Green coffee bean extract (GCBE) contains chlorogenic acid — the compound destroyed by roasting — that was hyped as a "miracle weight loss" supplement after Dr. Oz's 2012 endorsement. The key study behind the hype (Vinson 2012) was RETRACTED due to data fabrication, and the manufacturer (Applied Food Sciences) paid $3.5 million to the FTC for false advertising. Our research shows chlorogenic acid does modestly reduce blood pressure (5 mmHg) and blood sugar, but the weight loss evidence is weak and tainted by fraud. This is the poster child for supplement industry overpromising.
Chlorogenic acid (CGA) — a polyphenol ester of caffeic acid and quinic acid — works through: (1) inhibition of glucose-6-phosphatase in the liver, reducing gluconeogenesis and hepatic glucose output; (2) inhibition of intestinal α-glucosidase, slowing carbohydrate digestion and glucose absorption; (3) NO-mediated vasodilation (similar to other polyphenols), lowering blood pressure; (4) AMPK activation, stimulating fatty acid oxidation. Roasting coffee at >200°C destroys 80-100% of CGA, which is why green (unroasted) beans are used. However, the fat-burning effects are modest at best — the dramatic results were fabricated.
No critical interactions identified.
Reviewed by the Scan Dose Research Team and Clinical Advisory Board | Last updated:
Not medical advice. Based on published clinical research and systematic reviews.