Evidence from epidemiologic studies has shown that total antioxidant capacity (TAC) in the diet might be inversely associated with stroke, heart failure, and inflammatory biomarkers. However, studies on the association of TAC from both diet and supplements with cardiovascular disease (CVD) risk factors in the U.S. population are lacking. This cross-sectional population-based study aimed to investigate the association of TAC with both diet and supplements with CVD risk factors among 4039 U.S. adults in National Health and Nutrition Examination Survey (NHANES) 2007-2012. TAC from both food sources and dietary supplements was estimated from two 24-h dietary recalls using the NHANES supplement ingredient database, United States Department of Agriculture (USDA) proanthocyanidin, flavonoid, and isoflavone databases. Top contributors to TAC were tea, antioxidant supplements, vegetable mixture, orange juice, berries, and wine. Antioxidant supplement users had 1.6 times higher TAC than non-users. Greater TAC was associated with reduced triglycerides (TG) (-1.39% change; 95% CI = -2.56 to -0.21), TG to high-density lipoprotein cholesterol (HDL-C) ratio (-2.03% change; 95% CI = -3.45 to -0.60), HDL-C (0.65% change; 95% CI = 0.07 to 1.23), insulin (-1.37% change; 95% CI = -2.64 to -0.09), homeostasis model assessment of insulin resistance (HOMA-IR) (-1.57% change; 95% CI = -3.02 to -0.09) and C-reactive protein (CRP) (-0.83% change; 95% CI = -1.29 to -0.38) after adjusting for potential confounders. There was no significant association between TAC and waist circumference, BMI, blood pressure, low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), and fasting glucose. The findings of this study support the hypothesis that an antioxidant-rich diet and intake of supplements are beneficial to reduce CVD risk.
Keywords: NHANES; blood lipids; cardiovascular disease; supplements; total antioxidant capacity.