A variety of steroid hormones are produced from cholesterol by oxidation of the side chain at C-17 of sterols.

The major group of steroid hormones are the male and female sex hormones of the adrenal cortex, cortisol and aldosterone.

All of those hormones contain an intact steroid nucleus. They are produced in one tissue and carried in the bloodstream to target tissues, where they bind to highly specific receptor proteins and trigger changes in gene expression and metabolism. Because of the very high affinity of the receptor for hormone, very low concentrations of hormone suffice to produce the effect on target tissues.