The rate of cortisol decline after consuming a high-fat test meal for breakfast partially explained sex-dependent variation in post ingestive cardiovascular status

Authors: Laugero, Kevin; Snodgrass, Ryan; Keim, Nancy

Submitted to: Current Developments in Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/2/2026
Publication Date: 2/6/2026
Citation: Laugero, K.D., Snodgrass, R.G., Keim, N.L. 2026. The rate of cortisol decline after consuming a high-fat test meal for breakfast partially explained sex-dependent variation in post ingestive cardiovascular status. Current Developments in Nutrition. 10(3). https://doi.org/10.1016/j.cdnut.2026.107655.
DOI: https://doi.org/10.1016/j.cdnut.2026.107655

Interpretive Summary: In this study of >300 male and female adults ranging in age and body mass index (BMI), we tested (1) whether men and women differ in the salivary cortisol response to a mixed macronutrient meal after an overnight fast, (2) if these differences in postprandial (PP) cortisol explain variation in cardiovascular reactivity later in the day, and (3) whether postprandial cortisol mediates sex-based differences in cardiovascular reactivity following an emotion-recall task. Findings imply that regulation of circulating cortisol after the first meal of the day may influence downstream cardiovascular, autonomic nervous system, and mood status. Differences between males and females in this meal-affiliated drop in cortisol may also partially determine some of the observed sex-related differences in cardiovascular function.

Technical Abstract: Background. Circulating cortisol concentrations are connected to diet and the neurological systems that regulate food intake. After an overnight fast, skipping breakfast or the first meal of the day can diminish the typical drop in circulating cortisol concentrations, which helps to maintain energy demands under prolonged fasting. Objective. Determine (1) whether overnight fasted males and females differ in salivary cortisol dynamics after consuming a high-fat mixed macronutrient meal (2) if these differences in postprandial (PP) cortisol explain variation in cardiovascular function later in the day, and (3) whether PP cortisol mediates sex-based differences in cardiovascular status. Methods. This study had a cross-sectional design that examined >300 male and female participants. The recruitment sampling scheme consisted of sex (2 levels consisting of male and female) x age (3 levels consisting of 18-33, 34-49, and 50-65 years) x BMI (3 levels consisting of normal weight 18.5-24.99, overweight 25-29.99, and obese 30-39.99 kg/m2). The study test visit was conducted at the USDA – Western Human Nutrition Research Center (WHNRC) and included a mixed macronutrient test meal, an emotion-induction (anger recall) task, and the collection of blood, saliva, self-reported mood, and physiological information under the fasted, PP, and post-anger recall conditions. This study was approved by the University of California, Davis Institutional Review Board and is registered at clinicaltrials.gov (NCT02367287). Results. After an overnight fast and in response to the test meal, the drop in PP salivary cortisol was significantly (Ptime x sex = 0.00008) steeper in females vs. males. Fasting salivary cortisol did not differ (P = 0.620) between males and females, but females displayed significantly lower cortisol concentrations at 30 (P < 0.007), 60 (P < 0.005), and 90 (P < 0.010) min after consuming the test meal. Higher PP cortisol concentrations associated with elevated anger-induced heart rate (HR) (Beta = 0.050 ± 0.022; P = 0.0232), elevated anger-induced sympathetic tone (SNStone), as suggested by a greater change in tonic skin conductance (Beta = .232 ± .105; P = 0.0282), and lower endothelial function (EF), as suggested by a lower reactive hyperemia index (Beta = -.1637 ± .0698; P = 0.0197). EF, and anger-induced HR and SNStone differed between males and females, with variation in PP salivary cortisol partially explaining these sex-based differences. Conclusions. The magnitude of cortisol decline after consuming the first daily meal (e.g., breakfast) may contribute to sex-based differences in downstream cardiovascular reactivity.