Which nuts are high in selenium? The definitive guide to boosting your intake

October 1, 2025 •

4 min read

Brazil nuts are famously the most concentrated dietary source of selenium, with a single nut often exceeding the recommended daily intake for adults. While they are in a league of their own, other nuts can also contribute to a healthy selenium intake, playing a vital role in thyroid function and antioxidant defense.

Quick Summary

Brazil nuts are the most potent source of selenium among all nuts, but their intake must be limited to prevent toxicity. Other nuts like cashews and pistachios provide smaller but meaningful amounts. Understand the benefits, risks, and how to safely incorporate these nuts into a balanced diet.

Key Points

Brazil Nuts are King: Just 1-2 Brazil nuts provide more than the daily selenium requirement, but overconsumption can lead to toxicity.
Practice Moderation: To avoid selenosis, limit your intake of Brazil nuts to just a few per week and enjoy a variety of other nuts.
Other Nuts Contribute Safely: Cashews and sunflower seeds offer moderate, safer levels of selenium compared to Brazil nuts.
Look Beyond Nuts: While excellent sources, don't rely solely on nuts for selenium. Include other foods like seafood and eggs in your diet.
Understand Health Benefits: Selenium supports critical bodily functions, including antioxidant defense, thyroid health, and immune support.
Diversify Your Diet: Eating a variety of nuts provides a wider range of nutrients beyond just selenium, including healthy fats, magnesium, and zinc.

Brazil Nuts: The unparalleled king of selenium

When considering which nuts are high in selenium, Brazil nuts stand alone at the top of the list. Just one to two Brazil nuts can provide the entire Recommended Dietary Allowance (RDA) for selenium for an adult, which is around 55 micrograms (mcg). The selenium content in Brazil nuts is exceptionally high and can vary depending on the soil conditions where the trees grow.

This high concentration makes them a uniquely potent source, but it also means moderation is crucial. The Tolerable Upper Intake Level (UL) for adults is 400 mcg per day, and eating too many Brazil nuts can lead to selenium toxicity, or selenosis. Symptoms of selenosis can include hair loss, brittle nails, and gastrointestinal issues. To safely reap the benefits, most health experts recommend limiting intake to just one or two Brazil nuts a few times per week.

Health benefits of adequate selenium intake

Selenium is a trace mineral vital for numerous bodily functions. Incorporating selenium-rich foods, including nuts, offers several health advantages:

Antioxidant power: Selenium plays a crucial role in antioxidant activity, helping to neutralize free radicals that can cause cellular damage and contribute to chronic disease.
Thyroid health: The thyroid gland has the highest concentration of selenium in the body. It is essential for the production of thyroid hormones and helps protect the gland from damage.
Immune system support: An adequate selenium level is critical for a healthy immune system, aiding in protecting the body from infections.
Cognitive function: Research suggests that selenium's antioxidant and anti-inflammatory properties may have a protective effect on the brain, potentially benefiting those with cognitive decline.

Other nuts that contain selenium

While no other nut can compete with the concentration found in Brazil nuts, other varieties offer smaller, safe doses that can still contribute to your overall intake. Since the selenium content in plants is highly dependent on the soil quality, the values for these nuts can vary. However, some reliably contain a moderate amount compared to fruits and vegetables.

Cashews: These popular nuts contain a respectable amount of selenium and are also excellent sources of zinc and magnesium.
Pistachios: Providing a smaller but notable amount of selenium, pistachios are also valued for their rich content of other nutrients, including potassium and vitamin B6.
Macadamia Nuts: While their selenium content is modest, macadamias are known for their high levels of healthy monounsaturated fats.
Walnuts: These are a good source of omega-3 fatty acids, and although their selenium level is lower than Brazil nuts, they offer a wider range of other minerals and vitamins.

How to incorporate nuts into your diet for selenium

Adding selenium-rich nuts to your meals is simple and can be done in many delicious ways. For Brazil nuts, remember that a little goes a long way. Chop them and sprinkle over oatmeal or yogurt, or add them to a trail mix with other nuts and seeds. For other nuts, you can be a bit more generous.

Here are some ideas for incorporating a variety of nuts into your diet:

Create a homemade trail mix with Brazil nuts, cashews, and sunflower seeds.
Chop cashews or pistachios and add them to salads for extra crunch and nutrients.
Use walnuts as a topping for pasta dishes or as a crust for chicken or fish.
Blend a couple of Brazil nuts into a smoothie to quickly boost your selenium intake.
Enjoy a small handful of mixed nuts as a daily snack.

Comparing nuts for selenium content (per 1 ounce/28g serving)


Nut Type	Selenium Content (approx. mcg)	Key Nutrients	Considerations
Brazil Nuts	~544	Healthy fats, magnesium, calcium	Very high concentration, eat in strict moderation to avoid toxicity.
Sunflower Seeds	~20	Vitamin E, healthy fats, magnesium	A good, safe source to add to many dishes.
Cashews	~20	Magnesium, zinc, copper	Versatile for cooking and snacking, lower selenium level.
Walnuts	~5	Omega-3s, antioxidants, healthy fats	Excellent for heart and brain health, low selenium level.
Pistachios	~3	Vitamin B6, potassium, fiber	Modest selenium, good for snacking and adding to salads.

*Note: The selenium content in nuts, particularly Brazil nuts, can vary widely based on the soil where they were grown.

Conclusion

When answering which nuts are high in selenium, Brazil nuts are the clear and undisputed winner. They are an incredibly potent source, but their power comes with the need for careful moderation to prevent toxicity. For a steady, safe, and balanced intake of this essential mineral, it is wise to incorporate a variety of other nuts, like cashews and sunflower seeds, which provide a smaller dose alongside a broad spectrum of other valuable nutrients. By being mindful of portion sizes and diversifying your choices, you can effectively use nuts as a key part of your nutrition diet for a healthy and thriving body. For more information, consult reliable nutrition sources like the National Institutes of Health.

Frequently Asked Questions

Brazil nuts are, by far, the nut with the most selenium. Just one to two Brazil nuts can contain enough selenium to meet the recommended daily intake for an adult.

Yes, it is possible to consume too much selenium, especially by overeating Brazil nuts. The Tolerable Upper Intake Level (UL) for adults is 400 mcg per day, and a single Brazil nut can push you close to that limit. Chronic overconsumption can lead to selenosis, a toxic state.

While other nuts contain far less selenium than Brazil nuts, varieties like cashews and sunflower seeds can contribute to your daily intake. Sunflower seeds offer a respectable amount, and cashews contain a moderate level.

To be safe, it's best to limit your intake of Brazil nuts to one or two nuts a few times per week. The selenium content can vary, so practicing moderation prevents you from exceeding the tolerable upper intake level.

Symptoms of selenium toxicity, or selenosis, include hair loss, brittle nails, skin rashes, and gastrointestinal issues like nausea and diarrhea. In severe cases, it can cause more serious complications.

Yes, the amount of selenium in nuts, especially Brazil nuts, is highly dependent on the soil quality where they were grown. This variation is why it is recommended to eat them in moderation.

For a safe and balanced intake, enjoy a single Brazil nut a few times a week. Supplement your intake with other selenium-containing foods like seafood and eggs, and incorporate a variety of other nuts in your diet.