How many stereoisomers of cholesterol found in nature?

Cholesterol has a total of eight stereoisomers due to its four chiral centers. However, in nature, only one specific stereoisomer, known as (3β)-cholesterol, is predominantly found in biological systems. This is the biologically active form of cholesterol that plays a crucial role in cell membrane structure and function. Other stereoisomers may exist but are not typically found in significant amounts in nature.