Alternate Title

  • Sitosterol

Related Terms

  • 22,23-dihydrostigmasterol, 24-beta-ethyl-delta-5-cholesten-3beta-ol, 24-ethyl-cholesterol, 3-beta-stigmast-5-en-3-ol, (3beta)-stigmast-5-en-3-ol, a-dihydrofucosterol, alpha-dihydrofucosterol, alpha-phytosterol, a-phytosterol, Azuprostat®, beta sitosterin, beta sitosterol, beta-sitosterin, betasitosterol, beta-sitosterol glucoside, beta-sitosterol glycoside, B-sitosterol 3-B-D-glucoside, B-sitosterolin, cinchol, cupreol, delta-5-stigmasten-3beta-ol, phytosterols, plant sterols, quebrachol, rhamnol, sitosterin, sitosterin delalande, sitosterol, sitosterolins, sitosterols, sterinol, sterolins.
  • Combination product examples: Hazrol® (beta-sitosterol and beta-sitosterol glucoside), Moducare® (beta-sitosterol and beta-sitosterol glucoside), WA184 (beta-sitosteryl beta-D-glucoside).


  • Beta-sitosterol is one of the most common dietary phytosterols (plant sterols) found in and made exclusively by plants. Beta-sitosterol glucoside is a glucoside attached to beta-sitosterol. Other phytosterols include campesterol and stigmasterol. Stanols are saturated derivatives of sterols.
  • Beta-sitosterol is classified as a noncholesterol sterol, or neutral sterol. However, it is structurally similar to cholesterol, and it is the main sterol in the Western diet. Some evidence suggests that Americans consume about 165 milligrams of beta-sitosterol daily. Beta-sitosterol and beta-sitosterol glucoside are found in the tissue, plasma, and feces of healthy individuals. The average content of plant sterols found in the plasma of healthy Western individuals is one milligram per deciliter.
  • Beta-sitosterol is found in plant-based foods, such as fruits, vegetables, soybeans, breads, peanuts, and peanut products. Beta-sitosterol is also present in bourbon and oils, such as olive, flaxseed, and tuna. Plant oils contain the highest concentration of phytosterols. Nuts and seeds contain moderate amounts of phytosterols, while fruits and vegetables generally contain the lowest phytosterol concentrations. For example, roasted peanuts contain 61-114 milligrams per 100 grams, 78-83% of which is in the form of beta-sitosterol. Peanut butter contains 144-157 milligrams per 100 grams. These values indicate that peanut products are a good source of phytosterols, specifically, beta-sitosterol. Avocados have also been identified as a good source of beta-sitosterol. Beta-sitosterol can also be derived from pulp and paper mill effluents.
  • Margarines enriched with phytosterol esters, including beta-sitosterol, have been marketed for their cholesterol-lowering effects. Sitosterols are also used in products for the treatment of other medical conditions, including, but not limited to, benign prostatic hyperplasia (BPH) and immune stimulation.

Evidence Table


    These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

    High cholesterol

    Many studies have demonstrated that beta-sitosterol helps lower total cholesterol and low-density lipoprotein (LDL, or “bad”) cholesterol.

    Benign prostatic hypertrophy (BPH)

    Beta-sitosterol and beta-sitosterol glucoside have been used to treat symptoms of BPH (enlarged prostate). Several studies support this use, although the potential mechanism of action is unclear.

    Androgenetic alopecia (treatment)

    It is unclear if beta-sitosterol helps treat androgenetic alopecia, also called male-pattern baldness.


    Due to the potential immune-boosting effects of beta-sitosterol and beta-sitosterol glucoside, they have been studied as a treatment for HIV. However, more research is needed before a conclusion can be made.

    Immune suppression

    Beta-sitosterol and beta-sitosterol glucoside have been used to minimize immunosuppressant responses after intense exercise. More research is needed to determine if this use is effective.

    Rheumatoid arthritis

    Beta-sitosterol and beta-sitosterol glucoside may help lower blood levels of the inflammatory marker, interleukin-6 (IL-6). However, it is unclear if supplementation would be beneficial for rheumatoid arthritis.

    Tuberculosis (adjunct treatment)

    Beta-sitosterol and beta-sitosterol glucoside have been studied for the treatment of tuberculosis in combination with antituberculosis medications. Larger populations of patients with tuberculosis should be evaluated in future studies before a conclusion can be made.

*Key to grades:



    The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.



    The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

  • Adults (18 years and older)

    • Twenty milligrams of beta-sitosterol and 0.2 milligrams of beta-sitosterol glucoside have been taken three times daily for HIV, postmarathon immunosuppression, rheumatoid arthritis, and benign prostatic hypertrophy (BPH).
    • Margarine and salad dressings enriched with phytosterol esters have been shown to reduce total cholesterol and low-density lipoprotein (LDL) cholesterol (also called “bad cholesterol”), when consumed daily as 1.6-9 grams of phytosterols. Also, 1.5-2 grams of sitostanol, a hydrogenated derivative of sitosterol, has been used daily.
  • Children (under 18 years old)

    • For high cholesterol, children six years of age have taken 1.5 grams of plant stanols daily. Also, 1.2 grams of plant sterols has been taken daily in children 7-13 years old, and 2.3 grams of plant sterols has been taken daily in children 5-12 years old.



    The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

  • Allergies

    • Avoid in individuals with known allergy to beta-sitosterol or beta-sitosterol glucoside.
    • Some brands of sitosterol are made from a natural pine source and therefore may have possible cross-sensitivity in people allergic to pine.
  • Side Effects and Warnings

    • Beta-sitosterol is likely safe when taken by mouth in recommended doses for up to six months.
    • Beta-sitosterol may lower blood sugar levels. Caution is advised in patients with diabetes or low blood sugar levels and in those taking drugs, herbs, or supplements that affect blood sugar. Blood glucose levels may need to be monitored by a qualified healthcare professional, including a pharmacist. Medication adjustments may be necessary.
    • Beta-sitosterol may increase the risk of bleeding. Caution is advised in patients with bleeding disorders or those taking drugs that may increase the risk of bleeding. Dosing adjustments may be necessary.
    • Other reported side effects include asthma and difficulty breathing, constipation, diarrhea, nausea, erectile dysfunction, and decreased libido. In animals, plant sterols may have estrogen-like effects. The combination of beta-sitosterol and beta-sitosterol glucoside may promote weight gain.
    • Use cautiously in individuals with asthma or other respiratory diseases.
    • Use cautiously in patients with primary biliary cirrhosis, ileostomy, gallstones, neurodegenerative disorders, diverticular disease, short bowel syndrome, and celiac disease.
    • Sitosterolemia, also known as phytosterolemia, is a rare disease that causes people to absorb excessive amounts of plant sterols. Patients with this condition have an increased risk of coronary artery disease (CAD). They may also have lipid-filled nodules (called xanthomas) in the skin and tendons. Sitosterolemia is treated with cholestyramine and a low-plant sterol diet.
  • Pregnancy and Breastfeeding

    • Taking beta-sitosterol in medicinal amounts is not recommended during pregnancy or breastfeeding, due to a lack of scientific data.



    Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.

  • Interactions with Drugs

    • Acarbose may increase the absorption of beta-sitosterol.
    • Beta-sitosterol may protect and improve the absorption of acid-labile antibiotics.
    • Activated charcoal may slightly decrease blood levels of beta-sitosterol.
    • Beta-sitosterol may have blood sugar-lowering effects and interact with antidiabetic agents.
    • Beta-sitosterol may increase the effects of cholesterol-lowering drugs. Lifibrol, a cholesterol-lowering drug, has been shown to reduce sterols, including lanosterol, lathosterol, beta-sitosterol, and campesterol.
    • Beta-sitosterol may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants (blood thinners) such as warfarin (Coumadin®) or heparin, antiplatelet drugs such as clopidogrel (Plavix®), and nonsteroidal anti-inflammatory drugs such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®).
    • Beta-sitosterol and beta-sitosterol glucoside may improve weight gain and increase white blood cell counts when used in combination with various antituberculosis agents.
    • Cholestyramine and ezetimibe have been shown to reduce beta-sitosterol concentrations in patients with sitosterolemia.
    • In theory, beta-sitosterol may interact with cyclooxygenase inhibitors.
    • Taking beta-sitosterol plus diosgenin may affect the uptake of diosgenin by the liver.
    • Sterols may increase the effects of finasteride and alpha-blockers.
    • High-lipase pancreatin may alter fecal excretion of beta-sitosterol.
    • Beta-sitosterol has demonstrated estrogenic and antiestrogenic activity and may interact with hormone replacement therapies.
    • NMDA receptor antagonists may block the neurotoxic actions of sterol glucosides.
  • Interactions with Herbs and Dietary Supplements

    • The absorption of vitamin E (alpha-tocopherol) may be decreased when taken with beta-sitosterol.
    • Activated charcoal may slightly decrease blood levels of beta-sitosterol.
    • Beta-sitosterol may have blood sugar-lowering effects and interact with antidiabetic herbs or supplements.
    • Beta-sitosterol may increase the effects of cholesterol-lowering agents. In theory, beta-sitosterol may increase the effects of beta-lactoglobulin tryptic hydrolysate (LTH).
    • Beta-sitosterol may increase the risk of bleeding when taken with herbs or supplements that increase the risk of bleeding.
    • Beta-sitosterol may reduce beta-carotene, lutein, and lycopene blood levels.
    • The fat substitute olestra has been to decrease the amount of beta-sitosterol in stools.
    • Beta-sitosterol does not appear to affect blood levels of vitamins A or D.


  • This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration ().



    Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to . Selected references are listed below.

  • Berges, R. R., Kassen, A., and Senge, T. Treatment of symptomatic benign prostatic hyperplasia with beta-sitosterol: an 18-month follow-up. BJU.Int. 2000;85(7):842-846.
    View Abstract
  • Bouic, P. J., Clark, A., Brittle, W., Lamprecht, J. H., Freestone, M., and Liebenberg, R. W. Plant sterol/sterolin supplement use in a cohort of South African HIV-infected patients–effects on immunological and virological surrogate markers. S.Afr.Med.J 2001;91(10):848-850.
    View Abstract
  • Bouic, P. J. and Lamprecht, J. H. Plant sterols and sterolins: a review of their immune-modulating properties. Altern.Med.Rev. 1999;4(3):170-177.
    View Abstract
  • Charest, A., Desroches, S., Vanstone, C. A., Jones, P. J., and Lamarche, B. Unesterified plant sterols and stanols do not affect LDL electrophoretic characteristics in hypercholesterolemic subjects. J.Nutr. 2004;134(3):592-595.
    View Abstract
  • Davidson, M. H., Maki, K. C., Umporowicz, D. M., Ingram, K. A., Dicklin, M. R., Schaefer, E., Lane, R. W., McNamara, J. R., Ribaya-Mercado, J. D., Perrone, G., Robins, S. J., and Franke, W. C. Safety and tolerability of esterified phytosterols administered in reduced-fat spread and salad dressing to healthy adult men and women. J Am Coll.Nutr. 2001;20(4):307-319.
    View Abstract
  • Devaraj, S., Jialal, I., and Vega-Lopez, S. Plant sterol-fortified orange juice effectively lowers cholesterol levels in mildly hypercholesterolemic healthy individuals. Arterioscler.Thromb.Vasc.Biol. 2004;24(3):e25-e28.
    View Abstract
  • Klippel, K. F., Hiltl, D. M., and Schipp, B. A multicentric, placebo-controlled, double-blind clinical trial of beta-sitosterol (phytosterol) for the treatment of benign prostatic hyperplasia. German BPH-Phyto Study group. Br.J Urol. 1997;80(3):427-432.
    View Abstract
  • Lau, H. L., Puah, C. W., Choo, Y. M., Ma, A. N., and Chuah, C. H. Simultaneous quantification of free fatty acids, free sterols, squalene, and acylglycerol molecular species in palm oil by high-temperature gas chromatography–flame ionization detection. Lipids 2005;40(5):523-528.
    View Abstract
  • Natural Standard: The Authority on Integrative Medicine.
  • Nigon, F., Serfaty-Lacrosniere, C., Beucler, I., Chauvois, D., Neveu, C., Giral, P., Chapman, M. J., and Bruckert, E. Plant sterol-enriched margarine lowers plasma LDL in hyperlipidemic subjects with low cholesterol intake: effect of fibrate treatment. Clin.Chem Lab Med. 2001;39(7):634-640.
    View Abstract
  • Prager, N., Bickett, K., French, N., and Marcovici, G. A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of 5-alpha-reductase in the treatment of androgenetic alopecia. J Altern.Complement Med. 2002;8(2):143-152.
    View Abstract
  • Tammi, A., Ronnemaa, T., Gylling, H., Rask-Nissila, L., Viikari, J., Tuominen, J., Pulkki, K., and Simell, O. Plant stanol ester margarine lowers serum total and low-density lipoprotein cholesterol concentrations of healthy children: the STRIP project. Special Turku Coronary Risk Factors Intervention Project. J Pediatr. 2000;136(4):503-510.
    View Abstract
  • Thomsen, A. B., Hansen, H. B., Christiansen, C., Green, H., and Berger, A. Effect of free plant sterols in low-fat milk on serum lipid profile in hypercholesterolemic subjects. Eur.J.Clin.Nutr. 2004;58(6):860-870.
    View Abstract
  • Varady, K. A., Ebine, N., Vanstone, C. A., Parsons, W. E., and Jones, P. J. Plant sterols and endurance training combine to favorably alter plasma lipid profiles in previously sedentary hypercholesterolemic adults after 8 wk. Am.J.Clin.Nutr. 2004;80(5):1159-1166.
    View Abstract
  • Weststrate, J. A. and Meijer, G. W. Plant sterol-enriched margarines and reduction of plasma total- and LDL-cholesterol concentrations in normocholesterolaemic and mildly hypercholesterolaemic subjects. Eur.J Clin.Nutr. 1998;52(5):334-343.
    View Abstract