What is the Side Effect of Brown Rice? A Look at Potential Health Concerns

October 31, 2025 •

4 min read

According to a study published in the journal Risk Analysis, brown rice can contain significantly higher levels of inorganic arsenic than its white counterpart, posing a potential risk, especially for young children. Understanding what is the side effect of brown rice is crucial for making informed dietary choices, despite its recognized nutritional benefits.

Quick Summary

Brown rice has several potential drawbacks, including a higher content of inorganic arsenic, digestive discomfort due to high fiber, and reduced mineral absorption from phytic acid.

Key Points

Arsenic Risk: Brown rice has higher levels of inorganic arsenic, a known carcinogen, primarily concentrated in its outer bran layer.
Mineral Absorption: Phytic acid in brown rice can inhibit the body's absorption of key minerals like iron, zinc, and calcium, though this is less of a concern with a varied diet.
Digestive Issues: The high fiber content and FODMAPs can cause bloating, gas, or stomach cramps, especially for individuals with sensitive digestive systems or IBS.
At-Risk Groups: Pregnant women, young children, and individuals with mineral deficiencies or digestive sensitivities should be especially mindful of their brown rice consumption.
Mitigation Strategies: Proper preparation, such as rinsing thoroughly, soaking, and cooking in excess water, can significantly reduce arsenic and phytic acid content.
Dietary Variety: Eating a variety of grains rather than relying solely on brown rice helps minimize exposure to contaminants and ensures a broader spectrum of nutrients.

For years, brown rice has been hailed as a nutritional powerhouse, often recommended over white rice due to its higher fiber, vitamin, and mineral content. However, its whole-grain nature, which keeps the nutrient-rich bran and germ layers intact, is also the source of some potential health drawbacks. Concerns primarily revolve around naturally occurring contaminants and compounds that can affect digestion and nutrient absorption. While these side effects do not negate brown rice’s many health benefits for most people, awareness allows for mitigation and ensures the safest consumption, particularly for vulnerable populations.

The Higher Arsenic Content in Brown Rice

One of the most significant and well-documented side effects of brown rice is its higher level of arsenic. Arsenic is a toxic heavy metal that exists naturally in the soil and water. The rice plant readily absorbs this element from its environment, and since arsenic tends to accumulate in the outer bran layer, brown rice contains more of it than white rice, where the bran has been stripped away. Inorganic arsenic is the more toxic form and is classified as a human carcinogen.

Chronic, long-term exposure to high levels of arsenic has been linked to a range of serious health problems. These include an increased risk of several types of cancer (skin, bladder, and lung), cardiovascular disease, and Type 2 diabetes. For young children and pregnant women, the risks are particularly elevated, as arsenic exposure during early development has been associated with lower IQ, learning difficulties, and developmental problems.

Mitigating Arsenic Risk in Brown Rice

Fortunately, there are several effective strategies for reducing the arsenic content in your brown rice. These methods involve careful preparation to wash away contaminants.

Rinse thoroughly: Rinsing raw rice before cooking can wash off some of the surface-level arsenic.
Use excess water: A cooking method that involves using a 1-to-6 cup ratio of rice to water, then draining the excess water after cooking, can significantly reduce arsenic levels.
Choose lower-arsenic varieties: Some rice varieties, like basmati from California, India, or Pakistan, tend to have lower arsenic levels.
Vary your grains: Incorporating other whole grains like quinoa, barley, and oats into your diet instead of relying solely on rice can help minimize overall arsenic exposure.

The Impact of Phytic Acid on Mineral Absorption

Brown rice, like other whole grains, contains a compound called phytic acid, or phytate. Phytic acid is an anti-nutrient, meaning it binds to certain minerals and reduces their absorption in the body. Specifically, it can inhibit the uptake of essential minerals like iron, zinc, calcium, and magnesium. For individuals consuming a well-balanced diet, this effect is often minor and does not cause significant mineral deficiencies. However, for those with nutrient-poor diets, those with pre-existing mineral deficiencies, or vegetarians/vegans who rely heavily on grains for nutrition, it could be a concern over time.

How to Reduce Phytic Acid Levels

Cooking and preparation techniques can effectively reduce phytic acid content and improve mineral bioavailability:

Soaking: Soaking brown rice before cooking, particularly in warm water, can reduce phytic acid levels.
Sprouting: Germinating or sprouting brown rice activates enzymes (phytases) that break down phytic acid, significantly lowering its concentration.
Fermenting: Certain fermentation processes can also help to break down phytic acid.

Digestive Discomfort from High Fiber Content

Brown rice is a rich source of dietary fiber, which is largely found in its intact bran layer. While beneficial for most, this high fiber content can cause digestive discomfort for some individuals, leading to symptoms like bloating, gas, and stomach cramps. The coarse bran and germ can also irritate a sensitive digestive tract. Furthermore, brown rice contains fermentable carbohydrates known as FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols), which can exacerbate symptoms for those with irritable bowel syndrome (IBS) or other digestive sensitivities.

Brown Rice vs. White Rice: A Nutritional and Risk Comparison


Feature	Brown Rice	White Rice
Processing	Minimally processed; retains bran, germ, and endosperm.	Milled to remove bran and germ, leaving only endosperm.
Fiber	Significantly higher fiber content.	Low in fiber.
Nutrients	Richer in vitamins (B1, B3, B6), minerals (magnesium, potassium, manganese), and antioxidants.	Lower in most nutrients; often fortified with some vitamins and iron.
Arsenic Level	Higher inorganic arsenic content due to accumulation in the bran.	Lower arsenic content as the bran is removed during processing.
Phytic Acid	Higher levels of phytic acid, potentially affecting mineral absorption.	Lower levels due to the removal of the bran.
Digestibility	The higher fiber content can be harder to digest for some individuals.	Easier to digest due to lower fiber.
Glycemic Index (GI)	Lower GI (65-68), leading to slower blood sugar increases.	Higher GI (around 73), causing faster blood sugar spikes.

Conclusion: Balancing the Benefits and Risks

While brown rice offers substantial health benefits, including a lower glycemic index, higher fiber, and greater mineral content, it is not without its potential downsides. The increased risk of arsenic exposure and the presence of phytic acid are legitimate concerns, particularly for vulnerable groups such as children, pregnant women, and those with specific health conditions. For most healthy adults, the risks associated with moderate brown rice consumption are minimal and can be managed effectively through proper preparation techniques like rinsing and using excess water. The key to a healthy diet is variety, so rotating your grain intake with other options like quinoa, barley, and whole wheat can be a prudent approach to minimizing any single-source risks. Consult with a healthcare professional or dietitian if you have underlying health concerns or specific dietary needs. Brown rice remains a nutritious choice, but an informed approach to its consumption is the smartest path forward.

Healthline provides an in-depth guide to understanding phytic acid and its effects on mineral absorption.

Frequently Asked Questions

While generally safe for most healthy adults in moderation, brown rice poses potential risks due to higher arsenic and phytic acid levels. Young children, pregnant women, and those with digestive issues or mineral deficiencies should be cautious and limit their intake.

To reduce arsenic, rinse the rice thoroughly before cooking and use a cooking method with a high water-to-rice ratio (6:1 is recommended), then drain the excess water. Sourcing rice from regions known for lower arsenic content also helps.

Yes, for some people, especially those with sensitive digestion or IBS, the high fiber content and FODMAPs in brown rice can lead to digestive issues like bloating, gas, and cramps.

Brown rice contains phytic acid (phytate), an anti-nutrient that binds to minerals like iron, zinc, and calcium, which can reduce their absorption during a meal. Soaking and sprouting the rice can help break down this compound.

Not necessarily, it depends on individual needs. Brown rice is more nutritious overall but has higher arsenic and phytic acid levels. White rice is lower in nutrients but easier to digest and lower in contaminants. A balanced approach using a variety of grains is often best.

Pregnant women and young children are more vulnerable to arsenic and should limit their consumption of brown rice. The FDA and other health organizations recommend varying grain intake to minimize risk in these populations.

Brown rice has a shorter shelf life than white rice, typically around six months, because the natural oils in its bran and germ can go rancid. White rice, having these layers removed, is more shelf-stable.