Night Owl Metabolism: Investigating the Impact of Chronotype on Glucose Metabolism in Youth

Summary

The proposed study uses a novel and rigorous randomized cross-over study design in youth (17-23y) with late and non-late chronotype (n=35 per group) to assess the glycemic effect of "aligning" an oral glucose tolerance test (OGTT) or first-meal of day to a subject's chronotype. Both groups will undergo 2 OGTTs (aligned and mis-aligned with chronotype) to compare glucose tolerance and insulin sensitivity within-subject (primary outcome) and between groups (Aim 1). Then, youth will also undergo two standardized meals (aligned and mis-aligned with chronotype) while wearing continuous glucose monitoring to compare post-prandial glucose excursions within-subject and between groups (Aim 2). A pilot Exploratory Aim 3 (n=12 per group) will investigate delayed melatonin patterns under dim-light as a potential pathophysiologic mechanism behind abnormal glucose tolerance in youth with late chronotype on morning OGTTs.

Eligibility

Age range

18–23 years

Sex

All

Healthy volunteers

Yes

Interventions

• Diagnostic Test
  Timing of OGTT

  In Aim 1, timing of oral glucose tolerance test will be altered.

• Behavioral
  Timing of Standardized Meal

  In Aim 2, timing of a standardized meal will be altered.

Location