Association of chrono-nutrition components with cardiometabolic health in a sample of Iranian adults: a cross-sectional study.

Chrono-nutrition is an emerging field that examines how the frequency and timing of meals impact health. Previous research shows inconsistency in the relationship between chrono-nutritional components and cardiometabolic health. We investigated cross-sectional associations between these components and cardiometabolic health in 825 Iranian adults aged 20-59 years. Dietary data, including the number of eating occasions (EOs), meal timing, and meal irregularity of energy intake, were collected using three 24-hour dietary recalls. Anthropometric measurements, blood pressure, and laboratory tests (fasting plasma glucose, lipid profile, insulin, uric acid, and c-reactive protein) were conducted. Insulin resistance and sensitivity (HOMA-IR, HOMA-IS), the triglyceride-glucose, the lipid accommodation product and body mass index (BMI) were calculated. The demographic and morning-evening questionnaire (MEQ) was completed. General linear regression was used to assess associations between chrono-nutritional components and outcomes. Interactions with age and BMI were examined in all associations. Chrono-nutrition components were not significantly related to cardiometabolic risk factors in the total population. However, a lower number of EOs was associated with an increased LDL/HDL-C ratio (β (95% CI): 0.26 (0.06-0.48)) among overweight and obese participants. Additionally, less irregularity in breakfast energy intake was associated with a lower total cholesterol/HDL-C ratio (-0.37 (-0.95 to -0.18)) and a lower LDL-C/HDL-C ratio (-0.32 (-0.79 to -0.13)) among participants with a normal BMI (all p < 0.05). The study concluded that more frequent meals, and regular energy intake might enhance cardiometabolic health cross-sectionally, highlighting the need for prospective studies to further investigate these associations and the mediating role of BMI.