Daily tree nut intake may improve waist circumference, lipid biomarkers and insulin levels
A recent study published in Nutrients set out to determine whether consuming tree nuts as snacks, versus typical carbohydrate snacks, would reduce risk for metabolic syndrome in young adults. The study was the first of its kind to investigate cardiometabolic responses to tree nut snacks versus typical carbohydrate snacks among young adults at risk of metabolic syndrome.
The study was a prospective, randomized, parallel-group dietary intervention trial conducted in 84 adults aged 22–26, most of whom were overweight or obese (body mass index 24.5–34.9 kg/m2) and had at least one clinical risk factor for metabolic syndrome (abdominal obesity, elevated triglycerides, low HDL (“good”) cholesterol, high blood pressure, or elevated levels of blood glucose). Participants consumed either one ounce of tree nuts or one ounce of a carbohydrate-rich snack twice daily. Both snacks provided the same number of calories, protein, fiber and sodium and were part of a seven-day weight maintenance menu that repeated throughout the 16-week study period.
The findings showed that snacking on tree nuts instead of carbohydrate snacks was associated with a reduction in waist circumference and a trend toward reduced visceral fat in women. It was also associated with decreased blood insulin levels in men. Tree nut snacks were also associated with an 11% decrease in the ratio of triglycerides to HDL cholesterol. Finally, metabolic syndrome score —calculated for each participant by assigning one point for each metabolic risk criterion met— saw a 67% and 42% reduction, respectively, in women and men who ate tree nut snacks compared to those who ate carbohydrate snacks.
These results suggest that substituting typical high-carbohydrate snacks with tree nuts would likely reduce the risk of metabolic syndrome and its consequences in young adults by improving waist circumference, lipid biomarkers and insulin sensitivity —all without requiring caloric restriction.
This study was funded by the International Tree Nut Council Nutrition Research & Education Foundation (INC NREF).
Sumislawski, K., Widmer, A., Suro, R.R., Robles, M.E., Lillegard, K., Olson, D., Koethe, J.R., Silver, H.J. (2023). Consumption of tree nuts as snacks reduces metabolic syndrome risk in young adults: A randomized trial. Nutrients, 15, 5051.