Time-release pregnenolone (plant source) for superior utilization. In the body, pregnenolone is metabolized from cholesterol by the cytochrome P450 enzyme. It serves as a parent hormone for all adrenal cortical steroids, including progesterone, testosterone, dehydroepiandrosterone, dihydrotestosterone, aldosterone, cortisol and estradiol. Pregnenolone levels decrease with age, during periods of fatigue, or in conditions of inadequate cholesterol production.