Variability in Salivary Cortisol is Associated with Body Mass Index and Diet Quality

Abstract

Abstract Objectives Stress can negatively impact lifestyle practices and metabolic health, thereby increasing an individual's risk for chronic disease. We investigated whether variability in salivary cortisol levels is associated with body composition, blood pressure, and diet quality. Methods In this ongoing study, adult men and women (18–70y, n = 17) participated in a fasted baseline health assessment to measure body composition and resting blood pressure. Dietary intake was assessed over a 5-day period, where saliva samples were collected in the morning, afternoon, and evening to measure cortisol levels. Degree of cortisol variability over the 5-day period was calculated as: the highest recorded cortisol measurement - the lowest recorded cortisol measurement, which was used to classify subjects into groups of high (n = 9) and low (n = 8) cortisol variability. Results Subjects with greater variability in salivary cortisol had higher cortisol levels on average, in addition to greater concentrations and variability in cortisol levels in the morning. High variability in cortisol levels was additionally associated with a higher body mass index and metabolic age, but was not associated with fat or fat-free mass, waist circumference, or blood pressure. Subjects with lower variability in salivary cortisol levels reported having a greater dietary intake of linoleic acid and manganese, as well as a trend toward greater intake of vitamin D. Greater variability in salivary cortisol levels positively correlated with the % of dietary calories coming from fat, total fructose, serine, fried potatoes, dairy-based desserts, sweetened coffee, and beer. Conclusions Our preliminary findings demonstrate that high variability in salivary cortisol is associated with elevated morning stress hormone levels, body mass index, and a less favorable dietary pattern. Funding Sources This study was funded by the Fairfield University College of Arts and Sciences and a Vincent Rosivach Collaborative Research Grant.