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.
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).
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.
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.
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.
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.