(P29-019-23) Dietary Total Antioxidant Capacity, a Diet Quality Index Predicting Mortality Risk in US Adults: Evidence From the NIH-AARP Diet and Health Study

Objectives: Dietary total antioxidant capacity (TAC), which is a concept for assessing total antioxidant power of antioxidant nutrients and flavonoids in the diet, has received attention due to its potential as a novel predictor of health outcomes and an indicator of diet quality in assessing antioxidant-rich dietary patterns. This study aimed to investigate association between dietary TAC including from foods and dietary supplements and mortality risk in US adults based on the NIH-AARP Diet and Health Study data.

Methods: Study participants were enrolled in 1995–1996 and a total of 468,733 adults aged 50–71 years were included in this study. Dietary intake was assessed using a food frequency questionnaire. Dietary TAC from foods and beverages was calculated from the vitamin C equivalent antioxidant capacity of antioxidants including vitamin C, vitamin E, carotenoids, and flavonoids, and TAC from dietary supplements was calculated similarly from supplemental vitamin C, vitamin E, and beta-carotene intakes.

Results: During a median follow-up of 23.1 years, 241,472 deaths were identified. Dietary TAC was inversely associated with all-cause (hazard ratio (HR) for quintile 5 vs. quintile 1: 0.97, 95% confidence interval (CI): 0.96–0.99, p for trend < 0.0001) and cancer mortality (HR for quintile 5 vs. quintile 1: 0.93, 95% CI: 0.90–0.95, p for trend < 0.0001). The participants in the highest quintile of dietary TAC from foods had a decreased CVD mortality risk, as well as all-cause and cancer mortality. However, dietary TAC from dietary supplements was inversely associated with cancer mortality risk only.

Conclusions: These findings indicate that dietary TAC can be a valuable tool to predict mortality risk and dietary TAC from foods might confer more health benefits rather than dietary TAC from dietary supplements.

Funding Sources: None