Purpose: Although evidence strongly supports that antioxidant-rich diets reduce risk of chronic disease and mortality, findings from the previous studies on the effect of individual antioxidants on mortality have been inconsistent. The aim of this study was to assess the relationship between dietary total antioxidant capacity (TAC) and all-cause and disease-specific mortality in a representative sample of the US population.
Methods: A total of 23,595 US adults aged 30 years and older in NHANES 1988-1994 and 1999-2004 were selected for this study. Dietary TAC was calculated from 1-day 24-h diet recall data at baseline and all-cause, cancer and cardiovascular disease (CVD) mortality was assessed through December 31, 2011.
Results: During a mean follow-up of 13 years, deaths from all-cause, cancer and CVD were 7157, 1578, and 2155, respectively. Using cause-specific Cox proportional hazards models, inverse associations and linear trends were observed between dietary TAC and all-cause mortality [highest quartile (Q4) versus Q1 ref. HR 0.78; 95% CI 0.71-0.86], cancer mortality (Q4 versus Q1 ref. HR 0.75; 95% CI 0.60-0.93), and CVD mortality (Q4 versus Q1 ref. HR 0.83; 95% CI 0.69-0.99), respectively, after adjusting for age, sex, ethnicity, and total energy intake. The inverse association and linear trend still remained between dietary TAC and all-cause mortality (Q4 versus Q1 ref. HR 0.79; 95% CI 0.71-0.87) and CVD mortality (Q4 versus Q1 ref. HR 0.74; 95% CI 0.61-0.89) when further adjusted for relevant covariates.
Conclusions: These findings support that antioxidant-rich diets are beneficial to reducing risk of death from all-cause and CVD.
Keywords: Cancer; Cardiovascular disease; Mortality; NHANES; Total antioxidant capacity.