Brazil nut consumption promotes satiety without increasing blood glucose and insulin responses in healthy adults

Abstract

Brazil nuts are rich in important nutrients including unsaturated fatty acids and fiber and are the highest known food source of selenium. Selenium has exhibited a multitude of health benefits including increased antioxidant capacity, improvement of lipid profiles, insulin and glucose responses, and elevation of mood. The purpose of the present study was to determine the effects of Brazil nut consumption on postprandial satiety, glucose, insulin, antioxidant activity, and anxiety in healthy subjects. In a crossover design with two trials, 22 healthy adults (age 25 ± 4.94 years, BMI 22.3 ± 3.29 kg/m2) consumed pretzels (36 g) and isocaloric, sodium-matched Brazil nuts (20 g), separated by a 48-h washout period. A visual analogue scale measured satiety at baseline, 20 and 40 min after snack consumption. Anxiety (via modified STAI), blood glucose, insulin, and antioxidant levels were measured at baseline and 40 min. Both the Brazil nuts and pretzels increased satiety with greater satiety in Brazil nuts compared to pretzels (P = 0.049). Each snack also decreased anxiety (P = 0.020) from baseline to 40 min post-consumption with no significant differences between the two trials. Pretzel consumption caused a significant increase in blood glucose and insulin (P < 0.001) at 40 min post-consumption compared to baseline, while Brazil nut consumption did not significantly increase either level. Brazil nut consumption improved postprandial satiety and stabilized glucose and insulin responses compared to baseline, which warrants further studies on reducing overall food intake and preventing cardiovascular disease, diabetes, and weight gain.