Green Tea supplementation III: antioxidant, fat-burning, and weight loss promoting effects of green tea

Antioxidant activity

The polyphenols present in green have generated lots of interest by researchers, as polyphenols, a large class of compounds found in plants, are antioxidants which have been associated with decreased risk of a number of diseases. The particular array of polyphenols in green tea has been shown to have extremely potent antioxidant activity, most likely associated with the reduction in cancer risk and cardiovascular disease. One of the particular polyphenol compounds in green tea, a catechin called epigallocatechin gallate (EGCG) has been shown to be a powerful antioxidant in addition to having potent anticarcinogenic and anti-lipogenic activity. Also present in green tea are carotenoids, tocopherols, ascorbic acid (vitamin C), and minerals such as Cr, Mn, Se or Zn. Important anti-oxidants in their own right, it is likely that the presence of these non-phenolic antioxidants can actually support the anti-oxidant activity of the polyphenols in green tea, acting in a synergistic manner. Extensive research has on the antioxidant effects of green tea has shown that when combined with a balanced diet, the consumption of green tea on a daily basis can protect against oxidative damage so intimately associated with aging and disease.

Energy-promoting/fat burning effects

Green has been associated for some time with fat loss and improvements in body composition, most like attributed to the caffeine and theophylline content. Contrary to the any anti-caffeine propaganda you may have encountered, caffeine has been shown time and time again to promote lipolysis (i.e fat burning). Theophylline acts synergistically with caffeine to promote its effects, and additionally opens up the airway (theophylline was often prescribed as an asthma treatment years ago). While the caffeine and theophylline are certainly involved in the fat-burning ability of green tea, there are other mechanisms by which green tea encourages fat loss and decreased body fat storage. In vitro studies using both mouse and human preadipocytes (basically “precursor” fat cells) have shown that the EGCG in green tea not only inhibits adipogenesis (differentiation to a mature fat cell), but also causes the fat cells to die! While in-vitro studies rarely correlate nicely with in vivo effects, many studies have shown that in humans, green tea promotes body fat loss and thermogenesis by mechanisms independent of those attributed to its caffeine and theophylline content; most likely involving the catechin EGCG. It is likely that the combination of caffeine, theophylline, and EGCG act in a synergistic manner to induce weight loss and fat-burning. While there is no definitive amount of green tea needed to induce its weight loss and fat burning effects, EGCG has been shown to accumulate over time and we already know the half-lives of caffeine and theophylline. A good recommendation for the amount of green tea needed to elicit weight loss and all of the other reported benefits would be 2-3 6-ounce servings/day.

Summing it up...

Green tea has been shown to have a wide variety of significant health-promoting effects in humans, animals, and in vitro cell culture. The polyphenols present in green tea, particularly the catechin EGCG, have been shown to have anti-oxidant and anti-carcinogenic properties in addition to preventing cardiovascular disease and promoting weight loss. It is no mystery that health and fitness are two intimately related concepts; with greater fitness comes greater health and vice-versa. Anything we can do, whether it is through exercise, weight loss, diet, or supplement intake, to influence either of these will be sure to promote a long, healthy life. Pharmaceuticals, although necessary, are not without their problems. If diseases could be prevented before dangerous pharmaceuticals are needed to treat them, the collective health of our society would increase exponentially. We may never be able to cure certain diseases with our current approaches; until we refine our techniques so that viable cures can be discovered with approaches such as gene therapy, the “cure” lies in prevention, not treatment of disease. With natural, health-promoting agents in addition to a healthy diet and exercise program we can conceivably prevent diseases such as cancer, diabetes, and cardiovascular disease before they occur. You cannot have fitness without health, and green tea has been shown to increase fitness and health at the same time. With all of the proven benefits, there lacks any good reason not to include green tea as a supplement in your diet and nutrition program; 2-3 6-ounce servings per day should be sufficient to reap all of its benefits for health and fitness.