The obesity pandemic exerts immense biomedical and socioeconomic burdens within developed and developing countries with global prevalence doubling since 1980. The pathological accumulation of adipose tissue characterizing obesity phenotypes continues to be the leading risk factor to many chronic and metabolic diseases while epidemiological research has established clear genetic and environmental etiologies. Of the multifactorial causes, nutrition, dyslipidemias, and adiopokines including leptin, are implicated in obesity pathogenesis. Recent research suggests vitamin D affects both serum leptin and obesity phenotypes. However, established associations between vitamin D intake and serum leptin levels remain largely ambiguous.

We analyze samples from 2003-2005, collected from a population of central Kansas Mennonites (n= 160: 76 males, 84 females) in order to assess the correlation between vitamin D intake and serum leptin levels. Three nonconsecutive day dietary diaries were previously analyzed for nutrient content through NutriBase Professional software and serum leptin levels analyzed at SFBR per their 2003 protocols. Both factors natural log transformed for normality. Linear regression was used to account for differential effects of body fat distribution on leptin levels, using anthropometric measures of both central and peripheral deposits. Applying univariate ANOVA on standardized leptin residuals, vitamin D intake was significantly associated with leptin levels in both combined (p=0.02) and sex-stratified samples (p=0.04 both sexes). Despite observed sexual dimorphism of leptin in this population, vitamin D intake influences serum leptin levels in both sexes. Research examining metabolic systems underlying this role is needed.