Many foods naturally contain beta-sitosterol, but it is also available for purchase at retailers such as GNC, explains About.com. Beta-sitosterol is a type of phytosterol, a compound similar to cholesterol, and it may offer a number of medical benefits.
Supplement companies sell beta-sitosterol as a natural remedy for a number of conditions such as allergies, asthma, chronic fatigue syndrome and bronchitis, explains About.com. It also treats cold and flu symptoms, fibromyalgia, high cholesterol, menopausal symptoms, and arthritis. As of 2015, there is also evidence that beta-sitosterol can help treat an enlarged prostate in men over the age of 40, and it provides relief for symptoms such as bladder and urination issues.
There is also evidence that beta-sitosterol can treat certain types of cancer, such as colon and breast cancer, claims About.com. Even if beta-sitosterol is not totally effective on its own, research shows that in the case of breast cancer, the supplement can improve the way cancer drugs work.
Although experts consider beta-sitosterol to be safe for up to six months at a time, some should not take this supplement, reports About.com. People with gallstones, diabetes or Alzheimer's disease should avoid taking this supplement before talking to a doctor. People take other medications and women who are pregnant or nursing should also avoid taking beta-sitosterol.