Brown Rice (Oryza sativa): Health benefits and Side effects

Introduction

For centuries, Rice (Oryza sativa L.) belongs to the family Poaceae is a staple food for many people. The high demand makes rice one of the largest producing crops around the world. Nowadays the advance of grain-processing technology made it possible for large scale production. Today there are more than 8000 varieties of rice (1).

What is Brown Rice?

Rice can be group as either white or brown rice depending upon the post-harvesting process.

White rice

It is also known as polished rice is manufactured by removing the outer bran and germ layer consist of starchy endosperm.

Brown rice

In brown rice, the outer bran is not removed therefore called unpolished rice. Brown rice is further divided into germinated and non-germinated brown rice. Germinated rice is made by soaking the brown rice grain in water to initiate germination.

Nutritional value of Brown Rice

According to the United States Department of Agriculture (USDA), Brown Rice contains a relatively high amount of dietary fibers, phytic acid and B vitamins, and γ-aminobutyric acid (GABA), and other components are as follows (2).

Health benefits of Brown Rice

1. Manage diabetes

Brown rice helps in decreasing the risk of developing Type 2 diabetes (3). The High phytic acid, polyphenols, dietary fiber helps in lowering the glycemic index by slowing glucose absorption and improves insulin sensitivity (4).

2. Antioxidant activity

It contains vitamin E, phenolic acid, and antioxidant enzymes such as superoxide dismutase and glutathione peroxidase. All these compounds in the brown rice help in reducing the risk of various diseases by protecting cells against oxidative damage (5).

3. Sleep-inducing

Brown rice contains tryptophan which encourages the production of serotonin. Serotonin has sedative and analgesic properties (6).

Moreover germinated brown rice contains GABA (neurotransmitter) which significantly improves sleep quality among elderly people which may help with insomnia.

4. Prevent Alzheimer’s disease

Germinated brown rice contains a potent inhibitor which facilitates the slowdown of an enzyme called protylendopetidase, which causes Alzheimer’s disease and other dementias (7).

5. Prevent  obesity

A research study suggested that brown rice decreases body weight because it contains high fiber. It helps in controlling the appetite by delaying carbohydrate absorption. Fibers also help in lowering the glycemic index and postprandial glucose and insulin levels which reduce hunger or increase satiety further reduce BMI and waist circumference in metabolic syndrome patients (8).  

6. Lowers cholesterol

g-Oryzanol found in brown rice is responsible for decreasing serum triglycerides (TGs) and total cholesterol (TC) levels and increasing high-density lipoprotein (HDL) cholesterol levels. Therefore, brown rice supplementations on diet suppress lipid accumulation and improve serum lipid profiles (9).

7. Good for lactating mothers

Consumption of brown rice is good for lactating mothers’ mental health because it may reduce depression, anger-hostility, and fatigue thus a significant decrease in total mood disturbance (10).

8. Improves digestion

Brown rice is good for the stomach because the bran layer on it contains nutrients that are more easily digested and it reduces the absorption of moisture and acid which cause texture degradation (11).

9. Healthy heart

Brown rice (195 g/day) is a rich source of insoluble fiber, magnesium, vitamin E, vitamin B1 and phytochemicals which keeps the heart healthy by improvements in endothelial function and preventing the formation of atherosclerotic plaques and lower risk of stroke (12).

10. Anti Cancerous

Brown rice contains biologically active compounds along with selenium which inhibits the inflammatory response in cancer (breast, colon, and prostate) through the reduction of oxidative stress (13). Moreover, GABA present in germinated brown rice also inhibits leukemia cell proliferation and promotes apoptosis of cancer cells (14).

11. Antidepressant

GABA, glutamine, and glycerin in germinated brown rice acts as an antidepressant and alleviate stress, anxiety, grief, or depression (15).

12. Healthy Liver

Selenium present in brown rice acts with the enzyme as a cofactor known as glutathione peroxidase. This helps in detoxify harmful molecules in the liver. Other compounds like detoxifying harmful molecules in the liver also help in decreasing liver inflammation and fibrosis and further reduce the risk of liver cirrhosis and cancer (16).

Chinese use brown rice congee (thin porridge) for the treatment of digestive diseases and helpful for the liver to recover naturally (17).

Side effects of Brown Rice

Brown rice is less popular than that of traditional white rice. This low popularity of brown rice is mainly due to its appearance, taste, longer cooking time, cost, limited availability, and bioavailability. Some of the side effects of brown rice are

1. Allergy

Allergy to brown rice is very rare because it is safe when consuming a moderate amount. But persons who have allergy from rice bran should avoid eating brown rice (18).

2. Presence of arsenic

Research study proved that brown rice contains 80 % more inorganic arsenic than white rice. This is mainly because of the presence of the germ layer in brown rice. Exposure to arsenic is bad for health (19). However, this risk can be reduced by cooking rice in high volumes of water and draining excess water (20).

3. Phytic acid in Brown rice

Brown rice also contains antinutrients like phytic acid that have adverse effects on the bioavailability of this whole-grain nutrient (21).

How to cook brown rice?

Brown rice takes a long time and a high volume of water than white rice because of its outer layer. For 1 cup soaked brown rice to 2 cups of water (500 mL) is required. It takes approximately 25- 30 min. And should be consumed within 24 hrs of its cooking (22).

Brown rice pilaf recipe

Ingredients for 2 persons

1. Brown rice 1 cup
2. Green vegetables (carrot, bell pepper, zucchini, broccoli)
3. Butter or oil
4. Cinnamon
5. Cardamom (Black and green)
6. Clove
7. Bay leaf
8. Water
9. Salt and pepper

Method

1. Cook brown rice (for one cup brown rice add 2 and a half cup of water) for at least half an hour.
2. Boil vegetables (5 mins maximum) and keep them aside.
3. In a pan and add little oil or butter and heat it. Then add cinnamon, cardamon (1 black), clove, and fry it.
4. Add onion and vegetables and saute it.
5. Add the boiled brown rice and mix it well
6. Reduce the heat and simmer for 10 to 15 min and ready to serve

Edited By Dr. Asha Jyoti Bharati