Simmondsin, 2-(cyanomethylene)-3 hydroxy 4,5 dimethoxy cyclohexyl beta-D-glucoside, from jojoba meal reduces food intake in rats. We investigated the mechanism of action simmondsin, by studying the effects of fasting or of vagotomy on the food intake reduction. The food intake reduction was significantly less in fasted rats than in non-fasted rats. The reduction of food intake was also significantly diminished after vagotomy. The results of the present experiments suggest that simmondsin reduces intake of food in rats through the augmentation of satiety, in part vagally mediated.