Green tea is a drink that is associated with weight loss in humans and animals. This weight loss is often attributed to the caffeine present in tea, and this may be a significant factor. However, green tea is also rich in catechin polyphenols and these may have significant weight loss effects. The evidence that catechins are able to cause weight loss comes from a number of randomised control studies as well as animal and cell culture models. One explanation for this weight loss effect is that green tea polyphenols are able to cause a stimulation of the sympathetic nervous system and this in turn can increase fat oxidation rates. Because caffeine also has this effect, the caffeine in green tea may act synergistically with the polyphenols to stimulate fat oxidation and increase energy expenditure. Another possibility is that green tea polyphenols can modify appetite and thus reduce energy intake or prevent the absorption of certain nutrients, particularly sugars. Green tea polyphenols may also be able to inhibit starch digesting and sugar digesting enzymes and thus delay carbohydrate absorption, or may allow the favourable growth of microflora that can have positive metabolic effects on the consumer through the synthesis of nutritive factors. Lastly, drinking green tea, which is mostly drunk without sugar, may reduce consumption of sugar, a known obesogenic factor.
Eat Well, Stay Healthy, Protect Yourself
RdB
