Gamma oryzanol's therapeutic uses
Gamma oryzanol is a natural compound derived from rice bran oil, primarily recognized for its potential therapeutic uses, particularly in managing high cholesterol levels. Approved in Japan for various health conditions, it is often sought for its possible benefits in heart disease prevention, alleviating menopausal symptoms, and enhancing sports performance. While some users believe gamma oryzanol can improve muscle growth and athletic performance by influencing hormone levels, scientific evidence does not strongly support these claims. Research indicates it may aid in cholesterol absorption and exhibit antioxidant properties, but substantial clinical trials are still needed to confirm its effectiveness for many of these uses. Additionally, gamma oryzanol has been investigated for its potential to alleviate symptoms of eczema, lower blood pressure, and possibly assist with anxiety and diabetes management. Despite its popularity, especially as a dietary supplement, its safety profile seems generally favorable, although specific guidelines for certain vulnerable populations remain to be established. As with any supplement, individuals are encouraged to consult healthcare professionals before starting use, particularly to discuss potential risks and benefits.
Gamma oryzanol's therapeutic uses
- DEFINITION: Natural plant product used to treat specific health conditions.
- PRINCIPAL PROPOSED USE: High cholesterol
- OTHER PROPOSED USES: Heart disease prevention, menopausal symptoms, sports performance and bodybuilding, ulcer prevention, eczema, high blood pressure
Overview
Gamma oryzanol is a mixture of substances derived from rice bran oil, including sterols and ferulic acid. It has been approved in Japan for several conditions, including menopausal symptoms, mild anxiety, stomach upset, and high cholesterol. In the United States, it is widely used as a sports supplement and for reducing cholesterol. However, meaningful evidence supporting the use of gamma oryzanol for any of these purposes has only just begun to emerge, and more studies are necessary.
Requirements and Sources
There is no daily requirement for gamma oryzanol. Rice bran oil is the principal source of gamma oryzanol, but it is also found in the bran of wheat and other grains and in various fruits, vegetables, and herbs. However, to get enough gamma oryzanol to reach typical therapeutic dosages, one needs to take supplements.
Therapeutic Dosages
A typical dosage of gamma oryzanol is 500 milligrams (mg) daily.
Therapeutic Uses
Like many other vegetable oils, rice bran oil improves cholesterol profile. Preliminary evidence, including small double-blind, placebo-controlled trials, suggests that the gamma oryzanol portion of rice bran oil may contribute an additional cholesterol-lowering benefit beyond the effects of the fatty acids. Gamma oryzanol is thought to work by impairing cholesterol absorption in the digestive tract.
Additionally, gamma oryzanol has antioxidant properties. It has been hypothesized that antioxidants can help protect against heart disease, cancer, and other illnesses; however, gigantic studies looking for such benefits with the antioxidants vitamin E and beta-carotene have returned negative results.
Gamma oryzanol is used by some athletes based on early reports that suggested gamma oryzanol enhances muscle growth and sports performance. According to numerous Internet sites, gamma oryzanol produces these benefits by increasing levels of testosterone, growth hormone, and other anabolic (muscle-building) hormones. However, there is no scientific evidence that gamma oryzanol either affects these hormones or enhances performance, and there is some evidence that it does not. For example, a double-blind, placebo-controlled study found that nine weeks’ consumption of gamma oryzanol at a dose of 500 mg daily affected neither anabolic hormone levels nor performance. A study in 2014 showed similarly conflicting results—while study subjects taking gamma oryzanol showed no overall anthropometric gains, there was evidence of improved muscle strength when gamma oryzanol was combined with resistance training. Evidence from animal studies suggests that gamma oryzanol may help prevent ulcers, but meaningful human trials are lacking.
Gamma oryzanol has also been advocated as a treatment for menopausal symptoms, but the basis of this potential use consists of evidence far too weak to be relied upon. One study in humans found that supplementation with gamma oryzanol decreased hot flashes in study participants. In another study, gamma oryzanol injected into rats altered levels of circulating luteinizing hormone (LH). This, in turn, might conceivably help menopausal symptoms, but it is a long way from theoretical benefits in rats to proof of effectiveness in humans. One open study, sometimes touted as direct evidence for benefit in menopause, lacked a control group and therefore meant nothing.
Several other proposed therapeutic uses for gamma oryzanol need increased scientific study. Preliminary studies indicate it may help reduce inflammation associated with eczema and lower blood pressure. Gamma oryzanol has also been studied for its potential role in diabetes management, anxiety, cognitive function, and certain types of cancer.
Safety Issues
In the late 1970s, a batch of rice bran oil was contaminated by polychlorinated biphenyls (PCBs), resulting in the poisoning of more than two thousand people. This led to studies on the safety of gamma oryzanol products. On balance, the results of these investigations suggest that gamma oryzanol, when taken at normal doses, is nontoxic and noncarcinogenic. However, the maximum safe dosages for young children, pregnant or nursing women, and those with severe liver or kidney disease have not been established.
Bibliography
Berger, A., et al. "Similar Cholesterol-Lowering Properties of Rice Bran Oil, with Varied Gamma-Oryzanol, in Mildly Hypercholesterolemic Men." European Journal of Nutrition, vol. 44, no. 3, 2005, pp. 163-173.
Cicero, A. F., and A. Gaddi. "Rice Bran Oil and Gamma-Oryzanol in the Treatment of Hyperlipoproteinaemias and Other Conditions." Phytotherapy Research, vol. 15, 2001, pp. 277-289.
Eslami, Saghar, et al. "Effects of Gamma Oryzanol Supplementation on Anthropometric Measurements & Muscular Strength in Healthy Males following Chronic Resistance Training." The Indian Journal of Medical Research, vol. 139, no. 6, 2014, pp. 857-863, www.ncbi.nlm.nih.gov/pmc/articles/PMC4164998. Accessed 20 Aug. 2023.
"Gamma-Oryzanol: Overview, Uses, Side Effects, Precautions, Interactions, Dosing and Reviews." WebMD, www.webmd.com/vitamins/ai/ingredientmono-770/gamma-oryzanol. Accessed 25 Sept. 2024.
"Gamma Oryzanol Uses, Benefits & Side Effects." Drugs.com, www.drugs.com/npc/gamma-oryzanol.html. Accessed 25 Sept. 2024.
Most, M. M., et al. "Rice Bran Oil, Not Fiber, Lowers Cholesterol in Humans." American Journal of Clinical Nutrition, vol. 81, 2005, pp. 64-68.
Nikooyeh, Bahareh, et al. "Daily Consumption of γ-Oryzanol-Fortified Canola Oil, Compared with Unfortified Canola and Sunflower Oils, Resulted in a Better Improvement of Certain Cardiometabolic Biomarkers of Adult Subjects with Type 2 Diabetes: A Randomized Controlled Clinical Trial." European Journal of Medical Research, vol. 28, no. 1, 10 Oct. 2023, p. 416, doi.org/10.1186/s40001-023-01409-8. Accessed 25 Sept. 2024.