What are some strategies to reduce arsenic exposure from rice?
Those who are exposed to the most arsenic in rice are those who are exposed to the most rice, like people who are eating plant-based, gluten-free, or dairy-free. So, at-risk populations are not just infants and pregnant women, but also those who may tend to eat more rice. What “a terrible irony for the health conscious” who are trying to avoid dairy and eat lots of whole foods and brown rice—so much so they may not only suffer some theoretical increased lifetime cancer risk, but they may actually suffer arsenic poisoning. For example, a 39-year-old woman had celiac disease, so she had to avoid wheat, barley, and rye, but she turned to so much rice that she ended up with sky-high arsenic levels and some typical symptoms, including “diarrhea, headache, insomnia, loss of appetite, abnormal taste, and impaired short-term memory and concentration.” As I discuss in my video How Much Arsenic in Rice Is Too Much, we, as doctors, should keep an eye out for signs of arsenic exposure in those who eat lots of rice day in and day out.
As you can see at 1:08 in my video, in its 2012 arsenic-in-rice exposé, Consumer Reports recommended adults eat no more than an average of two servings of rice a week or three servings a week of rice cereal or rice pasta. In its later analysis, however, it looked like “rice cereal and rice pasta can have much more inorganic arsenic—a carcinogen—than [its] 2012 data showed,” so Consumer Reports dropped its recommendation down to from three weekly servings to a maximum of only two, and that’s only if you’re not getting arsenic from other rice sources. As you can see from 1:29 in my video, Consumer Reports came up with a point system so people could add up all their rice products for the week to make sure they’re staying under seven points a week on average. So, if your only source of rice is just rice, for example, then it recommends no more than one or two servings for the whole week. I recommend 21 servings of whole grains a week in my Daily Dozen, though, so what to do? Get to know sorghum, quinoa, buckwheat, millet, oatmeal, barley, or any of the other dozen or so common non-rice whole grains out there. They tend to have negligible levels of toxic arsenic.
Rice accumulates ten times more arsenic than other grains, which helps explain why the arsenic levels in urine samples of those who eat rice tend to consistently be higher than those who do not eat rice, as you can see at 2:18 in my video. The FDA recently tested a few dozen quinoa samples, and most had arsenic levels below the level of detection, or just trace amounts, including the red quinoas that are my family’s favorite, which I was happy about. There were, however, still a few that were up around half that of rice. But, overall, quinoa averaged ten times less toxic arsenic than rice. So, instead of two servings a week, following the Consumer Reports recommendation, you could have 20. You can see the chart detailing the quinoa samples and their arsenic levels at 2:20 in my video.
So, diversifying the diet is the number-one strategy to reduce exposure of arsenic in rice. We can also consider alternatives to rice, especially for infants, and minimize our exposure by cooking rice like pasta with plenty of extra water. We found that a 10:1 water-to-rice ratio seemed best, though the data suggest the rinsing doesn’t seem to do much. We can also avoid processed foods sweetened with brown rice syrup. Is there anything else we can do at the dining room table while waiting for federal agencies to establish some regulatory limits?
What if you eat a lot of fiber-containing foods with your rice? Might that help bind some of the arsenic? Apparently not. In one study, the presence of fat did seem to have an effect, but in the wrong direction: Fat increased estimates of arsenic absorption, likely due to the extra bile we release when we eat fatty foods.
We know that the tannic acid in coffee and especially in tea can reduce iron absorption, which is why I recommend not drinking tea with meals, but might it also decrease arsenic absorption? Yes, by perhaps 40 percent or more, so the researchers suggested tannic acid might help, but they used mega doses—17 cups of tea worth or that found in 34 cups of coffee—so it isn’t really practical.
What do the experts suggest? Well, arsenic levels are lower in rice from certain regions, like California and parts of India, so why not blend that with some of the higher arsenic rice to even things out for everybody?
Another wonky, thinking-outside-the-rice-box idea involves an algae discovered in the hot springs of Yellowstone National Park with an enzyme that can volatize arsenic into a gas. Aha! Researchers genetically engineered that gene into a rice plant and were able to get a little arsenic gas off of it, but the rice industry is hesitant. “Posed with a choice between [genetically engineered] rice and rice with arsenic in it, consumers may decide they just aren’t going to eat any rice” at all.
This is the corresponding article to the 11th in a 13-video series on arsenic in the food supply. If you missed any of the first ten videos, watch them here:
You may also be interested in Benefits of Turmeric for Arsenic Exposure.
Only two major questions remain: Should we moderate our intake of white rice or should we minimize it? And, are there unique benefits to brown rice that would justify keeping it in our diet despite the arsenic content? I cover these issues in the final two videos: Is White Rice a Yellow-Light or Red-Light Food? and Do the Pros of Brown Rice Outweigh the Cons of Arsenic?.
Michael Greger, M.D.
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