Serum Carotenoid Levels and Risk of All-Cause and Cause-Specific Mortality in US Adults

Abstract

Abstract Objectives Carotenoids are bioactive compounds abundant in plant foods and they are thought to provide health benefits in decreasing the risk of chronic diseases. However, studies about serum carotenoid levels and long-term mortality were limited and the findings were controversial. This study examined the association of serum levels of total and individual carotenoids with all-cause mortality, cardiovascular disease (CVD) mortality, and cancer mortality. Methods This nationally representative cohort includes 8874 adults aged 18 years or older from the National Health and Nutrition Examination Survey 2003–2006. Serum levels of α-carotene, trans-β-carotene, cis-β-carotene, β-cryptoxanthin, combined Lutein/zeaxanthin, and lycopene were measured. Total carotenoids were the sum of these individual carotenoids. All participants were linked to mortality data through December 31, 2015. We used Cox proportional hazards regression models with survey weights to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results During on average 10.1 years (maximum 13.1 years) of observation, 1497 deaths occurred including 363 deaths from CVD and 306 deaths from cancer. After adjustment for age, sex, race/ethnicity, socioeconomic status, and dietary and lifestyle factors, the HR (95% CI) comparing the highest with the lowest quartile of serum total carotenoid levels was 0.71 (0.58–0.88) for all-cause mortality and 0.65 (0.49–0.87) for CVD mortality. There was no significant association between serum total carotenoid levels with cancer mortality (HR 0.80, 95% CI 0.55–1.17). For specific types of carotenoids, higher levels of α-Carotene, trans-β-carotene, cis-β-carotene, combined Lutein/zeaxanthin, and lycopene were associated with reduced risk of all-cause mortality, with the adjusted HRs ranging from 0.66 to 0.83. Higher serum levels of combined Lutein/zeaxanthin and lycopene were associated with a lower risk of CVD mortality, while trans-β-carotene, cis-β-carotene, and β-cryptoxanthin were associated with a lower risk of cancer mortality. Conclusions In this nationally representative study, higher levels of serum total carotenoids or several specific types of carotenoids were associated with lower risks of all-cause mortality and CVD mortality. Some carotenoids were associated with a lower risk of cancer mortality. Funding Sources N/A.