Associations of dietary polyunsaturated fatty acids with dyslipidemia among the U.S. adults: the findings from NHANES 2009-2016.

Abstract

Dyslipidemia, a significant risk factor of cardiovascular disease, is threatening human health worldwide with a high economic burden. Polyunsaturated fatty acids (PUFAs) are crucial long-chain fatty acids for triglyceride synthesis and removal, potentially decreasing dyslipidemia risk. We examined dyslipidemia prevalence among 15,244 adults aged ≥20 years from NHANES 2009-2016. The dyslipidemia was defined as total cholesterol ≥240 mg/dL, or high-density lipoprotein cholesterol <40 mg/dL/50 mg/dL for males/females respectively, or low-density lipoprotein cholesterol ≥160 mg/dL, or triglyceride ≥200 mg/dL, or taking lipid-modifying medications. We measured the daily PUFA intake using a 24-h dietary recall. Demographics, social-economics, and lifestyle factors were collected using questionnaires/interviews. Additionally, we measured selenium and mercury levels in the whole blood. Logistic regression models were used to examine the association between PUFAs and dyslipidemia. The unweighted and weighted dyslipidemia prevalences were 72.4% and 71.0%, respectively. When grouped into tertiles, PUFA intake above 19.524 g/day was associated with an independent 19% decrease in dyslipidemia risk [O.R.=0.81(95%C.I.: 0.71-0.94)] compared with the lowest tertile (PUFA intake ≤12.349 g/day). A threshold inverse association was further determined by the restricted cubic spline analysis. When PUFA intake was increased to its turning point, i.e., 19 g/day, the lower nadir risk for dyslipidemia was obtained [O.R.=0.72(95% C.I.: 0.56-0.89)]. When the exposure was the sum of α-linolenic acid and octadecatetraenoic acid, the inverse linear association remained. Dietary PUFA intake is a beneficial factor for dyslipidemia among American adults, independent of many potential confounders, including mercury and selenium. Future prospective studies are warranted.