Nighttime Synchrony of Your Nutrition and Circadian Health

Inclusion Criteria: 1. Age: 18-35 years old; equal numbers of men and women 2. Body Mass Index (BMI): 18.5-24.9 kg/m2 3. Sleep Habits: habitual self-reported average total sleep time (TST) 7-9 hours per night for prior 6 months Exclusion Criteria: 1. Clinically diagnosed sleep disorder or apnea hypopnea index (AHI) ≥5 2. Evidence of significant organ system dysfunction or disease (e.g., heart disease, diabetes) 3. Fasting plasma glucose ≥100 mg/dL 4. Major psychiatric illness (e.g., major depressive disorder) 5. Cancer that has been in remission less than 5 years 6. History of shift-work in prior year 7. Weight change \>5% of body weight over prior six months 8. Currently following a weight-loss program 9. Menopause 10. Pregnant/nursing 11. Greater than 5-day variation in menstrual cycle length month-to-month 12. Currently smoking 13. Alcohol intake \>14 drinks/week or \>3 drinks/day. 14. Use of prescription medications (except oral contraceptives) within one month prior to or during in-lab visits. 15. Consumption of illegal drugs or \>500mg per day of caffeine.