To study the effects of dietary stigmasterol on sterol and bile acids metabolism, Wistar rats were fed diets containing various amounts of stigmasterol. Feeding high stigmasterol doses (11, 26 or 52 mg/day) led to increased cholesterol, coprostanol and bile acid output. These effects were dose-dependent, and likely to be related to the inhibitory effect of plant sterols on cholesterol absorption. Moreover, it accounts for the beneficial effect of the stigmasterol on cholesterol lowering.