Green coffee beans are beans that have not been roasted. Green coffee beans contain chlorogenic acid which has been shown to slow the release of glucose into the body after a meal, thereby promoting weight loss. When coffee beans are roasted, the chlorogenic acid is lost. Hence the reason why coffee consumption has not shown the same weight loss benefits as green coffee bean extract.
Nine clinical studies evaluated green coffee bean's health benefits. A minimum 45 percent chlorogenic acid content was present in the green coffee bean extract used in the clinical research studies.