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RELATED TERMS
Beta-sitosterol, beta-sitosteryl ferulate calclate, campestrol, campesteryl ferulate, compestanyl ferulate, crude rice bran oil, cycloartanol, cycloartenol, cycloartenyl ferulate, cycloaternol, cyclobranol, ferulic acid, ferulic acid derivatives, ferulic acid esters, gamma-orizanol, gamma-oryzanol, gamma-Oryzanol Fine Particle, gamma-oz, gammariza, gammatsul, guntrin, Hi-Z©, maspiron, oliver, oryvita, oryzaal, oryzanol, oz, rice bran oil, sitostanyl ferulate sitosteryl ferulate, sterols, stigmasterol, stigmasteryl ferulate, thiaminogen, triterpene alcohol, triterpenyl alcohol.
BACKGROUND
Gamma oryzanol is a mixture of ferulic acid esters of sterol and triterpene alcohols, and it occurs in rice bran oil at a level of 1-2%, although it has been extracted from corn and barley oils as well. It is theorized that some of the health benefits from rice bran oil, namely, its cholesterol-lowering effects, may be due to its gamma oryzanol content.
Gamma oryzanol was first isolated and purified in the 1950s. In the 1960s, it was used medically in Japan for anxiety. Each year Japan manufactures 7,500 tons of gamma oryzanol from 150,000 tons of rice bran. Not surprisingly, most of the research on oryzanol has been performed in Japan.
Gamma oryzanol is frequently sold as a bodybuilding aid, specifically to increase testosterone levels, stimulate the release of endorphins (pain-relieving substances made in the body), and promote the growth of lean muscle tissue. However, most currently available studies do not support these claims.
EVIDENCE TABLE
Conditions
| Uses disclaimer: 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. | Grade* |
Hyperlipidemia (high cholesterol)Preliminary evidence indicates that gamma oryzanol may reduce hyperlipidemia. Gamma oryzanol seems to reduce total cholesterol, LDL, HDL and triglycerides. Additional study is needed to establish gamma oryzanol's effect on hyperlipidemia. | B |
GastritisLittle research has been done on the effects of gamma oryzanol on gastritis. Additional study is needed to assess its potential use. | C |
HypothyroidismPreliminary evidence has indicated that gamma oryzanol affects several parts of the endocrine system, and may reduce thyroid stimulating hormone (TSH) in patients with hypothyroidism. More studies are needed in this area and other areas of endocrinology to establish gamma oryzanol's effects. | C |
Menopausal symptomsGamma oryzanol may reduce menopausal symptoms. However, these results must be viewed cautiously as treatment of menopause symptoms has a high placebo effect. Additional study is needed in this area to elucidate gamma oryzanol's effect on menopausal symptoms. | C |
Prevention of restenosis after coronary angioplasty (PTCA)Gamma oryzanol has been used to reduce restenosis (return of blood vessel blockages after treatment) after coronary dilation, in combination with ticlopidine and probucol. Although restenosis was not impacted by any of the treatments, study with gamma oryzanol alone is needed to establish its effect on restenosis. | C |
Skin conditionsA few studies have used gamma oryzanol by mouth or applied on the skin to treat skin conditions. Although these studies seem to indicate that gamma oryzanol may be useful, additional study needed to assess gamma oryzanol's effects. | C |
BodybuildingGamma oryzanol has been touted as a bodybuilding aid, specifically to increase testosterone levels, stimulate the release of endorphins (pain-relieving substances made in the body), and promote the growth of lean muscle tissue. However, there is little or no evidence to support these claims. Additional study is needed to establish gamma oryzanol's effect on bodybuilding. | D |
*Key to grades: A: Strong scientific evidence for this use; B: Good scientific evidence for this use; C: Unclear scientific evidence for this use; D: Fair scientific evidence against this use (it may not work); F: Strong scientific evidence against this use (it likely does not work). | |
TRADITION
The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below. Anemia, anticoagulant, anti-inflammatory, antioxidant, anxiety, atherosclerosis (hardening of the arteries), atopic dermatitis, body fat reducer, cancer, central nervous system disorders (autonomic imbalance), cosmetics, diabetes, digestive complaints, fatty liver, food uses, gynecologic disorders (hypoovarianism), heartburn, heart disease, hypercalciuria (excessive amounts of calcium in the urine), immunostimulant, kidney stones, muscle soreness, nausea, nervous system function (suppressant), pain, sports or other physical injuries, exercise recovery, ulcers, vomiting, whiplash.DOSING
disclaimer: The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
Adults (over 18 years old)
There is no proven effective dose for gamma oryzanol. A common dose of gamma oryzanol is 300 milligrams, which has been taken up to six months for hyperlipidemia (high cholesterol). This dose has also been used for hypothyroidism as a single dose. Another common dose is 100 milligrams of Hi-Z© (Otsuka Pharmaceutical Co, Tokyo, Japan), which has been has been taken for skin conditions (up to four weeks) or hyperlipidemia (up to sixteen weeks). For bodybuilding, 500 milligrams daily has been used according to manufacturer's instructions for up to nine weeks. For menopausal symptoms or hyperlipidemia, 1.5 grams of gamma oryzanol Fine Particle (300 milligrams gamma oryzanol included) for up to eight weeks has been used.
Children (under 18 years old)
There is no proven effective dose for gamma oryzanol in children. However, 20 milliliters of 0.5% gamma oryzanol solution has been dissolved in the bathtub to form a medicinal bath for up to six months in children.
SAFETY
disclaimer: The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Allergies
Avoid in individuals with a known allergy or hypersensitivity to gamma oryzanol, its components, or rice bran oil.
Side Effects and Warnings
Many clinical trials have been conducted and reported no adverse effects with gamma oryzanol. It is likely safe when taken at normal doses, and it is not considered toxic or carcinogenic (cancer causing).
Pregnancy & Breastfeeding
Gamma oryzanol is not recommended in pregnant or breastfeeding women due to a lack of available scientific evidence. Although not well studied in humans, gamma oryzanol may alter hormone production.
INTERACTIONS
disclaimer: Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.
Interactions with Drugs
Although not well studied in humans, oryzanol combined with a high cholesterol diet may increase the risk of bleeding. Gamma oryzanol has also shown significant cholesterol-lowering effects. Caution is advised when taking gamma oryzanol with other cholesterol-lowering agents due to additive effects.
In pharmacological tests, cycloartenol ferulic acid ester, a component of gamma oryzanol, may have a suppressant effect on the central nervous system; its properties seemed different from those of existing major and minor tranquilizers.
Although not well studied in humans, gamma oryzanol may suppress growth hormone synthesis, prolactin release, and luteinizing hormone release.
Gamma oryzanol may increase insulin sensitivity in diabetics. Patients taking insulin or agents that alter blood sugar levels should use gamma oryzanol with caution. Dosing adjustments may be necessary.
Gamma oryzanol may moderately stimulate the immune system and caution is advised in patients taking immunomodulating agents.
Gamma oryzanol may reduce thyroid-stimulating hormone (TSH) in patients with hypothyroidism.
Interactions with Herbs & Dietary Supplements
Although not well studied in humans, oryzanol combined with a high cholesterol diet may increase the risk of bleeding. Caution is advised.
In pharmacological tests, cycloartenol ferulic acid ester, a component of gamma oryzanol, may have a suppressant effect on the central nervous system; its properties seemed different from those of existing major and minor tranquilizers.
Although not well studied in humans, gamma oryzanol may increase insulin sensitivity in diabetics. Patients using herbs that alter blood sugar levels should use gamma oryzanol with caution. Dosing adjustments may be necessary.
Gamma oryzanol may moderately stimulate the immune system. Caution is advised in patients taking immunomodulating herbs due to possible additive effects.
Gamma oryzanol may reduce thyroid stimulating hormone (TSH) in patients with hypothyroidism.
ATTRIBUTION
This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).
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Copyright © 2011 Natural Standard (www.naturalstandard.com)
Copyright © 2011 Natural Standard (www.naturalstandard.com)
