Energy and Macronutrient Metabolism
Emerging research indicates that nuts are a source of compounds that promote cardioprotective benefits. However, most studies have assessed the effect of single nuts rather than a mixture containing a variety of nuts. Therefore, the objective of this study is to examine the effect of mixed nuts on cardiovascular disease risk factors including inflammation, glucose, insulin, antioxidant capacity, and liver function.
In an 8-week randomized controlled trial, 48 participants (19 female and 29 male, 18-54 years) were equally divided into groups that consumed isocaloric (250 kcal) amounts of pretzels (69g) or mixed nuts (42.5g) for 8 weeks. Serum lipids, inflammatory biomarkers, oxidative stress, antioxidant capacity, antioxidant enzymes, and markers of liver function were measured at baseline and 4 weeks and 8 weeks after intervention.
Results : Significant decreases were detected for body weight (P=0.013) and BMI (P=0.022), but only within the nut group. Nut consumption reduced glucose (P=0.040) and insulin (P=0.032) concentrations after 4 and 8 weeks, respectively; whereas, pretzel intake increased triglycerides (P=0.048) between week 4 to week 8. While total cholesterol did not change, HDL-C (P=0.044) dropped and LDL-C (P=0.038) increased from baseline to week 4 of pretzel consumption with no significant changes in the nut group. Among liver function biomarkers, alkaline phosphatase exhibited a reducing trend from baseline to week 8 of nut ingestion and lactate dehydrogenase decreased significantly from baseline and week 4 to week 8 (P< 0.01), while it increased within the pretzel group at week 8 compared to baseline (P=0.018).
Conclusions : Our results suggest that the incorporation of mixed-nuts into the diet improves body weight, some liver and cardiac functions, and maintains total cholesterol, triglyceride, HDL-C, and LDL-C levels in comparison to a refined snack food. Future research should determine whether nuts impact cardiovascular disease outcomes.
Funding Sources : American Heart Association (16GRNT31360007)