Depends on age
By Jack Harrison, Michigan State University
.webp)
Whether you’re picking up rice at the grocery store or
ordering it as a side at a restaurant, you might choose brown rice over white
rice for its higher nutrient and fiber content. Many people associate brown
rice with healthier eating, but the reality is more complex.
Recent research from Michigan State
University, published in the journal Risk Analysis, found that
brown rice contains higher levels of arsenic, including inorganic arsenic,
compared to white rice in U.S. populations.
While these levels don’t pose significant health risks for
most adults, there may be concerns for infants and children under five, who eat
more relative to their body weight and may be more vulnerable to potential
exposure.
“This research is important because it acknowledges the importance of considering food safety along with nutrition when consumers make choices about food,” said senior investigator of the study Felicia Wu, John A. Hannah Distinguished Professor and University Distinguished Professor at MSU’s College of Agriculture and Natural Resources. “While we found that choosing brown rice over white rice would result in higher arsenic exposure on average, the levels should not cause long-term health problems unless someone ate an enormous amount of brown rice every day for years.”
Research background and methodology
Arsenic is a natural component of the earth’s crust, and it
is highly toxic. When compared to other cereal grains, rice has significantly
higher contents of arsenic. In fact, rice takes up nearly 10 times more arsenic
content than other grains.
This is because rice is often grown in continually flooded
paddies, and wet soil conditions favor arsenic being taken up from the soil
into the plants.
While the nutritional benefits of brown rice are well
documented, white rice remains to be consumed more both in the U.S. and
throughout the globe.
Therefore, Wu, along with postdoctoral research associate
and lead author Christian Scott, both in the Department of Food Science and
Human Nutrition, compared the arsenic exposure and associated risks between
brown and white rice for U.S. populations.
Specifically, after comparing the nutritional aspects of
brown and white rice, Wu and Scott used data courtesy of the “What We Eat in
America” database of the U.S. Environmental Protection Agency and Joint
Institute for Food Safety and Applied Nutrition to calculate average daily
intake mean rice values for both brown and white rice.
The results provided insight into the difference in arsenic
levels between brown and white rice as well as more complex data regarding how
levels differed by region, highlighting where and what populations may be at
increase health risk.
Geographic arsenic differences
The inorganic arsenic concentration of white versus brown
rice was considerably different by region. For rice grown in the United States,
the researchers found the proportion of the more toxic inorganic arsenic in
white rice was 33%, and in brown rice was 48%; whereas in rice grown globally,
53% of total arsenic in white rice was inorganic, 65% of total arsenic in brown
rice was inorganic. Organic arsenic, more commonly found in seafood as well as
in other foods, is less toxic because it is readily excreted from the body.
There are also some populations who are more vulnerable due
to elevated rice consumption or susceptibility to arsenic exposure.
Specifically, this includes young children, Asian immigrant populations, and
populations that face food insecurity.
The values researchers found did indicate a potential
harmful risk of arsenic exposure from brown rice for children under age 5 and
as young as 6 months.
Interpreting the results
It’s important to not interpret these findings as evidence
that brown rice is unhealthy, or that you should now consume only white rice,
Wu said. Brown rice does contain important ingredients such as fiber, protein,
and niacin, which all benefit consumers.
“This exposure assessment is only one side of the
equation when examining the potential trade-offs between brown and white rice
consumption,” Wu said. “Even if arsenic levels are slightly higher in brown
rice than white rice, more research is needed to demonstrate if the potential
risks from this exposure are mitigated in part by the potential nutritional
benefits provided by the rice bran.”
The researchers suggest completing an empirical analysis of
the cost and benefits to societal public health by consuming brown rice
compared to white rice. In their manuscript, they document additional key
differences between brown and white rice, including prices, overall nutritional
benefit, and environmental burden.
Potential policy changes
Chronic exposure to arsenic over a lifetime may increase
cancer risk. Therefore, this research raises the question about consumer
behavior and public health. If more consumers were aware about arsenic
concerns, then they may intentionally make different dietary decisions,
especially when it comes to rice consumption.
As water is already regulated, the Food and Drug
Administration’s Closer to Zero initiative will soon set action levels for
arsenic when it comes to food products based on risk assessment to the American
population. It is important for all consumers to be aware of arsenic levels in
their food and understand that brown rice is a major source.
As Americans try to eat healthily and look to incorporate
higher-nutrition content choices in their diets, this study challenges the
notion that these choices are simply black and white — or in this case, brown
and white.
Reference: “Arsenic content and exposure in brown rice
compared to white rice in the United States” by Christian Kelly Scott and
Felicia Wu, 28 February 2025, Risk Analysis.
DOI: 10.1111/risa.70008
