Selenium is a trace element, or nutrient, that the body needs to stay healthy. The best sources of selenium include some nuts, fish, and poultry.

Keep reading to learn more about selenium and why we need it, as well as 15 foods that contain this important nutrient.

Selenium is a trace element, or nutrient, that humans need to stay healthy. It plays a role in many bodily processes, including:

  • reproduction
  • the function of the thyroid gland
  • production of DNA
  • protecting the body from free radicals, which are unstable cells that move around the body and can increase the risk of diseases, including cancer
  • protecting the body from infection

The amount of selenium people need depends on their age. Other factors include whether they are pregnant, or if they are breastfeeding. According to the National Institutes of Health (NIH), the recommended daily amounts are:

  • birth to 6 months: 15 micrograms (mcg)
  • infants 7–12 months: 20 mcg
  • children 1–3 years: 20 mcg
  • children 4–8 years: 30 mcg
  • children 9–13 years: 40 mcg
  • teenagers 14–18 years: 55 mcg
  • adults: 55 mcg
  • a person who is pregnant: 60 mcg
  • a person who is breastfeeding: 70 mcg

Selenium deficiency is rare in the United States. However, it can happen, and can lead to:

  • Keshan disease, which is a type of heart disease
  • infertility in men
  • Kashin-Beck disease, which is a type of arthritis that affects the joints

Scientists are currently investigating links between selenium deficiencies and:

  • cancer
  • cardiovascular disease
  • cognitive decline, which includes problems with memory, problem-solving, and concentration
  • cardiovascular disease
  • thyroid disease

It is worth noting that too much selenium can be harmful. Over time, it can lead to:

  • bad breath
  • nausea
  • diarrhea
  • rashes
  • irritability
  • a metallic taste in the mouth
  • discoloration of the teeth
  • brittle hair and nails
  • hair loss

The upper limit of selenium also depends on a person’s age. The NIH offers the following advice:

  • birth to 6 months: no more than 45 mcg per day
  • infants 7–12 months: no more than 60 mcg per day
  • children 1–3 years: no more than 90 mcg per day
  • children 4–8 years: no more than 150 mcg per day
  • children 9–13 years: no more than 280 mcg per day
  • teenagers 14 and older, and adults: no more than 400 mcg per day

Many foods contain selenium, including:

1. Brazil nuts

Brazil nuts are very high in selenium, with 1 ounce (oz), or 6–8 nuts, containing 544 mcg. That’s 989% of an adult’s recommended daily value (DV).

2. Tuna

Around 3 oz of cooked, yellowfin tuna contains 92 mcg of selenium, or 167% of the adult DV.

3. Halibut

The same size portion of halibut has 47 mcg, or 85% of the adult DV.

4. Sardines

Once drained, a 3 oz can of sardines in oil, with bones, will account for 82% of the adult DV. That’s because it contains 45 mcg of selenium.

5. Roasted ham

A 3 oz portion of roasted ham contains 42 mcg of selenium. That equates to 76% of the adult DV.

6. Shrimp

Around 3 oz of canned shrimp has 40 mcg of selenium, or 73% of the adult DV.

7. Enriched macaroni

Some brands of macaroni are enriched with selenium. Once cooked, one cup of this type of pasta will contain 37 mcg, or 67% of the adult DV.

8. Turkey

A 3 oz portion of boneless, roasted turkey contains 56% of the adult DV, which is 31 mcg.

9. Beef liver

Pan fried, 3 oz of beef liver can provide 28 mcg, or 51% of an adult’s DV.

10. Chicken

The light meat in chicken contains the selenium. People should aim for around 3 oz of roasted chicken to consume 22 mcg, or 40% of the adult DV.

11. Cottage cheese

One cup of 1% milk fat cottage cheese contains 20 mcg, or 36% of the adult DV.

12. Brown rice

Around one cup of cooked, brown, long-grain rice contains 35% of the adult DV, or 19 mcg.

13. Eggs

Eggs are also a good source of selenium. One large, hard-boiled egg will provide 15 mcg of the nutrient. That equates to 27% of the adult DV.

14. Bread

Bread can boost selenium levels, particularly if a person opts for brown varieties. On average, a slice of whole-wheat bread contains 24% of the adult DV, or 13 mcg.

15. Baked beans

Baked beans are a good source of selenium as well as protein. One cup will provide an adult with 24% of their DV, or 13 mcg.

Selenium is an essential nutrient. It plays an important role in many bodily processes, including reproduction, thyroid gland function, and DNA production.

The amount of selenium people need to consume every day changes as they get older. Babies need the least, and adults need the most. The nutrient is present in many foods, so deficiency is rare in the U.S.

Foods that contain selenium include Brazil nuts, some fish, poultry, brown rice, and wholemeal bread.