[3] β-Sitosterol is being studied for its potential to reduce benign prostatic hyperplasia (BPH)[4][5] and blood cholesterol levels.

[6] While plant sterols are usually beneficial, there is a rare autosomal recessive genetic disorder phytosterolemia which causes over-absorption of phytosterols.

This led to suspicion that some athletes testing positive on boldenone undecylenate did not actually abuse the hormone itself but consumed food rich in β-sitosterol.

Extensive efforts on the part of many laboratories eventually led to the discovery of a pseudomonas microbe that efficiently effected that transformation.

Fermentation digests the entire aliphatic side-chain at carbon 17 to afford a mixture of 17-keto products including dehydroepiandrosterone.

The hydrogenation step of a previously proposed synthesis involved the catalyst Pd/C and the solvent ethyl acetate.

The last step of the synthesis is deprotection of the β-ring double bond of 5 with p-TsOH, aqueous dioxane, and heat (80 °C) to yield β-sitosterol 6.

An alternative pathway is described for phytosterol synthesis in some animals, a key enzyme responsible is the sterolmethyltransferase (SMT).