3-?Dehydrotrametenolic acid, isolated from the sclerotium of Poria cocos, is a lactate dehydrogenase (LDH) inhibitor. 3-?Dehydrotrametenolic acid promotes adipocyte differentiation in vitro and acts as an insulin sensitizer in vivo. 3-?Dehydrotrametenolic acid induces apoptosis and has anticancer activity.