The Skinny on Green Tea and Weight Loss

I’m asked all the time: “Will drinking Green tea or Oolong tea help me lose weight?” My answer has been: “There is some evidence that they can assist in the metabolism of fat in the body. I can say with certainty that if you stop eating and only drink tea, you will lose weight.”

Here is the more scientific version recently published by the British Journal of Nutrition, FirstView Articles. Copyright © The Authors 2011. DOI: 10.1017/S0007114511003849 (About DOI) Published online: 2011

“Tea has been consumed across the globe for centuries, comprising a significant proportion of the habitual diet of many far eastern countries. While its origins have been traced to China, it is now thought to be the second most consumed beverage in the world(1,2). It is manufactured from the leaf and bud of the plant Camellia sinensis, with the manufacturing process determining the type of tea produced, ranging from ‘fermented’ black and red teas, through ‘semi-fermented’ Oolong, to ‘non-fermented’ Green tea.

The black colour and bitter taste in black tea results from the oxidation of a group of chemicals termed ‘polyphenols’ (also known as catechins) by the enzyme polyphenol oxidase. This oxidative reaction is avoided in green tea where the drying and steaming processes employed inactivate this enzyme(1). Sparing these polyphenols is thought crucial to the many health benefits attributed to green tea over the centuries. A growing body of literature has emerged in the last three decades on an apparent plethora of benefits supposedly hidden in this relatively widespread and inexpensive beverage, included among which are anti-obesogenic(3), anti-diabetic(4), anti-carcinogenic(5), anti-bacterial(6) and anti-viral properties(7). In the present review I will concentrate on the first of these: the effects of green tea ingestion on energy expenditure (EE) and fat metabolism. In 1999, a paper was released demonstrating an apparent increase in EE in human subjects over 24 h, resulting from green tea administration(8). Publications such as this have since led pharmaceutical and nutraceutical manufacturers to rush to incorporate green tea extract (GTE) into ‘fat-stripping’ weight management pills and protein shakes aimed at gym goers, athletes and the general public. The value of such a discovery was immediately apparent, both medically and within the domain of sports nutrition and gym use, with sports and fitness magazines such as Men’s Health relaying this information to their readers(9). Were this property of a very cheap commodity verified, it would imply a lucrative market in weight management supplements.

In the present review I aim to evaluate the validity of the evidence which seeks to corroborate these ‘fat burning’ and anti-obesogenic properties of green tea, considering its potential applications, along with a synthesis of putative modes of action…”

Sip green tea. Feel happy… and skinny?

The Skinny on Green Tea and Weight Loss