The Claim
Selenium concentration in Brazil nuts varies across the Amazon region from 2.07 to 68.15 mg/kg, resulting in a single nut providing between 11% and 288% of the daily selenium requirement for an adult male (70 μg) depending on geographic origin.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
Brazil nuts from different parts of the Amazon contain different amounts of selenium, so one nut can supply anywhere from 11% to 288% of the daily selenium need for an adult man.
See the scientific wording
Selenium concentration in Brazil nuts varies widely across the Amazon region, ranging from 2.07 to 68.15 mg/kg, meaning a single nut can provide between 11% and 288% of the daily selenium requirement for an adult male (70 μg), depending on geographic origin.
Brazil nut trees absorb selenium from the soil through their roots, and the amount of selenium in the soil depends on the underlying rock and sediment. Trees growing in selenium-rich soil produce nuts with high selenium levels, while trees in selenium-poor soil produce nuts with low selenium levels.
What the research says
1 studyStudy: Natural variation of selenium in Brazil nuts and soils from the Amazon region.
Brazil nuts from different parts of the Amazon have wildly different amounts of selenium—some nuts give you barely enough for one day, while others give you more than two days’ worth, just because of where they grew.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.