Brazil nuts are known as the richest natural food source of selenium, but the exact selenium content can vary widely depending on factors such as soil selenium levels, geographic location, and environmental conditions.
- On average, selenium content in Brazil nuts is about 290.5 micrograms per gram (μg/g), with some nuts containing up to 512 μg/g
. Other studies report ranges from about 8 to 83 μg/g or even wider depending on the region
- According to the USDA, a single Brazil nut contains approximately 96 micrograms (μg) of selenium
. Since an average Brazil nut weighs around 5 grams, this roughly aligns with the high selenium concentration per gram.
- Selenium content varies greatly: within Brazil itself, nuts have been found to range from 2.07 mg/kg (2.07 μg/g) in some areas to as high as 68.15 mg/kg (68.15 μg/g) in others
. This variability means selenium intake from Brazil nuts can differ significantly depending on the source.
- Typically, eating 1 to 2 Brazil nuts per day provides enough selenium to meet or exceed the recommended daily intake (RDI), which is about 55-70 μg for adults
. For example, 2 nuts can provide roughly 100 μg of selenium, effectively improving selenium status in humans
- Because selenium levels are so high, it is advised not to consume excessive amounts of Brazil nuts to avoid selenium toxicity. The upper safe limit is about 400 μg/day, which corresponds to roughly 4 to 7 nuts depending on their selenium content
In summary, a single Brazil nut typically contains around 96 micrograms of selenium, but this can vary widely. Consuming 1-2 nuts daily is sufficient to meet selenium needs, while eating many more can risk excessive intake due to their high selenium concentration. References are based on scientific studies and nutritional data from USDA and health organizations
