Home Sleep and Metabolism

Inclusion Criteria:

- Age: 21-40 years

- Body mass index: 25.0 to 29.9 kg/m2

- Average habitual sleep duration of 6.5 hours or less per night (as confirmed by
actigraphy)

- stable sleep habits for the past 6 months

Exclusion Criteria:

- obstructive sleep apnea or history of any other sleep disorder

- night or rotating shift work (current or in the past 2 years)

- habitual daytime naps

- recent (< 4 week) travel across time zones

- extreme chronotypes

- any acute or chronic medical condition

- diabetes

- prior or current eating or psychiatric disorders

- claustrophobia

- irregular menstrual periods, menopause, pregnancy,

- alcohol abuse, excessive caffeine intake, smoking, illegal drug use

- subjects who are currently following a weight loss regimen or any other special diet
or exercise programs

- subjects who have received iv or oral contrast in the past 2 weeks

- use of any prescription medication that can affect sleep or metabolism with the
exception of antihypertensive and lipid lowering agents as follows. Subjects who are
taking anti-hypertensive medication and/or lipid-lowering agents will be included only
if they are well controlled and on a stable regimen (no change in medications in the
previous 3 months). However, beta-blockers and thiazide diuretics will not be allowed,
as these medications are known to affect insulin sensitivity. Women will be required
to not be on hormone replacement therapy.