Organic Health Zone Green Coffee extract contains Chlorogenic Acid (GCA). GCA is the main constituent of green coffee that has been shown to boost metabolism. Our product features concentrated Green Coffee Bean extract with less caffeine (equivalent to 1/10 of a cup of coffee) and no added artificial ingredients. With our Green Coffee Bean Extract you get both the quality and quantity of chlorogenic acid per serving on a daily basis. How Does It Work? The key ingredient is called chlorogenic acid. Chlorogenic acid has been clinically proven to slow the release of sugar into the bloodstream, while simultaneously boosting your metabolism and burning unhealthy cell in the liver. These two mechanisms work together to inhibit the formation of unhealthy cells. Green coffee extract contains 20mg of caffeine per serving, in contrast, an 8oz cup of coffee has approximately 180mg of caffeine per serving.