Beta-sitosterol is a phytosterol, a type of alcohol that occurs naturally in plants. Its chemical structure is very similar to that of cholesterol. In fact, beta-sitosterol is added to certain foods, such as margarine and mayonnaise, to reduce the absorption of dietary cholesterol. Beta-sitosterol is also reputed to help prevent hair loss. Hair loss can be a sign of disease, though, so be sure to see your doctor to rule out a serious medical condition before you try to deal with hair loss on your own.
The results of the first placebo-controlled, double-blind study on the effectiveness of natural 5-alpha-reductase type II inhibitors, namely beta-sitosterol, were published in the April 8, 2002 issue of the Journal of Alternative and Complementary Medicine. Lead researcher Nelson Prager reported that beta-sitosterol promoted significant improvement in six out of 10 male study subjects with mild-to-moderate androgenetic alopecia, or male pattern balding. The Aug. 19, 2009 issue of Evidence-based Complementary and Alternative Medicine featured a study that showed that beta-sitosterol, in combination with two anti-inflammatory agents, successfully altered gene expression and inhibited inflammation in cultured human skin cells that simulated the characteristics of androgenetic alopecia.
Naturally Grown Substance
Beta-sitosterol is found in several cereal grains, cane sugar, soybeans, corn, avocados, pumpkin seeds and pecans. This agent is also found in the berries of certain herbs, most notably saw palmetto and sea buckthorn. According to the online database at Drugs.com, beta-sitosterol is most commonly extracted from unrefined peanut oil, avocado oil and soybean oil.
In terms of hair loss prevention, the main action of beta-sitosterol is to inhibit the expression of 5-alpha-reductase type II, the enzyme primarily responsible for the conversion of testosterone into dihydrotestosterone, or DHT. This secondary hormone is actually far more potent than testosterone, and plays a major role in male sexual development and physical characteristics. In your youth, DHT promoted the growth of facial hair and the deepening of your voice. However, with the passage of time, the receptor sites for this hormone begin to respond differently. Ironically, chest and facial hair follicles are stimulated to produce more growth, but as more and more DHT binds to hair follicle receptors on the scalp they start to become dormant. New growth on your head becomes progressively thinner until the hairs can no longer even break through the skin. Declining levels of testosterone also affect hair growth in women as they age, although estrogen affords some counter effects. After menopause, however, a woman is vulnerable to hair loss as well.
Beta-sitosterol is a member of a family of 60 plant sterols that also includes campesterol, stigmasterol and brassicasterol. Although this substance is chemically similar to and behaves the same way as cholesterol, the two are inherently different. For one thing, cholesterol is a sterol that is specifically found in the cell membranes of mammals. Beta-sitosterol, on the other hand is found in the cell membranes of both animals and plants. In addition, beta-sitosterol is not well absorbed in the intestines or manufactured by the body as cholesterol is. According to a science advisory issued by the American Heart Association Nutrition Committee in the journal Circulation, the supplemental form of beta-sitosterol, as well as the type added to fortified foods, is modified into liposterolic compounds to increase solubility in fats.
Dos and Don'ts
The American Heart Association says that there are few risks associated with beta-sitosterol supplementation. However, some individuals may experience a decrease in the absorption of other nutrients, or may be prone to absorbing high levels of plant sterols. Talk to your doctor before using beta-sitosterol to treat hair loss.