Dietary choline is positively related to overall and cause-specific mortality: results from individuals of the National Health and Nutrition Examination Survey and pooling prospective data.

Little is known about the association between dietary choline intake and mortality. We evaluated the link between choline consumption and overall as well as cause-specific mortality by using both individual data and pooling prospective studies by meta-analysis and systematic review. Furthermore, adjusted means of cardiometabolic risk factors across choline intake quartiles were calculated. Data from the National Health and Nutrition Examination Survey (1999-2010) were collected. Adjusted Cox regression was performed to determine the risk ratio (RR) and 95 % CI, as well as random-effects models and generic inverse variance methods to synthesise quantitative and pooling data, followed by a leave-one-out method for sensitivity analysis. After adjustments, we found that individuals consuming more choline had worse lipid profile and glucose homeostasis, but lower C-reactive protein levels (P < 0·001 for all comparisons) with no significant differences in anthropometric parameters and blood pressure. Multivariable Cox regression models revealed that individuals in the highest quartile (Q4) of choline consumption had a greater risk of total (23 %), CVD (33 %) and stroke (30 %) mortality compared with the first quartile (Q1) (P < 0·001 for all comparison). These results were confirmed in a meta-analysis, showing that choline intake was positively and significantly associated with overall (RR 1·12, 95 % CI 1·08, 1·17, I2 = 2·9) and CVD (RR 1·28, 95 % CI 1·17, 1·39, I2 = 9·6) mortality risk. In contrast, the positive association between choline consumption and stroke mortality became non-significant (RR 1·18, 95 % CI 0·97, 1·43, P = 0·092, I2 = 1·1). Our findings shed light on the potential adverse effects of choline intake on selected cardiometabolic risk factors and mortality risk.