Brazil nuts are a popular type of nut known for their high selenium content, an essential mineral with antioxidant and anti-inflammatory properties. A recent clinical trial focused on women with overweight or obesity found that consuming 8 grams of Brazil nuts daily may reduce inflammation and improve intestinal permeability in just 8 weeks. While experts generally agree that consuming Brazil nuts is safe and beneficial for most people, it is advised to limit consumption to 1–2 nuts per day to prevent selenium toxicity.
Selenium is crucial for antioxidant defense, immune function, and thyroid hormone metabolism, and low levels of this mineral in the bloodstream are linked to various inflammatory conditions, including gut health problems. Previous research has shown connections between obesity, inflammation, and gut issues such as leaky gut, where the gut lining becomes more permeable, allowing harmful substances to enter the bloodstream and trigger inflammation. Eating Brazil nuts, with their high selenium content, may help improve these health markers and reduce inflammation.
The recent study conducted in Brazil involved 56 women with overweight or obesity who followed an 8-week calorie-reduced diet. Participants were split into control and Brazil nut groups, with the latter consuming 8 grams of Brazil nuts daily. Both groups were provided with controlled-ingredient salad dressings to balance fat and calorie intake. The study found that the group consuming Brazil nuts experienced an increase in selenium levels and reductions in inflammatory markers such as C-reactive protein levels. They also showed slightly improved intestinal permeability markers compared to the control group.
However, the study had limitations, including a small sample size and short duration. The findings may not be generalizable to other populations, and the participants were not randomized or blinded to the interventions. Diet adherence was mainly monitored through self-reports, which can introduce errors. Additional research with more controlled study designs is needed to clarify the effects of selenium, polyunsaturated fats, and fiber on inflammation and gut health. Experts suggest that Brazil nuts should be part of a healthy dietary pattern, along with other gut-health-promoting foods like those found in the Mediterranean or MIND diet.
Registered dietitians emphasize the importance of consuming 1-2 Brazil nuts per day, as they provide a significant amount of selenium. However, it is essential to monitor selenium intake from both supplements and foods to avoid toxicity, as excess selenium can lead to various health issues. Symptoms of selenium toxicity can include hair loss, skin rashes, and neurological problems. Incorporating Brazil nuts alongside other nutrient-dense foods in a balanced diet may help reduce inflammation and improve gut health, but they should not be considered a standalone solution. Organic and raw Brazil nuts are preferable, but the difference in nutrients between raw and roasted nuts is minimal.