Green tea has been touted as a natural health enhancement to promote weight loss and longevity. My common mental image of the effects of green tea are of a peaceful person over the age of 100 who is slender, graceful, and agile. Is that way of being a result of green tea consumption? Maybe! And what is it about green tea that is so beneficial to our health? The primary component researchers have identified is epigallocatechin gallate, or EGCG. EGCG is one of the major polyphenol components in green tea. It is a powerful antioxidant that also has thermogenic properties, which helps increase metabolic activity.6 The polyphenol antioxidants in EGCG also support brain and heart health, and may also be anti-cancer.8 This article will discuss the properties of this supplement, and how incorporating it into your diet may be beneficial.
How Does it Work?
EGCG is a “polyphenol” with “antioxidant” and “thermogenic” properties. What does that even mean?! A polyphenol is a long chain of aromatic organic compounds, which is the most basic chemical description. More complex discussion around polyphenols is outside the scope of this article, but here’s a link to the Wikipedia article about them if you are interested in some dense reading. Antioxidants are substances that reduce the production of “free radicals,” which you have probably heard of. Basically, antioxidants reduce the chemical reactions in the body that can lead to cell damage.7
Thermogenesis is the process of creating heat. In humans, this occurs by increasing metabolism (burning calories) to produce such heat. The factors that induce thermogenesis are exercise, diet, and environmental temperature. When these factors are at play, the body increases the number of calories it burns to meet the demands of activity within its environment. Increasing caloric expenditure is fundamental to weight loss, a common goal in today’s society. By burning more calories, the body uses its energy that is stored in the form of fat and glycogen (carbs).
So, where does EGCG fit in to this? The catechins (another term for green tea’s polyphenols) and caffeine in EGCG promote thermogenesis and increased fat oxidation.2,3 This means that the body not only increases caloric expenditure, but also more readily utilizes fat in metabolism over glycogen and protein. EGCG components also act as blood thinners, neurogenesis stimulants1, and (possibly) tumor-growth inhibitors. Below is a summary of the potential health benefits of EGCG.
If used appropriately, it is possible that EGCG can have these health benefits:
- Weight Loss: Research has shown that those who consume EGCG throughout the day report higher energy expenditure than those who don’t. This is caused by an increase in fat oxidation and/or thermogenesis.2,3
- Heart Health*: Catechins have been known to improve blood flow and lower cholesterol. They may also be linked to blood-sugar maintenance.4,5
- Brain Health: Research has shown that EGCG promotes neurogenesis (growth of nerve tissue) in the hippocampus, leading to improved cognitive function.1
- Anti-Cancer*: EGCG has potential to have powerful antioxidant effects on free radicals, and is thought to promote healthy cell growth and may destroy cancer cells.4,5
*more research needs to be done in these areas
EGCG can be consumed in pill form or by drinking green tea. Normal dosing is between 350-700mg/day and varies based on body type and personal goals.9 If you decide to take capsules of EGCG, they should be taken with food. ALWAYS read the label and instructions on any supplements you purchase. If you prefer to drink tea, about 3 cups of green tea will provide 240-320mg of EGCG.
A common misconception is that natural substances can be overconsumed without detrimental effects. THIS IS NOT TRUE! It is possible for natural supplements to interact poorly with pharmacological medications, and to overdose on natural substances. Too much EGCG can lead to mild to serious side effects, including8:
- Sleep problems
- Irregular heartbeat
- Ringing in the ears
A healthcare provider should be consulted if you are pregnant, may become pregnant, breastfeeding, have a history of blood coagulation disorders, liver dysfunction, or are taking any prescription drug(s).8
As stated above, EGCG has been found to have a multitude of benefits on overall health and can contribute to a healthy lifestyle Based on the research, it can promote thermogenesis and fat oxidation for athletes during workouts. EGCG should not be taken as a primary means of weight loss or treatment for serious diseases involving the heart, brain, or cancer. A doctor or dietician should be consulted before adding any supplement and can assign proper dosing.
So, what does this mean for you? EGCG in green tea may be beneficial to your health, and it’s nothing to hang your hat on. Combined with a complete diet and exercise, positive effects are more likely to be seen. And if you enjoy green tea, keep on enjoying it!
For more information on the health benefits of EGCG, try these websites:
- Bai, Y., Y. Wang, M. Li, X. Xu, M. Song, and H. Tao. “Green Tea Epigallocatechin-3-gallate (EGCG) Promotes Neural Progenitor Cell Proliferation and Sonic Hedgehog Pathway Activation during Adult Hippocampal Neurogenesis.” NCBI. U.S. National Library of Medicine, 12 Aug. 2012. Web. 21 Oct. 2013.
- Dulloo, A. G., J. Seydoux, L. Girardier, P. Chantre, and J. Vandermander. “Green Tea and Thermogenesis: Interactions between Catechin-polyphenols, Caffeine and Sympathetic Activity.” International Journal of Obesity2 (2000): 252-58. Nature.com. Nature Publishing Group. Web. 21 Oct. 2013.
- Dulloo, Abdul G., Claudette Duret, Dorothee Rohrer, Lucien Girardier, Nouri Mensi, Marc Fathi, Philippe Chantre, and Jacques Vandermander. “Efficacy of a Green Tea Extract Rich in Catechin Polyphenols and Caffeine in Increasing 24-h Energy Expenditure and Fat Oxidation in Humans.” The American Journal of Clinical Nutrition6 (1999): 1040-045. The American Journal of Clinical Nutrition. The American Society for Nutrition. Web. 21 Oct. 2013.
- “Green Tea.” The World’s Healthiest Foods. The George Mateljan Foundation, 21 Oct. 2012. Web. 21 Oct. 2013.
- “Green Tea.” WebMD. WebMD, LLC, n.d. Web. 21 Oct. 2013.
- Martinac, Paula. “What Is EGCG in Green Tea?” Healthy Eating. Hearst Communications Inc., n.d. Web. 21 Oct. 2013.
- “Phytochemicals.” Phytochemicals. American Cancer Society, Inc., 17 Jan. 2013. Web. 21 Oct. 2013.
- Scott, Paula S. “Health Benefits of Green Tea.” WebMD. Ed. David Kiefer, MD. WebMD, LLC, n.d. Web. 21 Oct. 2013.
- “Source Naturals: EGCG.” Source Naturals. Source Naturals, n.d. Web. 21 Oct. 2013.