Sterols & Steroids

Phytosterols are near-universal; the more specialized steroids are concentrated in particular plants:

The phytosterols' best-established effect is competitive: because they resemble cholesterol, they crowd it out of intestinal micelles and reduce its absorption. That is a genuine, dose-dependent LDL-lowering effect and the basis of sterol-fortified foods. Beta-sitosterol also has reasonable trial evidence in benign prostatic hyperplasia.

The withanolides are the actives credited with ashwagandha's adaptogenic and anti-inflammatory profile, with withaferin A the potent, more cytotoxic member and withanolide A the neurotrophic one.

Diosgenin is the industrial feedstock from which progesterone and cortisone were first synthesized — in a chemical plant, over several deliberate steps. The human body cannot perform that conversion.

Wild yam creams and capsules are therefore not a source of progesterone or DHEA, whatever the label implies. It is the single most repeated error about this compound class and worth checking any product claim against.