Key Takeaways
  • Arsenic is naturally present in trace amounts in the environment and is also mixed into our food. Inorganic arsenic is considered particularly harmful.
  • Because Japanese people consume a lot of seafood, rice, and seaweed (especially hijiki), our arsenic intake tends to be higher compared to Western countries.
  • Since arsenic tends to accumulate in the bran layer, brown rice generally has higher levels of total and inorganic arsenic than polished white rice.
  • You can lower your risk by using cooking methods that reduce arsenic (such as washing thoroughly, soaking, cooking in plenty of water, and discarding the excess water) and by diversifying your diet.

Introduction: The "Arsenic" Hidden in Our Daily Food — Should We Be Worried?

Trace amounts of arsenic are found in the soil and water around us, and we consume it daily through crops and seafood. In the 1950s, cases of arsenic poisoning from infant formula occurred in Japan, which triggered subsequent investigations and regulations. While arsenic has long been a focus from a food safety perspective, it is difficult to eliminate it completely, and how we manage our exposure is a modern challenge. To be honest, when our team first saw the data, we were surprised by how much we were consuming, but by understanding it and taking action, we can lower the risks.

Types of Arsenic and Health Effects — The Difference Between Organic and Inorganic Arsenic

Inorganic and Organic Arsenic

Arsenic is broadly divided into inorganic and organic forms. Inorganic arsenic poses high health risks, including carcinogenicity, and the WHO (World Health Organization) closely monitors it. On the other hand, organic arsenic, which is abundant in seafood, is generally considered to have low toxicity, but this does not mean it is "safe to ignore." The effects vary depending on the intake amount and type, so caution is necessary.

Long-Term Effects

Long-term consumption of inorganic arsenic is associated with skin lesions, cancers of the lungs, skin, and bladder, as well as impacts on neurodevelopment. Infants, pregnant women, and growing children are particularly susceptible, making careful consideration essential when preparing baby food.

Actual Intake in Japan and Foods to Watch Out For

According to surveys by the Ministry of Agriculture, Forestry and Fisheries and Health and Labour Sciences Research, while total arsenic intake varies by country and region, for Japanese people, seafood, seaweed, and rice are the main sources. One estimate suggests that the average total arsenic intake per person in Japan is about 205 μg (121 μg from seafood, 62.2 μg from vegetables and seaweed, and 12.6 μg from rice). The fact that intake tends to be higher in Japan and other Asian countries compared to the West is largely due to differences in food culture.

Foods Requiring Special Attention

- Hijiki: Among seaweeds, hijiki is known for its high arsenic content, and restricting its intake is sometimes recommended for infants and pregnant women. From what we have researched, the golden rule is "do not consume too much hijiki." - Seafood: While species with high total arsenic levels (such as octopus, flounder, and shrimp) have been reported, the arsenic in most fish is primarily organic. It is important to understand the characteristics of each fish species. We should also consider other heavy metals like mercury. - Brown Rice: Because arsenic remains largely in the bran layer, brown rice tends to have higher total and inorganic arsenic levels than polished white rice. We need to weigh both the nutritional benefits of brown rice and the risks of arsenic when making our choices.

Practical Daily Countermeasures — Cooking Methods and Dietary Adjustments

Reducing Arsenic Through Cooking

To some extent, arsenic can be reduced through home cooking methods. Specifically, washing rice thoroughly, soaking it, cooking it in plenty of water, and discarding the excess water after cooking is considered effective. When we tried this, we found that properly washing and soaking the rice provided peace of mind without compromising its flavor. The effectiveness may vary depending on the type of pressure cooker or rice cooker, so please adapt the method to the cooking appliances you normally use.

Ingredient Selection and Balance

- Avoid giving infants too much hijiki or other foods where arsenic is a concern. For baby food, we recommend diversifying the diet around white rice, sweet potatoes, and legumes. - While brown rice is highly nutritious, infants and pregnant women in particular should avoid relying solely on it. Try adjusting the frequency or alternating it with polished white rice. - It is important to rotate the types of fish you eat and avoid regularly consuming species that are high in both total arsenic and mercury.

Utilizing Systems and Information

Check the latest guidelines and survey results published by the Ministry of Agriculture, Forestry and Fisheries, the Ministry of Health, Labour and Welfare, and the Food Safety Commission. Since regulations and recommendations can change, relying on credible public information will give you peace of mind.

Conclusion

Arsenic is a naturally occurring substance that cannot be completely avoided, but by understanding its types, amounts, and our food culture, we can adequately manage the risks. Especially in Japan, where intake through seafood, seaweed, and rice is higher, practical countermeasures include paying attention to hijiki consumption, how we handle brown rice, and our choice of fish species. We feel that by changing our awareness in our daily meals, we can reduce our exposure. Start by washing, soaking, adjusting your cooking methods, and diversifying your ingredients.

Disclaimer: The information in this article is for general informational purposes only and does not constitute medical advice. Please consult a qualified healthcare professional before making any health-related decisions.