Hoodia’s appetite suppressant effect is based on experiments in rats. Human trials have not been conducted.
Hoodia gordonii is a cactus found in the Kalahari desert and in Namibia. The local tribesmen consume Hoodia to survive long periods of starvation. Supplements containing Hoodia are being promoted for weight loss and some cancer patients use them for weight control. But there are no clinical data to support this use.
The FDA has warned the manufacturer and distributors of a Hoodia product against making unsubstantiated and misleading claims about weight loss.
Hoodia gordonii is a cactus prevalent in southeastern Africa. The local tribesmen are known to consume Hoodia to ease hunger during periods of starvation. A compound isolated from Hoodia was shown to reduce food intake in rats (1). However, consumption of a hoodia extract did not affect body weight in healthy overweight women (7).
Currently, supplements containing Hoodia are being promoted for weight loss and some cancer patients use these for weight control. Patients should use caution as hoodia can interact with certain prescription drugs. The FDA has warned the manufacturer and distributors of a Hoodia product against making unsubstantiated and misleading claims about weight loss (2).
Hoodia extracts are thought to have an appetite suppressant effect, but it is not clear what causes such an effect. In an experiment done in rats, intracerebroventricular administration of P57 resulted in an increase in ATP level in hypothalamic neurons. It is hypothesized that neurons in the basal hypothalamus may be sensitive to changes in ATP levels and thereby, regulate food intake (1). P57 also inhibited CYP 3A4 activity (5)(6).
In another study, pregnane glycosides specifically suppressed steroidogenesis by strongly inhibiting 11β-hydroxylase and steroid 17-alpha-monooxygenase, and weak inhibition of cytochrome P450 side chain cleavage enzyme and 21 Beta-hydroxylase (9).