Alpha-Linolenic Acid and Mortality Among Adults With Type 2 Diabetes: Findings From Two National Cohorts

Dietary alpha-linolenic acid (ALA) regulates lipid metabolism and insulin sensitivity, but few studies have investigated the association between ALA and the risk of mortality among adults with type 2 diabetes (T2D). This study examines whether increasing dietary ALA intake contributes to the long-term survival of adults with T2D.

This cohort study included 9603 participants with T2D, including 7953 adults from the National Health and Nutrition Examination Survey (NHANES; 1999-2018) and 1650 adults from the China Health and Nutrition Survey (CHNS; 1997-2011). Dietary information was collected through 24-h dietary recalls. Cox proportional hazards regression was employed to estimate hazard ratios (HRs) and 95% CIs for mortality from all-cause and cardiovascular disease (CVD).

During 75 535 person-years of follow-up, a total of 2468 deaths were documented. After multivariate adjustment, the pooled HRs (95% CIs) of all-cause mortality were 1.00, 0.87 (0.76-0.99), and 0.79 (0.67-0.94) across tertiles of ALA (p_trend = 0.01). There was a linear inverse relationship between ALA intake and all-cause mortality, demonstrating a 9% (HR: 0.91;95% CI: 0.85_0.97) lower risk of all-cause mortality with each 1 g/day increase of dietary ALA intake in the pooled analysis (p_nonlinear > 0.05). In addition, ALA intake was inversely associated with CVD mortality, and HR comparing the highest with the lowest tertile was 0.68 (0.50-0.91; p_trend = 0.01). Consistent results were observed in both the stratified and sensitivity analyses.

Higher dietary ALA intake was associated with a lower risk of all-cause and CVD mortality among adults with T2D.