Association between dietary niacin intake and dyslipidemia prevalence in the National Health and Nutrition Examination Surveys (NHANES).

Background and objectives: The association of niacin intake with dyslipidemia remains uncertain. The aim of this study was to explore the association between dietary niacin intake and the prevalence of dyslipidemia among adults in the United States (US).

Methods and study design: Data were obtained from the National Health and Nutrition Examination Survey (NHANES) conducted between 2005 and 2014. The exposure variable was dietary niacin intake, measured through 24-hour dietary recall interviews and treated as both a continuous and categorical variable. Dyslipidemia, defined by diagnostic criteria, was the outcome. Logistic regression and restricted cubic spline models were applied to examine the association between niacin intake and the prevalence of dyslipidemia.

Results: Among the 19,275 individuals, the prevalence of dyslipidemia was 78.8%. Compared with individuals with lower niacin consumption Q1 (≤15.9 mg/day), the adjusted OR values for dietary niacin intake and dyslipidemia in Q3 (22.7-31.8 mg/day) and Q4 (≥31.8 mg/day) were 0.78 (95% CI: 0.64-0.94, p = 0.011) and 0.77 (95% CI: 0.61-0.98, p = 0.033), respectively. The association between niacin intake and the prevalence of dyslipidemia followed a L-shaped dose-response curve (non-linear, p = 0.009). Participants with a niacin intake of <22.3 mg/day exhibited an OR of 0.98 (95% CI: 0.96-0.99, p = 0.040) for dyslipidemia. In subgroup analyses, the inverse associations of niacin intake with the prevalence of dyslipidemia remained robust only in female.

Conclusions: In the 2005-2014 NHANES popu-lation, higher levels of niacin intake were associated with decreased odds of dyslipidemia overall. Further studies are needed to examine the potential protective effects of niacin on dyslipidemia risk.