What is Gamma Oryzanol?

[Aim Star Network’s Rice Bran & Germ Oil : Gamma oryzanol is
extracted from
Thai Jasmine rice bran oil]



Gamma oryzanol is a mixture of ferulic acid esters of sterols and triterpene alcohols, extracted from rice bran oil and other grain oils such as corn and barley. Ferulic acid compounds also are present in many foods, including oats, berries, citrus fruits, tomatoes, olives, and vegetables. Gamma oryzanol serves as an important antioxidant within plant cells.

What is Gamma Oryzanol used for? It products can be divided into 5 groups as below.

Traditional/Ethnobotanical uses

Early reports from the mid-1950s reported isolation, extraction, and purification of gamma oryzanol. However, the Japanese have been using it as a medicine since 1962. It first was used to treat anxiety. In the 1970s it was found to be an effective treatment for menopause. Gamma oryzanol therapy was approved to treat elevated cholesterol and triglyceride levels in the late 1980s.

Menopause

Gamma oryzanol has been proven effective to treat symptoms of menopause, such as hot flashes and aging syndromes. One report found a 50% reduction of menopausal symptoms in about 70% of patients. The proposed mechanisms of action are the reduction in secretion of leutinizing hormone by the pituitary gland and promotion of endorphin release by the hypothalamus. The overall importance of these effects has not been fully determined. More human clinical trials are needed.

Hyperlipidemia

Human studies using gamma oryganol for hyperlipidemias also are promising. Reduced total cholesterol and triglyceride levels, and increased HDL levels were noted in hyperlipidemic patients given gamma oryzanol.

Gastrointestinal effects

Gamma oryzanol has been used to treat GI problems. The mechanisms by which gamma oryzanol exerts its effects appear to be the normalizaton of nervous system control of digestive secretion.

Bodybuilding

Gamma oryzanol also is used as a supplement in bodybuilding, but few well controlled human trials exist indicating any benefits.

Other uses

Gamma oryzanol's effects on the CNS and endocrine system have been sporadically reported. Animal studies show that gamma oryzanol increases brain norepinephrine content. In humans, gamma oryzanol inhibits TSH levels in patients with hypothyroidism, possibly by a direct action at the hypothalamus. The overall importance of these effects requires more clinical trials.

What is the dosage of Gamma Oryzanol?

Gamma oryzanol was studied for improvement in exercise training at a daily dose of 500 mg/day. It also has been used topically.

Is Gamma Oryzanol safe?

Contraindications

Contraindications have not yet been identified.

Pregnancy/nursing

Information regarding safety and efficacy in pregnancy and lactation is lacking.

Interactions

None well documented.

Side Effects

Research reveals little or no information regarding adverse reactions with the use of this product.

Toxicities

Not known to be mutagenic (causing mutations), clastogenic (causes breaks in chromosomes), or carcinogenic (causing cancer).

References

1. Gamma Oryzanol. Review of Natural Products. factsandcomparisons4.0 [online]. 2005. Available from Wolters Kluwer Health, Inc. Accessed April 16, 2007.