What is beta-sitosterol?

Phytosterols (plant sterols) are lipophilic substances found in plant cell membranes that have a similar chemical structure to cholesterol. More than 100 different phytosterols are known, with beta-sitosterol being the most common. Chemically speaking, beta-sitosterol is a plant sterol ester. It is found in fruits, vegetables, nuts, and seeds.

Therapeutic applications

prostate

Official statistics show that over 60 percent of all men aged 60 suffer from an enlarged prostate, and that as many as 90 percent of men aged 85 and over suffer from this problem.

The fact that beta-sitosterol alleviates symptomatic benign prostatic hyperplasia (LUTS/BPH) is partly due to its anti-inflammatory, antioxidant, and anti-androgenic effects (beta-sitosterol inhibits the enzyme 5-alpha reductase).

A 2000 study review concluded that beta-sitosterol alleviates the symptoms of benign prostatic hyperplasia (BPH).u.a. improved urine flow), but did not result in a reduction in the size of the prostate (cf. https://pubmed.ncbi.nlm.nih.gov/10796740/).

Several studies suggest that beta-sitosterol can improve urinary tract symptoms, including urine flow strength. This was also reflected in a significant improvement in the International Prostate Symptom Score, which measures the severity of symptoms of an enlarged prostate (see [reference]). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3798925/ , https://pubmed.ncbi.nlm.nih.gov/10792163/ , https://pubmed.ncbi.nlm.nih.gov/7540705/ , https://pubmed.ncbi.nlm.nih.gov/9313662/ and https://pubmed.ncbi.nlm.nih.gov/10796740/).

Beta-sitosterol appears to work through similar mechanisms to the prescription drug Procar, by inhibiting the 5-alpha reductase enzyme responsible for the production of DHT in the body (see [reference]). https://pubmed.ncbi.nlm.nih.gov/12006122/DHT is one of the primary hormones involved in benign prostatic hyperplasia (BPH).

Beta-sitosterol can also relieve swelling and inflammation of the prostate, which in turn can reduce pain and urinary urgency. Additionally, this can lead to a reduction in the amount of urine remaining in the bladder, which can contribute to a feeling of relief after urination.

Furthermore, beta-sitosterol can reduce the amount of estrogen produced in the male body by inhibiting the aromatase enzyme. Since beta-sitosterol acts as an estrogen receptor agonist, binding to estrogen receptors without generating significant estrogenic effects, it can serve as an estrogen receptor blocker, reducing the effects of existing estrogen (see [reference]). https://pubmed.ncbi.nlm.nih.gov/15113961/This can lead to a relief of prostate problems, as estrogen, alongside DHT, is the second primary hormonal factor that contributes to prostate enlargement.

cholesterol

One of the most common uses for beta-sitosterol is to reduce the absorption of cholesterol in the digestive tract (see below). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3296732/). This can lower levels of “bad” LDL cholesterol.

Experts recommend consuming at least 2 grams of plant sterols such as beta-sitosterol in the form of healthy foods like nuts and seeds to support the maintenance of healthy cholesterol levels. Studies show that beta-sitosterol can lower levels of "unhealthy" LDL cholesterol without negatively affecting levels of "healthy" HDL cholesterol (see [reference]). https://www.ahajournals.org/doi/pdf/10.1161/01.CIR.10.2.201).

antioxidant

Beta-sitosterol possesses antioxidant properties that can protect the body's cells from oxidative damage. For example, one study showed that beta-sitosterol can reduce oxidative damage associated with diabetes by increasing antioxidant levels in the pancreas (see [reference]). https://www.researchgate.net/publication/49669785_Antidiabetic_and_antioxidant_potential_of_b-sitosterol_in_Streptozotocin-induced_experimental_hyperglycemia).

Blood sugar

Beta-sitosterol has shown positive results in studies when it comes to stimulating insulin secretion and reducing blood sugar levels (see [reference]). https://www.researchgate.net/publication/339638999_Effect_of_b-sitosterol_on_glucose_homeostasis_by_sensitization_of_insulin_resistance_via_enhanced_protein_expression_of_PPRg_and_glucose_transporter_4_in_high_fat_diet_and_streptozotocin-induced_diabe).

Furthermore, it was able to lower levels of glycated hemoglobin, which is a measure of the damage caused by permanently elevated blood sugar levels (see [reference]). https://www.researchgate.net/publication/49669785_Antidiabetic_and_antioxidant_potential_of_b-sitosterol_in_Streptozotocin-induced_experimental_hyperglycemia).

Cancer

Studies suggest that beta-sitosterol may be able to induce apoptosis (programmed cell death) in cancer cells and inhibit the growth of colon and breast cancer cells (see [reference]). https://pubmed.ncbi.nlm.nih.gov/17266177/).

The combination of beta-sitosterol and gemcitabine has shown synergistic activity against pancreatic cancer based on preclinical studies.

In addition to reducing benign prostatic hyperplasia (BPH), beta-sitosterol may also reduce the risk of prostate cancer and inhibit its growth. A study using LNCaP cell line prostate cancer cells (an androgen-dependent tumor) showed that beta-sitosterol reduced cancer cell growth by 24% and quadrupled induced apoptosis. This was accompanied by a 50% increase in ceramide production (see [reference]). https://pubmed.ncbi.nlm.nih.gov/9824850/).

Scientific studies suggest that ceramide induces apoptosis (see...). https://pubmed.ncbi.nlm.nih.gov/15796189/In another study, beta-sitosterol was able to reduce the growth of androgen-dependent human prostate cancer cells by 70% compared to a placebo (see [reference]). https://pubmed.ncbi.nlm.nih.gov/11916349/).

skin && Hair

Beta-sitosterol, in combination with saw palmetto extract, can inhibit androgenic alopecia. It has a hormone-like structure and can also reduce unwanted effects of the male hormone, such as oily skin, acne, or increased body hair.

dosage

The following dosages were investigated in scientific studies:

• For benign prostatic hyperplasia: 60 to 130 mg of beta-sitosterol per day, divided into 2-3 individual doses.
• Dosage recommendations for lowering LDL cholesterol levels are at least 200 mg or more per day.

Safety and interactions

Supplementation with beta-sitosterol at the dose specified in the usage recommendations is safe and generally well tolerated. Occasionally, (mild) gastrointestinal discomfort occurs. The permissible daily dose is set at approximately 40 mg per kg of body weight per day.

· Pregnancy and breastfeeding: Not enough is known about the use of beta-sitosterol during pregnancy and breastfeeding, therefore pregnant and breastfeeding women should avoid beta-sitosterol.

· Sitosterolemia (a rare inherited fat storage disorder): People with this condition have too much beta-sitosterol and related fats in their bodies. They are more susceptible to early-onset heart disease. Taking beta-sitosterol worsens this condition, which is why people with sitosterolemia should not take beta-sitosterol.

· Beta-sitosterol has a cholesterol-lowering effect. People taking cholesterol-lowering medication should take this into account and discuss the dosage with their doctor.

Sources

· Gupta E. β-Sitosterol: predominant phytosterol of therapeutic potential. Innovations in Food Technology. 2020:465-477.

· Bin Sayeed MS et al. Critical analysis on characterization, systemic effect, and therapeutic potential of beta-sitosterol: a plant-derived orphan phytosterol. Medicines (Basel). 2016;3(4):29.

· Sudeep HV et al. A double blind, placebo-controlled randomized comparative study on the efficacy of phytosterol-enriched and conventional saw palmetto oil in mitigating benign prostate hyperplasia and androgen deficiency. BMC Urol. 2020;20(1):86.

· Wilt TJ et al. Beta-sitosterol for the treatment of benign prostatic hyperplasia: a systematic review. BJU International 1999;83:976-83.

· Wilt T et al. Beta-sitosterols for benign prostatic hyperplasia. Cochrane Database Syst Rev. 2000;(2):CD001043.

· by Holtz RL et al. Beta-sitosterol activates the sphingomyelin cycle and induces apoptosis in LNCaP human prostate cancer cells. Nutr Cancer. 1998;32(1):8-12.

· Prager N et al. 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):143-52.

· Chen S et al. Serum cholesterol-lowering activity of beta-sitosterol laurate is attributed to the reduction of both cholesterol absorption and bile acids reabsorption in hamsters. J Agric Food Chem. 2020;68(37):10003-10014.

· Tovey FI et al. Dietary phytosterols protect against peptic ulceration.Gastroenterology Res. 2011;4(4):149-156.

· Tovey FI. Role of dietary phospholipids and phytosterols in protection against peptic ulceration as shown by experiments on rats. World J Gastroenterol. 2015;21(5):1377-84.

· Sun Y et al. Beta-sitosterol alleviates inflammatory response via inhibiting the activation of ERK/p38 and NF-kappaB pathways in LPS-exposed BV2 cells. Biomed Res Int. 2020;2020:7532306.

· Liu R et al. Beta-sitosterol modulates macrophage polarization and attenuates rheumatoid inflammation in mice. Pharm Biol. 2019;57(1):161-168.

· Babu S et al. An update on β-sitosterol: a potential herbal nutraceutical for diabetic management. Biomed Pharmacother. 2020;131:110702.

· Lin F et al. Beta-sitosterol protects against myocardial ischemia/reperfusion injury via targeting PPARgamma/NF-kappaB signaling. Evid Based Complement Alternat Med. 2020;2020:2679409.

· Panayotis N et al. Beta-sitosterol reduces anxiety and synergizes with established anxiolytic drugs in mice. Cell Rep Med 2021;2(5):100281.

· Ayaz M et al. Anti-Alzheimer's studies on beta-sitosterol isolated from Polygonum hydropiper L. Front Pharmacol. 2017;8:697.

· Alvarez-Sala A et al. Apoptotic effect of a phytosterol-ingredient and its main phytosterol (beta-sitosterol) in human cancer cell lines. Int J Food Sci Nutr. 2019;70(3):323-334.

· Chen Z et al. Beta-sitosterol attenuates liver injury in a rat model of chronic alcohol intake. Arch Pharm Res. 2020;43(11):1197-1206.

Cao ZQ et al. Beta-sitosterol and gemcitabine exhibit synergistic anti-pancreatic cancer activity by modulating apoptosis and inhibiting epithelial-mesenchymal transition by deactivating Akt/GSK-3beta signaling. Front Pharmacol. 2019;9:1525.