Research Proven Health Benefits of Oryza Gammax®

1) Reduce cholesterol & triglycerides

Numerous studies have supported the role of gamma oryzanol in reducing total cholesterol, LDL (bad) cholesterol and triglycerides levels, and increasing HDL (good) cholesterol in persons with high cholesterol levels. It might help reduce cholesterol levels by reducing the absorption of cholesterol from foods, increasing conversion of cholesterol to bile acids and excretion of bile acids.

Study 1:

In this clinical trial, 40 females aged 38-62 years old were orally administered a total of 300mg gamma oryzanol daily at 3 separate times for 4 to 8 weeks. For those with hyperlipidemia (total cholesterol ≥ 220 mg/dl, triglycerides ≥ 140 mg/dl, HDL-cholesterol ≤ 45 mg/dl), results showed significantly reduced total cholesterol and triglycerides levels and increased HDL-cholesterol, with no side effects observed. In short, gamma oryzanol improved blood lipid profile and could potentially reduce the risk of cardiovascular diseases.

2) Protect against oxidation of blood lipids

Gamma oryzanol is one of the chain-breaking antioxidants. Both sterol and phenolic hydroxyl groups in the gamma oryzanol may be responsible for its antioxidant function. An in vitro study found that gamma oryzanol was more than 4 times as effective as Vitamin E in preventing tissue oxidation. The cholesterol-lowering property of gamma oryzanol may be attributed to its antioxidant function against cholesterol oxidation.

Study 1:

Hydroperoxide is an unstable intermediate of lipid peroxidation by-products formed as a result of oxidation of cholesterol or polyunsaturated fatty acids, through either nonradical or radical mechanisms. In this study, various concentrations of gamma oryzanol were found to provide antioxidant protection, as measured by the formation of hydroperoxides. In addition, gamma oryzanol was observed to be a more effective antioxidant than  synthetic antioxidants in preventing the formation of hydroperoxide.

Study 2:

In this study, gamma oryzanol was shown to suppress lipid oxidation in lard, suggesting its antioxidative property.

Study 3:

Subjects with high blood lipids were orally administered gamma oryzanol for 12 weeks. Results showed gamma oryzanol significantly reduced lipid peroxide levels in the blood serum after 8 weeks and this effect was sustained for another 2 weeks after the administration has stopped.

3) Support healthy blood vessels

Fatty streaks are the first visible sign of atherosclerosis (build-up of fatty deposits) in the arteries. They consist of cholesterol, white blood cells and other cellular matter in the arterial wall. These lesions could occur in the aorta and other arteries of most people by age 20. Over time, fatty streaks can evolve into atherosclerotic plaques, which can restrict blood flow.

In this test, two groups of subjects were fed chow-based diets containing 0.05% cholesterol and 10% coconut oil (control) and the control diet plus 0.5% gamma oryzanol respectively. Compared to the control group, subjects treated with gamma oryzanol showed reduced total cholesterol by 44%, non-HDL-cholesterol by 57% and triglyceride by 46%. In addition, the fatty streak formation in the aorta was significantly reduced 67% (p < 0.01) in subjects treated with gamma oryzanol. In conclusion, the cholesterol-lowering activity of gamma oryzanol was associated with significant reductions in aortic fatty streak formation (Lipids. 32(3): 303-309 (1997)).

4) Maintain healthy glucose levels

In this test, diabetic subjects were administered 50 mg/kg of gamma oryzanol daily. Results showed single-dose and multiple-dose administration remarkably reduced the blood glucose levels of diabetic subjects. In addition, oxidative stress produced by diabetes was found to be significantly reduced by gamma oryzanol, as evident from a significant decrease in the extent of lipid peroxidation (LPO) and increased levels of enzymatic antioxidants, such as superoxide dismutase (SOD) and reduced glutathione (GSH) in the liver. These findings suggest that gamma oryzanol has the potential to effectively reduce blood glucose levels and reduce the oxidative stress induced by diabetes. 

5) Suppress harmful clot formation

Harmful blood clots are formed when platelets accumulate and clump together, this can cause blockage in the blood vessels and if not rectified, can lead to a heart attack or stroke.

In this test, subjects were administered gamma oryzanol in a 1% cholesterol diet (HCD) or control diet. Gamma oryzanol fed along with cholesterol diet (HCD) significantly suppressed platelet aggregation induced by ADP (Adenosine Diphosphate) and totally suppressed aggregation induced by collagen. On the other hand, gamma oryzanol with the control diet did not change platelet aggregation induced by ADP and collagen.

6) Improve metabolic health

Metabolic refers to the whole range of biochemical processes involved in the normal functioning of the body. Metabolic syndrome refers to a group of risk factors that increase the risk of cardiovascular disease, stroke, diabetes and diseases linked to fatty build-ups in artery wall. This severe health condition affects around 23% of adults.  The underlying causes of metabolic syndrome include obesity, a sedentary lifestyle, genetic factors and ageing. To target metabolic syndrome, brain dysfunction such as dependence on animal fat should be addressed.

In this test, subjects were fed with excessive animal fat to evoke the endoplasmic reticulum (ER) stress in the brain hypothalamus, inducing great preference for animal fat intake. Results showed that administration of gamma oryzanol decreased ER stress in the hypothalamic area and alleviated animal fat dependence and animal fat-rich diet-induced high blood glucose. In a crossover clinical trial targeting middle-aged patients with metabolic syndrome, the intake of gamma oryzanol-rich fermented beverage also decreased the preference for animal fat-rich diet, improved the imbalanced gut microbiota, chronic constipation and skin conditions. These findings suggest the beneficial effects of gamma oryzanol in supporting optimal metabolic health.

7) Reduce the risk of fatty liver

Dietary cholesterol intake has been identified as a factor related to the risk and severity of non-alcoholic fatty liver disease (NAFLD).

Test subjects were administered a high calorie diet (HCD) or HCD + gamma oryzanol for 13 weeks. Compared to the control (HCD), gamma oryzanol suppressed the increment of liver weight caused by a HCD, suggesting the protective effect of gamma oryzanol against fatty liver.

8) Improve nervous system

i) Dysautonomia:

Dysautonomia is a condition in which the autonomic nervous system does not work properly. The autonomic nervous system controls the body functions such as heart rate, blood pressure, digestion, kidney function and temperature control.  Individuals with dysautonomia have difficulty regulating these systems and have to live with abnormal heart rates, unstable blood pressure, dizziness, fainting spells, malnutrition and in serious cases, death. Currently, there is no cure for any form of dysautonomia.

Gamma oryzanol was reported to improve the condition of post-traumatic dysautonomia from head injuries, with no side effects reported at large dosage. In this clinical trial, 31 dysautonomia patients (12 males, 19 females) aged between 14 and 52 years old were orally administered a total of 45 mg gamma oryzanol daily at 3 separate times for 21 days. Results showed that 74% of dysautonomia condition was improved, suggesting the beneficial effects of gamma oryzanol on the nervous system.

ii) Gynaecological autonomic nervous system

Gamma oryzanol is beneficial to middle-aged and menopausal neuropathy, which is a damage or dysfunction of one or more nerves. It commonly results in numbness, tingling sensations, muscle weakness and pain in the hands, feet and other parts of the body.  In addition, gamma oryzanol also supports healthy nervous system on women undergoing hysterectomy (an surgery to remove the uterus).

9) Improve menopausal symptoms

A number of clinical studies have proven that Gamma oryzanol is effective in relieving menopausal (climacteric) symptoms. Approximately 67-85% menopausal women and women whose ovaries were surgically removed experienced a significant reduction in menopausal symptoms with treatment of gamma oryzanol (Chem Parm Bull. 30(3): 973-979 (1982), Murray, M. (1996): Encyclopedia of Nutritional Supplements. Prima Publishing, pp. 332-335).

In this clinical trial, 40 females (aged 38 – 62) who were suffering from menopausal symptoms were orally administered a total of 300 mg gamma oryzanol per day at 3 separate times, for 4 to 8 weeks. The severity of menopausal complaints was measured using the Kupperman Index and a questionnaire. Results showed remarkable improvement in 90% of the menopausal symptoms, with no known side effects. A subjective symptom of a climacteric (menopause) disturbance was recovered 85%, suggesting the beneficial effects of gamma oryzanol on menopausal women.


Vasomotor complaints: Examples are night sweats, hot flashes, and flushes

Paresthesia: burning or prickling sensation in hands, arms, legs, feet etc.

Insomnia: sleep disorder which includes trouble falling and / or staying asleep

Melancholia: a feeling of deep sadness

Vertigo: a sense of spinning dizziness

Arthralgia: joint pain

Myalgia: muscle pain

Palpitation: feelings of having a fast-beating, fluttering or pounding heart

Formication: feeling of insects crawling across or underneath skin

Research showed that as estrogen levels increase during a woman’s menstrual cycle, HDL (good) cholesterol levels increase and LDL (bad) cholesterol levels decrease as well. During menopause, the decrease of blood estrogen levels leads to an increase in blood cholesterol and development of atherosclerosis (hardening of arteries) in menopausal women. This is because cholesterol is not effectively removed from the blood as the number of low-density lipoprotein cholesterol receptors on body cells increased due to the change in estrogen levels.

In this study, menopausal women were found to have significantly higher lipid peroxidation and administration of gamma oryzanol significantly reduced lipid peroxidation in the blood serum. These findings suggest the cardioprotective benefits of gamma oryzanol for menopausal woman.

10) Improve muscle strength

In a double-blind clinical trial, 30 healthy males (aged 18 to 32) was orally administered 600 mg of gamma-oryzanol or placebo (lactose) after 9 weeks of training. The exercise involved was 80% 1-Repetition Maximum (1-RM), for 1 hour and 4 days/week. Their muscle strength (bench press and leg curl) was determined at the commencement and end of the 9-week study.

There were significant differences between the muscle strength of the gamma oryzanol and placebo groups. Oral administration of 600 mg/day of gamma oryzanol for 9 weeks significantly improved muscle strength following the resistance training. These findings supported the efficacy of gamma oryzanol in improving sport performance of athletes.

11) Improve gastrointestinal health

Gamma oryzanol has therapeutic potential for numerous gastrointestinal diseases, including gastric ulcers and colon inflammation.

Study 1: In a test, gamma oryzanol was shown to suppress histamine- and tetragastrin-stimulated gastric secretion and experimental ulcers in subjects. The suppressive effect of gamma oryzanol on gastric secretion was proposed to be mediated by the vagus nerve, which plays a role in the action of gastrin, a hormone that stimulates the secretion of gastric acid (Nihon Yakurigaku Zasshi. 74(2):285-295 (1978)).


Study 2: In another test, experimental colitis was induced in subjects by 1% DSS (dextran sulphate sodium) in drinking water for 16 days with or without 50mg/kg/day gamma oryzanol. Gamma oryzanol was found to improve DSS-induced colon inflammation. This improvement was associated with the suppression of myeloperoxidase (MPO) activity (inflammation marker), decreased production of cytokines such IL-1β, TNF-α, and IL-6, and inhibition of COX-2 and NF-κB activity in colitis tissue. In addition, in vitro assay demonstrated that gamma oryzanol has strong antioxidant effects comparable to those of α-tocopherol. These findings suggested the beneficial effects of gamma oryzanol for treatment of gastrointestinal complaints.

12) Stimulate immune system & suppress abnormal cell growth

Multiple components of gamma oryzanol – cycloartenyl ferulate, 24-methylene cycloartanyl ferulate, campesteryl ferulate and sitosteryl ferulate were reported to have inhibitory effects on abnormal growth.

In this test, subjects which were fed standard diets supplemented with gamma oryzanol for 2 weeks were inoculated with colon cancer cells and fed the same diet for 2 additional weeks.

Tumour weight was found to be significantly lower in the gamma oryzanol group, compared to control. Inhibitory effects of gamma oryzanol on tumour regression is attributed to activation of immune system and reduction in the number of blood vessels inside the tumour.

13) Support healthy brain function

Brain inflammation has been suggested as an important factor that contributes and aggravates cognitive decline among the elderly. The antioxidant and anti-inflammatory properties of gamma oryzanol has been demonstrated to cross the blood-brain barrier intact and exert beneficial effects on brain function.

Subjects were orally administered 100 mg/kg gamma oryzanol or control daily for 21 days and then exposed to an inflammatory stimulus elicited by lipopolysaccharide (LPS). Results showed that gamma oryzanol improved cognitive performance during the brain inflammatory response. In addition, gamma oryzanol also upregulated antioxidant enzymes, such as heme oxygenase-1 (HO-1) and NADPH-dehydrogenase-quinone-1 (NQO1) in the hippocampus, a region of the brain associated with memory. Furthermore, gamma oryzanol showed a strong anti-inflammatory activity by downregulating inflammatory genes after LPS treatment. These findings suggest that long-term consumption of gamma oryzanol promotes antioxidant and anti-inflammatory responses, which could help reverse cognitive and memory impairments.

Note: This novel object recognition test was used to assess the effect of gamma oryzanol on long-term memory. Subject treated with LPS lost their ability to differentiate the new object from the familiar object, and indiscriminately explored both. On the other hand, mice pre-treated with gamma oryzanol and subsequently injected with LPS were able to distinguish the novel object, spending more time exploring it than the familiar one.

14) Support thyroid function

High thyroid-stimulating hormone (TSH) could mean the thyroid is not making sufficient thyroid hormones, a condition known as hypothyroidism.

In this clinical trial, a single 300 mg dose of gamma oryzanol produced a significant reduction on the elevated serum TSH level in hypothyroid patients. Similarly, chronic treatment with a daily dose of 300 mg gamma oryzanol for 7 days decreased serum TSH level in 6 of 8 patients, but it didn’t cause significant change to normal subjects. These findings suggest that gamma oryzanol suppresses serum TSH levels in patients with primary hypothyroidism, possibly by a direct action at the hypothalamus.

15) Support healthy kidneys

Obesity and metabolic syndrome are known to affect renal filtration, increasing the risk of chronic kidney disease. The antioxidant and anti-inflammatory activities of gamma oryzanol have shown a positive action in the treatment of obesity and metabolic diseases, which would potentially improve obesity-induced kidney injuries.

In this test, subjects were orally administered high sugar-fat diet (HSF) for 20 weeks. When proteinuria (protein in the urine) was detected, HSF subjects were allocated to receive gamma oryzanol or maintain HSF for more than 10 weeks. The effect of gamma oryzanol to recover renal function in obese subjects by HSF diet was evaluated.

Treatment with gamma oryzanol for 10 weeks resulted in improvement of inflammation, increased antioxidant enzyme activities and recovered renal function. These findings suggest that gamma oryzanol is able to modulate inflammation and oxidative stress pathways, improving obesity-induced renal disease.

16) Support fairer skin

Gamma oryzanol has been shown to have a potent and significant inhibitory effect on melanin formation.

In this in vitro study, B16F1 cells (melanin-producing cells) were treated with 3 and 30µM of gamma oryzanol. Gamma oryzanol significantly reduced melanin content in a dose-dependent manner. In addition, gamma oryzanol effectively reduced tyrosinase activity in a dose-dependent manner. Down regulation of tyrosinase activity has been proposed to be responsible for reduced melanin production. By reducing melanin production and tyrosinase activity, gamma oryzanol is effective in lightening skin tone.

17) Support healthy blood pressure

Rice bran, a by-product derived from processing rice, is a rich source of bioactive compounds, including gamma oryzanol. 

In this animal test, the efficacy of single and chronic supplementation of fermented rice bran for metabolic syndrome in stroke-probe spontaneously hypertensive rat (SHRSP) was evaluated. Results showed that single-dose administration of fermented rice bran (2 g/kg body weight) reduce systolic blood pressure, while chronic administration with 5% fermented rice bran for 4 weeks significantly reduced both systolic and diastolic blood pressure. In addition, rice bran supplementation improved leptin impairment and increased serum adiponectin levels and angiotensin-converting enzyme inhibitory activity. Furthermore, supplementation of fermented rice bran improved glucose tolerance and insulin sensitivity, serum insulin levels, as well as lipid profiles. In brief, dietary supplementation of fermented rice bran or possibly gamma oryzanol potentially helps reduce hypertension and alleviates metabolic syndrome.