The seeds of Trigonella foenum graecum (fenugreek) have been reported to have antidiabetic and hypocholesterolaemic properties in both animal models and humans. Activity has been attributed largely to fenugreek's saponin and high fibre content, and is probably not related to its major alkaloid trigonelline. Antihyperglycaemic effects have been linked to delayed gastric emptying caused by the fibre content, and to (unidentified) components that inhibit carbohydrate digestive enzymes. Fenugreek administration may increase plasma insulin levels in vivo. Its major free amino acid, 4-hydroxyisoleucine, stimulates insulin secretion from perfused pancreas in vitro. The hypocholesterolaemic effect has been attributed to increased conversion of hepatic cholesterol to bile salts due to loss, in the faeces, of complexes of these substances with fenugreek fibre and saponins. Fenugreek treatment selectively reduces the LDL and VLDL fractions of total cholesterol, and HDL-cholesterol has also been reported to increase in alloxaninduced diabetic rats and type II diabetic individuals following treatment with fenugreek. Fenugreek administration has not been reported to cause any toxicological effects. Its regular consumption may therefore be beneficial in the management of diabetes and the prevention of atherosclerosis and coronary heart disease.