Year after year weight loss tops the list of New Year's resolutions – and with good reason. The Centers for Disease Control and Prevention estimate that two out of every three U.S. adults are overweight or obese. If you're one of the millions of people struggling to lose weight, it may be time to add a little green tea to your diet.
There is a strong body of scientific evidence supporting the beneficial effects green tea can have on body weight, waist circumference and abdominal fat.
Tea is the most widely consumed beverage in the world, second only to water. Green tea in particular has gained great popularity in recent years, largely due to the tremendous amount of research showing its multiple health benefits. Much of that research has focused on the antioxidant properties found in green tea and their potential to reduce the risks of cardiovascular disease and cancer.
What is sometimes overlooked, however, is green tea's ability to promote weight loss and reduce body fat.
The History and Mythology of Green Tea
Archeologists have found that people in China and India ate tea leaves steeped in boiling water as far back as 5,000 years ago. Green tea has been used in traditional Chinese and Indian medicine for centuries as a stimulant, diuretic, and astringent (to control bleeding and help wounds heal), and to support heart health. Additional uses of green tea have historically included treating flatulence, regulating body temperature, regulating blood sugar, promoting digestion, and improving mental processes.
There is a popular legend in India concerning the origins of the tea plant. It is said that when Prince Siddhartha Gautama, the founder of Buddhism, was traveling through China, he became frustrated at his inability to stay awake during meditation so he tore off his eyelids. They say that a tea plant sprouted from the spot where his eyelids fell, and the plant gave him the ability to stay awake, meditate and reach enlightenment.
Currently about 500,000 tons of green tea are produced each year throughout Asia and in parts of the Middle East and Africa. It is mostly consumed by people in Asia, the United States, Europe and some parts of North Africa.
What Makes Green Tea Different?
There are three main varieties of tea - green, black and Oolong - that all come from the leaves of the Camellia sinensis plant. When tea leaves are ready to harvest, they contain very high concentrations of an important class of polyphenols called catechins. However, as tea leaves are allowed to ferment, the catechin levels decline. Partially fermented leaves turn into Oolong tea and fully fermented leaves become black tea.
By contrast, green tea is produced by heat-treating the leaves soon after harvest to prevent fermentation and preserve the natural catechins.
This process also preserves the green color of the leaves. Although there are six primary catechin compounds in green tea, epigallocatechin gallate (EGCG) is by far the most active, most abundant and most studied.
It is also EGCG that appears to be responsible for many of the weight loss benefits attributed to green tea.
Green Tea and Weight Loss – The Research
Multiple studies have been published showing that regular consumption of green tea - or of supplements containing the catechins extracted from green tea - may influence energy metabolism, body weight and body fat content.
Research into how the catechins, particularly EGCG, found in green tea benefit weight loss and fat distribution has been conducted in vitro (test tubes), using mice, and finally in clinical trials with humans.
All three research techniques have produced results indicating that high doses of catechins can be effective for:
• Promoting weight loss
• Reducing waist circumference
• Improving energy metabolism
• Decreasing intra-abdominal fat
• Supporting maintenance of lost weight.
Following are just a few of the clinical trials that demonstrate the positive weight loss benefits of green tea's catechins:
• In 2009, researchers in the Netherlands did a meta-analysis of 11 studies evaluating how the catechins found in green tea affect weight loss and weight management. According to their findings, “Catechins significantly decreased body weight and significantly maintained body weight after a period of weight loss.”(1)
• A randomized placebo-controlled trial in China studied the effects of catechins on weight and body composition. A total of 182 moderately overweight men and women were divided into four groups and given two beverage servings a day for 90 days. The beverage given to the control group contained almost no catechins while the other groups received catechin doses ranging from 458 mg/day to 886 mg twice a day. In their conclusions, the researchers said, “This investigation shows that regular consumption of a very-high catechin green tea [500-900 mg] over 90 days leads to significant reductions in measures such as body weight, waist circumference and intra-abdominal fat...”(2)
• Scientists know that in vitro, green tea extract inhibits gastric and pancreatic lipases (enzymes that break down fat) and stimulates thermogenesis (the fat-burning process). Based on these principles, an open-label trial was conducted to study the effects of green tea extract with EGCG on moderately obese patients. After three months, the subjects' body weight decreased by 4.6% and waist circumference decreased by 4.5%.(3)
• Based on data from previous human studies indicating that green tea extracts may support body weight reduction by increasing thermogenesis and fat oxidation, a German study looked specifically at the effects of EGCG on weight loss. They found that EGCG "has the potential to increase fat oxidation in men and may thereby contribute to the anti-obesity effects of green tea."(4)
To Drink or To Supplement...
Is it better to drink your green tea or to take a green tea extract supplement? While drinking green tea is certainly good for you, there are a couple of reasons why supplementing with an EGCG-rich green tea extract is better:
• Convenience. In order to get the amount of EGCG and other catechins used in research and found to be effective for weight loss, you would have to drink about 10 cups of green tea a day, depending on the strength of the brew. Or you could take a single capsule of ProHealth's Green Tea EGCG Extreme.
• 99.6% caffeine free. Even if you could manage to drink the needed 10 cups a day or more of green tea, you would be getting a great deal of caffeine with it. ProHealth's Green Tea EGCG Extreme supplement contains only a trace amount of caffeine.
ProHealth's Green Tea EGCG Extreme is the most potent green tea extract on the market today.
Each veggie capsule of Green Tea EGCG Extreme provides 455 mg of catechins, 390 mg of which are EGCG. One to two capsules each day provides catechin levels comparable to those used in clinical trials and found to be effective for weight loss. Green Tea EGCG Extreme may be taken with or without food.
In Summary
Green tea has been studied extensively in humans, animals and laboratory tests. In addition to its many other known health benefits, green tea contains powerful catechins that have been shown to promote weight loss and reduce body fat, particularly in the abdominal area.
* Supplement research reporter Karen Lee Richards is Lead Expert specializing in Fibromyalgia and ME/CFS for HealthCentral’s chronic pain site (www.HealthCentral.com/chronic-pain)
References:
1. Hursel R, et al."The effects of green tea on weight loss and weight maintenance: a meta-analysis" Int J Obes (Lond). 2009 Sep;33(9):956-61.
2. Wang H, et al. (Full Text) "Effects of catechin enriched green tea on body composition" Obesity (Silver Spring). 2010 Apr;18(4):773-9.
3. Chantre P, Lairon D. "Recent findings of green tea extract AR25 (Exolise) and its activity for the treatment of obesity" Phytomedicine. 2002 Jan;9(1):3-8.
4. Boschmann M, Thielecke F. (Full Text) "The effects of epigallocatechin-3-gallate on thermogenesis and fat oxidation in obese men: a pilot study" J Am Coll Nutr. 2007 Aug;26(4):389S-395S.
Note: This information has not been evaluated by the FDA. It is general information and is not intended to prevent, diagnose, treat or cure any illness, condition or disease. It is very important that you make no change in your healthcare plan or health support regimen without researching and discussing it in collaboration with your professional healthcare team.
