Does rice bran have gamma-oryzanol?

January 11, 2026 •

3 min read

Gamma-oryzanol was first isolated from rice bran oil by researchers in the mid-1950s and has been used therapeutically in Japan since the 1960s. As a valuable phytochemical, its presence in rice bran is well-documented and forms the basis for numerous supplements and health products worldwide.

Quick Summary

Rice bran is a rich source of gamma-oryzanol, a potent mixture of antioxidant compounds beneficial for health. This valuable bioactive is concentrated in the bran layer and can be extracted for use in functional foods and supplements.

Key Points

Source of Antioxidants: Rice bran is confirmed to contain gamma-oryzanol, a mixture of strong antioxidant compounds.
Cholesterol Management: Gamma-oryzanol helps lower bad LDL cholesterol by blocking its absorption, contributing to cardiovascular health.
Processing Matters: The amount of gamma-oryzanol is highest in crude rice bran oil and significantly decreases with chemical refining.
Bran vs. Germ: Rice bran contains substantially more gamma-oryzanol than rice germ, making it the superior source.
Versatile Uses: Gamma-oryzanol is extracted for various applications, including health supplements, skin care, and functional foods.
Anti-inflammatory Action: Studies indicate that gamma-oryzanol has anti-inflammatory properties, providing broader health benefits beyond antioxidants.
Natural Compound: This phytochemical is a naturally occurring component of the outer layer of the rice kernel.

Yes, Rice Bran is a Primary Source of Gamma-Oryzanol

Rice bran is indeed a significant natural source of gamma-oryzanol. Gamma-oryzanol is a blend of ferulic acid esters of sterols and triterpene alcohols, which act as natural antioxidants. These compounds are most abundant in the crude oil extracted from the bran layer. {Link: Drugs.com https://www.drugs.com/npp/gamma-oryzanol.html}.

Potential Health Benefits of Gamma-Oryzanol

The gamma-oryzanol in rice bran has been linked to several health advantages:

Cholesterol Management: It may help lower LDL cholesterol by reducing its absorption in the intestines.
Antioxidant Activity: As a strong antioxidant, it helps protect cells from damage caused by free radicals.
Anti-inflammatory Effects: Research suggests gamma-oryzanol possesses anti-inflammatory properties.
Menopausal Symptom Relief: Historically used in Japan for menopausal symptoms, further research is ongoing.
Skin Health: Its antioxidant and anti-inflammatory qualities make it useful in cosmetic applications for skin protection.

Concentration and Extraction Methods

The concentration of gamma-oryzanol varies based on factors like rice variety and processing. The bran layer contains a higher concentration than other parts of the rice kernel.

Key methods for extracting gamma-oryzanol include:

Solvent Extraction: Organic solvents are used to extract crude rice bran oil containing gamma-oryzanol.
Supercritical Fluid Extraction (SFE): This method uses supercritical CO2, often yielding higher purity and quantity of gamma-oryzanol compared to solvent extraction.
Physical Refining: This process aims to retain more gamma-oryzanol in the oil compared to chemical refining.

Comparison: Rice Bran vs. Rice Germ Gamma-Oryzanol Content

Studies indicate rice germ contains about five times less gamma-oryzanol than rice bran.


Feature	Rice Bran	Rice Germ
Primary Location on Grain	Outer bran layer	Embryo/Germ
Gamma-Oryzanol Content	High concentration	Low concentration (approx. 5x less)
Other Noteworthy Phytochemicals	Tocotrienols, phytic acid	Alpha-tocopherol, gamma-tocopherol
Primary Extraction Product	Rice Bran Oil	Oil and protein isolates

Commercial Applications

Gamma-oryzanol is utilized in nutraceuticals, functional foods, and cosmetics. It's available as a supplement derived from rice bran oil and used in various products, including cooking oils, skincare, and dietary supplements. The National Institutes of Health (NIH) provides further scientific information on gamma-oryzanol.

Conclusion

Rice bran is a confirmed and significant natural source of gamma-oryzanol. This powerful antioxidant offers potential benefits, particularly for cholesterol management, skin health, and reducing inflammation. The highest concentration is found in the raw bran and crude oil, but refining methods can impact its presence. Modern extraction techniques allow for its isolation and use in a variety of products, from dietary supplements to cosmetics. Consumers should consider the processing method of rice bran products to understand their potential gamma-oryzanol content.

Key Takeaways

Presence Confirmed: Yes, rice bran contains gamma-oryzanol, a mixture of ferulic acid esters.
Key Antioxidant: Gamma-oryzanol is a potent antioxidant that helps combat oxidative stress.
Cardiovascular Benefits: It aids in lowering LDL ("bad") cholesterol levels by inhibiting its intestinal absorption.
Higher Concentration in Bran: The bran layer has a significantly higher concentration of gamma-oryzanol compared to the rice germ.
Refining Affects Content: Chemical refining processes can drastically reduce gamma-oryzanol levels in the final oil product.
Used in Supplements: Due to its health benefits, gamma-oryzanol is widely extracted from rice bran oil for use in dietary supplements.
Anti-inflammatory Effects: It possesses anti-inflammatory properties that may benefit conditions associated with chronic inflammation.

Frequently Asked Questions

Gamma-oryzanol is a group of ferulic acid esters of phytosterols and triterpene alcohols found naturally in rice bran oil. It is a powerful antioxidant and has been studied for various health-promoting properties.

Gamma-oryzanol is considered possibly safe for most adults when taken orally or applied to the skin in normal dosages. However, individuals with thyroid issues, pregnant or breastfeeding women should avoid its use, and it is always best to consult a healthcare provider.

Gamma-oryzanol is believed to help lower cholesterol by reducing the absorption of dietary cholesterol in the digestive tract. This action primarily helps decrease total and LDL cholesterol levels.

Gamma-oryzanol is primarily concentrated in the bran layer of the rice grain. This is the outer, brown portion that is removed during the milling process to produce white rice.

Extraction can be done using organic solvents like hexane or more advanced, environmentally friendly techniques such as supercritical fluid extraction (SFE). The gamma-oryzanol is first extracted into oil and then further purified.

Yes, refining significantly impacts the content. While crude rice bran oil has a high concentration, the chemical refining process can remove over 90% of the gamma-oryzanol. Physical refining methods tend to preserve more of it.

To achieve therapeutic dosages of gamma-oryzanol, supplementation is usually necessary. While eating brown rice or using unrefined rice bran oil provides some, the high potency often requires a concentrated supplement.