Beta-sitosterol is one of a group of organic compounds found in plants that, alone and in
combination with similar plant sterols, reduces blood levels of cholesterol.1 2 3
Where is it found?
Beta-sitosterol is one of several plant sterols (cholesterol is the main animal sterol)
found in almost all plants. High levels are found in rice bran, wheat germ, corn oil, and soybeans.
Peanuts and its products, such as peanut
oil, peanut butter, and peanut flour, are
good sources of plant sterols, particularly beta-sitosterol.4
Beta-sitosterol has been
used in connection with the following conditions (refer to the
individual health concern for complete information):
Who is likely to be deficient?
Because beta-sitosterol is not an essential nutrient, deficiencies do not occur.
How much is usually taken?
Between 500 mg and 10 grams of beta-sitosterol per day have been used in clinical research
to reduce elevated blood cholesterol levels.
Between 60 (20 mg three times per day) and 130 mg per day have been used in trials reporting a
reduction in prostatic hyperplasia-related
symptoms.5 6
Are there any side effects or interactions?
Ingesting plant sterols interferes with
beta-carotene and vitamin E absorption,
resulting in lower blood levels of these nutrients.7
At the time of writing, there were no well-known drug interactions
with beta-sitosterol.
References:1. Lees AM, Mok HYI, Lee RS, et al. Plant sterols as cholesterol-lowering
agents: clinical trials in patients with hypercholesterolemia and studies of sterol balance.
Atherosclerosis 1977;28:325-38.
2. Pelletier X, Belbraouet S, Mirabel D, et al. A diet moderately
enriched in phytosterols lowers plasma cholesterol concentrations in normocholesterolemic
humans. Ann Nutr Metab 1995;39:291-5.
3. Jones PJ, Raeini-Sarjaz M, Ntanios FY, et al. Modulation of plasma
lipid levels and cholesterol kinetics by phytosterol versus phytostanol esters. J Lipid
Res 2000;41:697-705.
4. Awad AB, Chan KC, Downie AC, Fink CS. Peanuts as a source of
ß-sitosterol, a sterol with anticancer properties. Nutr Cancer
2000;36:238–41.
5. Berges RR, Windeler J, Trampisch HJ, et al. Randomised,
placebo-controlled, double-blind clinical trial of beta-sitosterol in patients with benign
prostatic hyperplasia. Lancet 1995;345:1529–32.
6. Klippel KF, Hiltl DM, Schipp B. A multicentric, placebo-controlled,
double-blind clinical trial of ß-sitosterol (phytosterol) for the treatment of benign
prostatic hyperplasia. Br J Urol 1997;80:427–32.
7. Richelle M, Enslen M, Hager C, et al. Both free and esterified plant
sterols reduce cholesterol absorption and the bioavailability of beta-carotene and
alpha-tocopherol in normocholesterolemic humans. Am J Clin Nutr
2004;80:171–7.