Bertholletia excelsa
Brazil nuts are large seeds from the Amazonian tree Bertholletia excelsa and are one of the richest known dietary sources of selenium.
They are most strongly supported by evidence for improving selenium status and enhancing antioxidant enzyme activity. In a longevity context, Brazil nuts are particularly relevant due to their role in supporting endogenous antioxidant systems and reducing oxidative stress.
Brazil nuts are uniquely high in selenium,a trace mineral essential for human health.
Selenium is required for the function of selenoproteins such as glutathioneperoxidase (GPx), which plays a central role in antioxidant defence.
Brazil nuts can provide more selenium per gram than almost any other food,making them one of the most efficient dietary sources of this nutrient. Brazil nuts contain key nutrients including:
- Selenium
- Healthy fats
- Magnesium
- Vitamin E
- Polyphenols
Brazil nuts increase selenium status and activity of antioxidant enzymes such as GPx.
Improved antioxidant enzyme activity helps reduce oxidative stress, a key driver of ageing.
Some studies show improvements in oxidized LDL and HDL cholesterol.
Provides an efficient whole-food source of selenium.
Randomised controlled trial · Healthy adults · 12 weeks
Brazil nuts were as effective as selenium supplementation in increasing plasma selenium and glutathione peroxidase activity.
View study on PubMed →Randomised controlled trial · Adults with obesity · 8 weeks
Increased selenium status and HDL cholesterol, with improvements in cardiovascular risk markers.
View study on PubMed →Systematic review and meta-analysis of RCTs · Hypertensive and dyslipidaemic adults
Brazil nut consumption consistently increases selenium levels and GPx activity, with more variable effects on lipid markers.
View study on PubMed →Brazil nuts are one of the most effective whole-food sources of selenium, with strong human evidence supporting their role in improving antioxidant enzyme activity and reducing oxidative stress. Their primary benefit lies in supporting endogenous antioxidant defence, with additional but less consistent evidence for cardiovascular effects.
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