research Organization (NARO), Shimizu, Shizuoka 424-0292, Japan;
[email protected] * Correspondence:
[email protected]; Tel.: +81-55-924-0601 Abstract: Several epidemiological studies and clinical trials have reported the beneficial effects of green tea, coffee, wine, and curry on human health, with its anti-obesity, anti-cancer, anti-diabetic, and neuroprotective properties. These effects, which have been supported using cell-based and animal studies, are mainly attributed to epigallocatechin gallate found in green tea, chlorogenic acid in coffee, resveratrol in wine, and curcumin in curry. Polyphenols are proposed to function via various mechanisms, the most important of which is related to reactive oxygen species (ROS). These polyphenols exert conflicting dual actions as anti- and pro-oxidants. Their anti-oxidative actions help scavenge ROS and downregulate nuclear factor-κB to produce favorable anti-inflammatory effects. Meanwhile, pro-oxidant actions appear to promote ROS generation leading to the activation 0 of 5 -AMP-activated protein kinase, which modulates different enzymes and factors with health beneficial roles.