By: Laura Aldama
What if I told you that brown rice may actually be dangerous to your health? When it comes to rice, we often think of brown rice as the more nutritious option compared to white rice. Unfortunately, brown rice has been found to have unsafe levels of inorganic arsenic, specifically brown rice that is grown in the United States. The good news is that we don’t have to give up brown rice completely. There are ways that we can enjoy brown rice without increasing our exposure to inorganic arsenic. But first, let’s answer some questions you may have about inorganic arsenic in brown rice.
What’s the problem with arsenic?
Organic arsenic is a less harmful form of arsenic, but inorganic arsenic is a heavy metal and is classified as a class 1 carcinogen by the International Agency for Research on Cancer (IARC).1 Inorganic arsenic can be found in the water, soil, and food such as poultry, seafood, mushrooms, and rice.2 Inorganic arsenic can induce oxidative stress, leading to accumulation of free radicals, thus damaging cells and DNA, ultimately leading to various cancers, as well as increasing the risk of developing cardiovascular disease, diabetes, and neurological disorders.2,3
How does inorganic arsenic get into brown rice?
Chickens are fed arsenic-based drugs to combat disease, stimulate growth, and improve pigmentation.4 When the chickens consume the arsenic containing drugs, the arsenic then shows up in their feces. The feces are then used as a fertilizer for rice paddies. The arsenic gets into the soil, and ultimately into the rice we consume.4 Even though the use of arsenic-based drugs has been banned, arsenic residues remain in the soil, and unfortunately, rice absorbs arsenic more easily than other crops. Arsenic-based pesticides were also used on the cotton fields of the South, where rice is now grown today.5 The good news is that not all rice is high in arsenic.
What types of rice have the least amount of arsenic?
The amount of arsenic in rice depends on the type of rice (e.g. short vs. long grain, brown vs. white rice) and geographic location where it is grown. In general, short grain rice has less arsenic than long grain rice. Rice that is grown in California, Pakistan, India, and Thailand have lower arsenic levels than rice that is grown in the southern U.S.5 Brown rice tends to have more inorganic arsenic than white rice because arsenic builds up on the outer layer of the grain, which is removed to produce white rice.6 A potential alternative solution is to buy organic rice. However, organic rice was also found to have high arsenic levels just like conventional rice.7 When it comes to specific brands, Lundberg is a brand that ensures low levels of arsenic in their brown rice by testing the arsenic levels in their rice and publishing those test results on their website. Furthermore, although brown rice has more arsenic than white rice, Wu and colleagues6 found that there was no difference found in the urine arsenic levels of those who ate brown rice versus white rice. The reason for this is because the arsenic in brown rice appears to be less bioavailable than in white rice. However, a limitation to this study was the small sample size of brown rice eaters.6
Cooking method to reduce arsenic levels in rice
The good news is that there is a cooking method that can help reduce the arsenic in rice. Rinsing brown or white rice, and then cooking with more water, like cooking pasta, helps to reduce the arsenic in half.8 The optimal ratio of water to rice that can effectively reduce the arsenic is 6:1.8 Simply boil the rice with 6 cups water to 1 cup rice, and drain the excess water. However, one concern with this cooking method is the potential loss of nutrients in the excess water. Gray et al.9 found that cooking brown rice in excess water reduces arsenic levels by 50%, but the iron, folate, niacin, and thiamin losses were significantly less than the 50-70% loss of the same nutrients from enriched white rice. This is because white rice is enriched with vitamins and minerals that are sprayed on it, and then get washed off when rinsing or cooking with a lot of water. On the other hand, brown rice is not enriched, so the nutrients are protected because they are inside the grain rather than sprayed on.9 Therefore, if you want to retain most of the nutrients in the rice, it might be better to choose brown rice.
Antioxidants and arsenic
In addition to boiling rice to reduce arsenic levels, antioxidants play a major role in combating the damaging effects of arsenic. Turmeric is a spice that contains curcumin, which is a powerful antioxidant. Curcumin was found to scavenge free radicals, act as a chelating agent, and reduce the damage to the DNA repair enzyme that was damaged by arsenic.10,11 Consuming a diet rich in antioxidants such as turmeric, may help to effectively reduce the oxidative damage caused by inorganic arsenic in rice.
Other Solutions
Another way to prevent consuming too much arsenic in rice is to ensure that the type of rice you choose has lower levels of arsenic or to choose other grains. If rice is a staple in your diet, there are ways to ensure you are not consuming an excess amount of arsenic. First, you can check where your rice was grown. Second, you can cook your rice with a water to rice ratio of 6:1. Lastly, you can add more variety to your diet by exploring other types of grains. Grains such as quinoa, bulgur, barley, and farro were found to have much lower levels of arsenic compared to rice.7
Curried Rice Recipe
Ingredients
For the curried rice
1.5 cups basmati rice uncooked
2 Tbsp olive oil
4 Tbsp curry powder
4 cloves garlic
1 cup onions, diced
1/4 cup coconut milk
1/2 cup chopped carrots
1/2 cup peas
3 cups vegetable broth
salt, pepper to taste
For the toasted cashews
1/3 cup cashews
1 tsp curry powder
1 tsp olive oil
salt, pepper to taste
Start out with cooking the rice. Instead of water, cook it in vegetable broth. Reduce the cooking time from the package directions by about 2 minutes.*
While the rice is cooking, heat 2 Tbsp of olive oil in a saucepan or casserole. Add diced onion and garlic and fry for about 5 minutes on medium heat. Then add carrots and peas, and season with salt and pepper. Reduce heat and let it simmer.
By now your rice should be done. Drain the rice. Add coconut milk and curry powder and mix well.
Transfer the fried vegetables to the rice and combine well.
Heat 1 tsp olive oil, add cashews and curry powder. Season with a pinch of salt and pepper and toast them for around 5 minutes until lightly browned.
Garnish the Curried Rice with toasted cashews and serve rice on plates or in bowls.
*Note: If using the 6:1 water to rice cooking method, use 6 ½ cups instead of the vegetable broth. Bring the water to a boil and add the rice. Once the rice is cooked, drain the excess water.
References
1. Kim HS, Kim YJ, Seo YR. An Overview of Carcinogenic Heavy Metal: Molecular Toxicity Mechanism and Prevention. Journal of Cancer Prevention. 2015; 20(4):232-240. doi:10.15430/jcp.2015.20.4.232.
2. Jomova K, Jenisova Z, Feszterova M, et al. Arsenic: toxicity, oxidative stress and human disease. J Appl Toxicol. 2011;31(2):95-107. doi:10.1002/jat.1649
3. Oberoi S, Barchowsky A, Wu F. The global burden of disease for skin, lung and bladder cancer caused by arsenic in food. Cancer Epidemiol Biomarkers Prev. 2014; 23(7):1187-1194. doi:10.1158/1055-9965.EPI-13-1317.
4. Yao L, Huang L, He Z, Zhou C, Lu W, Bai C. Delivery of roxarsone via chicken diet → chicken → chicken manure → soil → rice plant. Science of The Total Environment. 2016;566-567:1152-1158. doi:10.1016/j.scitotenv.2016.05.157.
5. Potera C. U.S. rice serves up arsenic. Environ Health Perspect. 2007;115(6):A296. doi:10.1289/ehp.115-a296
6. Wu H, Grandjean P, Hu FB, Sun Q. Consumption of White Rice and Brown Rice and Urinary Inorganic Arsenic Concentration. Epidemiology. 2015;26(6). doi:10.1097/ede.0000000000000369.
7. Consumer Reports. How Much Arsenic Is in Your Rice? Consumer Reports. https://www.consumerreports.org/cro/magazine/2015/01/how-much-arsenic-is-in-your-rice/index.htm. Published November 18, 2014. Accessed January 17, 2021.
8. Naito S, Matsumoto E, Shindoh K, Nishimura T. Effects of polishing, cooking, and storing on total arsenic and arsenic species concentrations in rice cultivated in Japan. Food Chemistry. 2015;168:294-301. doi:10.1016/j.foodchem.2014.07.060.
9. Gray PJ, Conklin SD, Todorov TI, Kasko SM. Cooking rice in excess water reduces both arsenic and enriched vitamins in the cooked grain. Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2016;33(1):78-85.
10. García-Niño WR, Pedraza-Chaverrí J. Protective effect of curcumin against heavy metals-induced liver damage. Food and Chemical Toxicology. 2014;69:182-201. doi:10.1016/j.fct.2014.04.016.
11. Roy M, Sinha D, Mukherjee S, Biswas J. Curcumin prevents DNA damage and enhances the repair potential in a chronically arsenic-exposed human population in West Bengal, India. European Journal of Cancer Prevention. 2011;20(2):123-131. doi:10.1097/cej.0b013e328341017a.
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