Diet Quality and Circulating Sphingolipids: The Strong Heart Family Study

Abstract

Sphingolipids, including ceramides (Cer) and sphingomyelins (SM), are involved in the development of chronic disease through stress response, inflammation, insulin sensitivity, and more. Plasma sphingolipids may be influenced by dietary factors, but studies linking the two are limited. Among 2025 non-diabetic participants in the Strong Heart Family Study, we used food frequency questionnaire responses to calculate diet quality scores [Diabetes Dietary Index (DDI; constructed from foods related to type 2 diabetes risk), and the Alternative Healthy Eating Index- 2010 (AHEI)]. Associations of diet scores with 15 plasma sphingolipid species were assessed using linear mixed models. Higher DDI scores were associated with lower levels of Cer-18 (Geometric mean [GM] ratio: 0.93; 95%CI: 0.88-0.98) and higher levels of SM-20 (GM Ratio: 1.03; 95%CI: 1.000-1.065) when comparing the 90^th percentile to the 10^th percentile. Higher AHEI scores were associated with higher levels of SM-14 (GM Ratio: 1.07; 95%CI: 1.028- 1.121), SM-20 (GM Ratio: 1.03; 95%CI: 1.003-1.06), and SM-24 (GM Ratio: 1.04; 95%CI: 1.013-1.074). BMI modified associations of DDI with SM-14, SM-16, SM-20, and SM-24; and age modified the association of DDI with SM-24. Higher diet quality is associated with lower Cer-18 and higher SM-14, SM-20, SM-24. BMI appears to modify associations of diet quality with plasma sphingomyelins. These studies need to be replicated in prospective studies and other populations.