br In mice, raspberry ketone has been shown to prevent high-fat-diet-induced elevations in body weight when given in very high doses, up to 2 of body weight. However, in another study in rats, no effects on body weight were observed with doses up to 200 times greater than the estimated intake in humans. The high dose effect is reported to stem from the alteration of lipid metabolism, increasing norepinephrine-induced lipolysis.