Supplements Dietary Supplements What You Should Know About Beta Sitosterol Plant-Based Compound May Reduce Your Risk of Heart Disease By Brittany Lubeck, MS, RDN Updated on March 04, 2024 Medically reviewed by Beth Thomas, PharmD Print Table of Contents View All Table of Contents Uses Side Effects Precautions Dosage What Happens If I Take Too Much? Interactions Similar Supplements Sources FAQ Beta-sitosterol is one of several plant-based substances known as phytosterols. It is similar in chemical structure to the cholesterol your body makes. Naturally found in plants, beta-sitosterol can be consumed through food sources such as vegetable oils, nuts, seeds, and legumes. It is also available in supplement form and a lipid emulsion. Beta-sitosterol is sometimes used to reduce high cholesterol. It has also been studied for a host of other health conditions. This article will review its potential uses, side effects, dosage, and more. This article will discuss the potential benefits and uses of beta-sitosterol, plus what you should know about its side effects, precautions, and how to get it in food and supplement forms. Verywell / Anastasia Tretiak Uses of Beta-Sitosterol Supplement use should be individualized and vetted by a healthcare professional, such as a registered dietitian, pharmacist, or healthcare provider. No supplement is intended to treat, cure, or prevent diseases. Research has shown that phytosterols, including beta-sitosterol, can play a role in helping certain medical conditions. However, many studies on beta-sitosterol have been animal studies. Although we can often learn from animal studies, we cannot definitively say that the results in animals will be the same in humans. Despite this, there is some interesting research involving beta-sitosterol and various health concerns that we will look at next. May Reduce Cholesterol A review from 2016 looked at numerous studies on beta-sitosterol and its potential role in reducing cholesterol. Researchers found that beta-sitosterol can reduce the amount of LDL "bad" cholesterol absorbed by your body. Because beta-sitosterol and cholesterol have similar structures, your body will choose to absorb beta-sitosterol and excrete cholesterol instead. The beta-sitosterol eaten from plants competes with cholesterol for absorption in your intestines. Over time, this can reduce the risk of atherosclerosis or hyperlipidemia, which can lead to heart disease. In short, phytosterols like beta-sitosterol are thought to reduce your risk of heart disease. The FDA has approved the claim that phytosterols (including beta-sitosterol) in the diet can reduce your risk of heart disease. However, anything less than 1.3 grams (g) per day of phytosterols does not lower your heart disease risk. May Improve Benign Prostatic Hyperplasia Beta-sitosterol may aid in the treatment of an enlarged prostate. This condition is also known as benign prostatic hyperplasia (BPH) and can block the flow of urine. Though research is dated, beta-sitosterol has been linked to improved symptoms in males (sex assigned at birth) with BPH. A systemic review of studies totaling 519 males with BPH found that beta-sitosterol improved urinary symptoms. It's not known exactly how beta-sitosterol improves BPH, but it is thought that it works by reducing inflammation in the prostate. A new study or review on this subject is needed to provide an update on the use of beta-sitosterol for BPH. Beta-sitosterol cannot directly treat BPH on its own. Traditional drugs used to treat this condition can help treat decreased or hesitant urinary flow. May Have Anti-cancer Properties Advocates of beta-sitosterol claim that it may have anti-cancer properties. However, most evidence supporting these claims is based on test tube studies (also called in vitro), which we can learn from but not use as strong evidence. A trial from 2010 that used both in vitro and in vivo models found that beta-sitosterol made from tropical milkweed (Asclepias curassavica) slowed the growth of human colon cancer cells. The in vivo models of the study included male rats. Similarly, a 2003 study found that beta-sitosterol induced apoptosis, or cell death, in breast cancer cells. Apoptosis is key to stopping the spread of cancer cells. But, again, this research was done in a test tube rather than on humans. None of this should suggest that beta-sitosterol can directly impact cancer cells. You should always follow the treatment plan prescribed by your healthcare provider for any medical condition. May Help Reduce Blood Sugar Although human trials are lacking, there is evidence from animal studies that beta-sitosterol could positively affect diabetes. In one study on rats, beta-sitosterol provided both antioxidant and antidiabetic effects. The results showed that beta-sitosterol reduced blood sugar levels in the rats, possibly due to increased insulin response. In another study, rats with diabetes taking 20 milligrams/kilograms of beta-sitosterol per day had normalized blood sugar and insulin levels at the end of 30 days of taking the supplement. Human trials on the effects of beta-sitosterol on diabetes are needed. Although animal trial results have been encouraging, it cannot be stated with certainty that beta-sitosterol will improve outcomes for people with diabetes. Other Potential Uses Beta-sitosterol has also been studied in the following conditions: Asthma Migraine Hair loss Inflammation Rheumatoid arthritis What Are the Side Effects of Beta-Sitosterol? Beta-sitosterol and other phytosterols are generally considered safe. But, as with any supplement or medication, side effects are possible. These side effects may be common or severe. Common Side Effects The most common side effects associated with taking beta-sitosterol are gastrointestinal. Common side effects of beta-sitosterol include: Diarrhea Fat in the stool Nausea Indigestion Gas Constipation Severe Side Effects Little to no severe side effects have been found in studies on beta-sitosterol and other phytosterols. When side effects do occur, they tend to be one of the common side effects just discussed. People with a rare genetic condition called sitosterolemia may be more likely to experience severe side effects. People with sitosterolemia are unable to absorb and excrete beta-sitosterol correctly. This leads to a buildup of beta-sitosterol, which can cause serious side effects like atherosclerosis and other health issues. To avoid side effects talk to your healthcare provider before taking beta-sitosterol supplements. Precautions Due to the lack of safety research, children and people who are pregnant or breastfeeding should avoid using beta-sitosterol. While no research has shown that beta-sitosterol is dangerous for these populations, there is not enough research to know if it is safe. As previously discussed, beta-sitosterol should not be used by people with sitosterolemia, a rare genetic disorder affecting the body's ability to use and get rid of beta-sitosterol properly. Narrowing of the arteries could occur if a person with sitosterolemia takes beta-sitosterol supplements. This could eventually result in blocked blood flow, increasing the risk of a heart attack or stroke. Taking more beta-sitosterol than is recommended on the label or by a healthcare provider could result in side effects. Getting advice and guidance from a knowledgeable healthcare provider before starting any new supplement is always best. Dosage: How Much Beta-Sitosterol Should I Take? Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your individual needs. There are no universal guidelines for how to use beta-sitosterol supplements, including dosage. A dose of 2 grams per day of beta-sitosterol has been found to be beneficial in lowering LDL cholesterol. Other research has suggested that taking up to 3.4 grams of beta-sitosterol daily can help lower high cholesterol, but taking more than 3.4 grams will provide no further benefits. For benign prostatic hyperplasia, a dose of 60 milligrams two times per day has been suggested. Talk with a healthcare provider to find the right beta-sitosterol dosage for you, What Happens if I Take Too Much Beta-Sitosterol? Beta-sitosterol is not thought to be toxic. An overdose is also not likely with this supplement. There is no upper limit (UL) in place for beta-sitosterol. An upper limit is a maximum quantity or dose that may cause adverse effects if exceeded. Since side effects are possible when taking beta-sitosterol, it's best to remain within the recommended dose provided by your healthcare provider or as listed on the supplement's label. Side effects, like those listed above, are more likely to happen if you take more than needed. Interactions Many supplements interact with other medications or nutrients. It is important to tell your healthcare provider about all the medications you are taking before starting a new supplement. Beta-sitosterol may interact with: Statins Zetia (ezetimibe) Carotenoids, a type of antioxidant found in plant foods that are orange, red, and yellow Statins Beta-sitosterol may interact with statins, a medication used to lower LDL cholesterol and reduce the risk of a heart attack or stroke. Statins may increase the absorption of beta-sitosterol. Ezetimibe Ezetimibe, another drug, may also interact with beta-sitosterol. Ezetimibe, also known as Zetia, also lowers LDL cholesterol and may block the absorption of beta-sitosterol in the body. Carotenoids A 2017 meta-analysis of randomized controlled trials found that phytosterols can interact with carotenoids. The analysis concluded that phytosterols reduced carotenoids in the blood. However, it's important to point out that this study did not differentiate the type of phytosterols used, so we do not know if beta-sitosterol was included in the review. It is essential to carefully read the ingredient list and nutrition facts label when choosing any supplement to know which ingredients and how much of each ingredient is included. Before starting beta-sitosterol, please review the supplement label with your healthcare provider to discuss potential interactions with foods, other supplements, and medications. Similar Supplements Some other supplements on the market may be similar to beta-sitosterol. It is not usually necessary (or recommended) to take two supplements for the same health condition. Talk with your healthcare provider about which supplement would be best for you and your health. Supplements that may be similar and used for the same health conditions as beta-sitosterol include: Pygeum: A herb that may be used to treat benign prostatic hyperplasia (BPH), pygeum has been used as an adjunct therapy for men with BPH and has been shown to improve symptoms and urine flow. Niacin: One of the B vitamins, niacin supplements have been used to treat high cholesterol. Niacin is thought to work by raising your HDL "good" cholesterol and lowering your LDL "bad" cholesterol. Alpha-lipoic acid: This supplement has also been studied in type 2 diabetes. It has been found to increase insulin sensitivity and improve glucose uptake by cells, resulting in lower blood sugar levels. Resveratrol: A polyphenol and antioxidant, resveratrol provides anti-inflammatory effects. It may help reduce low-grade inflammation. Biotin: A biotin deficiency can result in hair loss. Taking biotin (one of the B vitamins your body needs) may help with hair loss. Sources of Beta-Sitosterol and What to Look For Beta-sitosterol and other phytosterols are widely available in food. Because of this, it is easy for most people to get plenty of beta-sitosterol through their diet. A food-first approach to all nutrients is best, including beta-sitosterol. However, a beta-sitosterol supplement may sometimes be needed, for example, when a healthcare provider recommends it. Food Sources of Beta-Sitosterol Beta-sitosterol is found in plant-based foods. Many foods contain beta-sitosterol, including nuts, oils, wheat, and beans. Good food sources of beta-sitosterol include, but are not limited to: Vegetable oils Peas Avocados Peanuts Almonds Kidney beans Soybeans Wheat germ Walnuts Lentils There are many ways to fit these and other beta-sitosterol-containing foods into your diet. While nuts make great snacks, beans or lentils can make great side dishes. Cooking with vegetable oil is thought to be heart-healthy. Beta-Sitosterol Supplements You can find beta-sitosterol supplements in capsule, tablet, or soft gel form. Some versions of the supplement are vegan or gluten-free. Other ingredients may be present in beta-sitosterol supplements, such as fish oil, magnesium, or soy. Remember to check the product label for any ingredients you are allergic to before purchasing a beta-sitosterol supplement. In the United States, the Food and Drug Administration (FDA) does not regulate supplements the way it regulates prescription drugs. That means some supplement products may not contain what the label says. When choosing a supplement, look for third-party tested products and consult a healthcare provider, registered dietitian nutritionist (RD or RDN), or pharmacist. Summary Beta-sitosterol is a phytosterol that is found in plants. Beta-sitosterol is sometimes used to reduce cholesterol levels because it is similar in structure to cholesterol. It has also been studied for its role in improving symptoms of benign prostatic hyperplasia. Although beta-sitosterol is available in supplement form, many everyday foods like nuts, beans, and vegetable oils also contain it. Side effects of beta-sitosterol are typically not severe and may only occur if you take more than is recommended. Therefore, beta-sitosterol is recognized as a generally safe supplement. Always speak with a healthcare provider before starting a new supplement, and be sure to share any health conditions you may have or medications you are taking. Frequently Asked Questions Are beta-sitosterol supplements safe for benign prostatic hyperplasia? Beta-sitosterol supplements appear to be safe for most men who take them for BPH. For some people, though, beta-sitosterol may cause an upset stomach or other gastrointestinal side effects.If you experience side effects from taking beta-sitosterol for BPH, check with your healthcare provider to be sure that your symptoms are not related to a different condition that needs other treatment. Learn More What Is BPH, or Enlargement of the Prostate? Is beta-sitosterol a blood thinner? For heart health, beta-sitosterol works by lowering the amount of LDL "bad" cholesterol in your blood because it is thought to block cholesterol absorption. However, research has not shown that beta-sitosterol also acts as a blood thinner.Researchers are looking to see if beta-sitosterol may have other benefits for heart health, including preventing blood clots, but the research is not sufficient yet. Learn More Blood Thinners: What You Should Know Do I need to take a beta-sisoterol supplement? It is always best to get the nutrients you need from food first. However, sometimes it can be difficult for some people to get a variety of nutritious foods into their diet, and supplements can be the answer.Also, if beta-sitosterol supplements have been recommended to you by a healthcare provider due to a health condition, then a supplement may be warranted. Learn More Dietary Supplements 25 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Babu S, Jayaraman S. An update on β-sitosterol: a potential herbal nutraceutical for diabetic management. Biomed Pharmacother. 2020;131. doi:10.1016/j.biopha.2020.110702 Bin Sayeed MS, Karim SMR, Sharmin T, Morshed MM. Critical analysis on characterization, systemic effect, and therapeutic potential of beta-sitosterol: a plant-derived orphan phytosterol. Medicines. 2016;3(4):29. doi:10.3390/medicines3040029 U.S. Food and Drug Administration. CFR - Code of Federal Regulations Title 21. Wilt T, Ishani A, MacDonald R, Stark G, Mulrow C, Lau J. Beta-sitosterols for benign prostatic hyperplasia. Cochrane Database Syst Rev. 2000;1999(2):CD001043. doi:10.1002/14651858.CD001043 Bin Sayeed MS, Ameen SS. Beta-sitosterol: a promising but orphan nutraceutical to fight against cancer. Nutr Cancer. 2015;67(8):1214-1220. doi:10.1080/01635581.2015.1087042 Baskar AA, Ignacimuthu S, Paulraj GM, Al numair KS. Chemopreventive potential of beta-Sitosterol in experimental colon cancer model--an in vitro and In vivo study. BMC Complement Altern Med. 2010;10:24. Awad AB, Roy R, Fink CS. Beta-sitosterol, a plant sterol, induces apoptosis and activates key caspases in MDA-MB-231 human breast cancer cells. Oncol Rep. 2003;10(2):497–500. Gupta R, Sharma AK, Dobhal MP, Sharma MC, Gupta RS. Antidiabetic and antioxidant potential of β-sitosterol in streptozotocin-induced experimental hyperglycemia. J Diabetes. 2011;3(1):29-37. doi:10.1111/j.1753-0407.2010.00107.x Mahajan S, Mehta A. Suppression of ovalbumin-induced Th2-driven airway inflammation by β-sitosterol in a guinea pig model of asthma. Eur J Pharm. 2011;650(1):458-464. doi:10.1016/j.ejphar.2010.09.075 Saeidnia S, Manayi A, Gohari A, Abdollahi M. The story of beta-sitosterol-a review. European Journal of Medicinal Plants. 2014;4(5):590-609. National Center for Complementary and Integrative Health. High cholesterol and natural products: what the science says. Science Direct. Sitosterol - an overview | sciencedirect topics. Tada H, Nohara A, Inazu A, et al. Hypercholesterolemia, and coronary artery disease. J Atheroscler Thromb. 2018;25(9):783-789. doi:10.5551/jat.RV17024 MedlinePlus. Sitosterolemia. National Cholesterol Education Program. ATP III Guidelines: at-a-glance quick desk reference. Science Direct. Beta-Sitosterol. Miettinen TA, Gylling H. Effect of statins on noncholesterol sterol levels: implications for use of plant stanols and sterols. Am J Cardiol. 2005;96(1A):40D-46D. doi:10.1016/j.amjcard.2005.03.019 Salen G, Bergmann KV, Lütjohann D, et al. Ezetimibe effectively reduces plasma plant sterols in patients with sitosterolemia. Circulation. 2004;109;966-971. doi:10.1161/01.CIR.0000116766.31036.03 Baumgartner S, Ras RT, Trautwein EA, Mensink RP, Plat J. Plasma fat-soluble vitamin and carotenoid concentrations after plant sterol and plant stanol consumption: a meta-analysis of randomized controlled trials. Eur J Nutr. 2017;56(3):909-923. doi:10.1007/s00394-016-1289-7 Cicero AFG, Allkanjari O, Busetto GM, et al. Nutraceutical treatment and prevention of benign prostatic hyperplasia and prostate cancer. Arch Ital Urol Androl. 2019;91(3):10.4081/aiua.2019.3.139. doi:10.4081/aiua.2019.3.139 Medline Plus. Niacin for cholesterol. Salehi B, Berkay Yılmaz Y, Antika G, et al. Insights on the use of α-lipoic acid for therapeutic purposes. Biomolecules. 2019;9(8):356. doi:10.3390/biom9080356. Chaplin A, Carpéné C, Mercader J. Resveratrol, metabolic syndrome, and gut microbiota. Nutrients. 2018;10(11):1651. doi:10.3390/nu10111651 Almohanna HM, Ahmed AA, Tsatalis JP, Tosti A. The role of vitamins and minerals in hair loss: a review. Dermatol Ther (Heidelb). 2019;9(1):51-70. doi:10.1007/s13555-018-0278-6 Zhang Y, Zhuang P, Wu F, et al. Cooking oil/fat consumption and deaths from cardiometabolic diseases and other causes: prospective analysis of 521,120 individuals. BMC Med. 2021;19:92. doi:10.1186/s12916-021-01961-2 Additional Reading AbuMweis S, Marinangeli C, Frohlich J. et al. Implementing phytosterols into medical practice as a cholesterol-lowering strategy: overview of efficacy, effectiveness and safety. Can J Cardiol. 2014;30:1225-1232. doi:10.1016/j.cjca.2014.04.022 Awad AB, Barta SL, Fink CS, and Bradford PG. Beta-Sitosterol enhances tamoxifen effectiveness on breast cancer cells by affecting ceramide metabolism. Mol Nutr Food Res. 2008;52(4):419-426. Wilt TJ, MacDonald R, Ishani A. Beta-sitosterol for the treatment of benign prostatic hyperplasia: a systematic review. BJU Int. 1999;83(9):976-983. By Brittany Lubeck, MS, RDN Lubeck is a registered dietitian and freelance nutrition writer with a master's degree in clinical nutrition. Originally written by Cathy Wong See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit