Sleep Restriction and Obesity

Study Overview
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Brief Summary
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Insufficient sleep may be one of the most common, and most preventable, obesity risk factors. The investigators wish to determine whether 14 nights of modest sleep restriction results in increased energy balance, thus potentially increasing the risk of obesity. The investigators hypothesize that sleep restriction will result in increased energy balance.

Detailed Description
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Numerous studies have reported that self-reported short sleep duration is associated with obesity and weight gain. Insufficient sleep may be one of the most common, and most preventable, obesity risk factors. Given that sleep restriction is largely voluntary and potentially correctable, understanding the mechanisms that link insufficient sleep to positive energy balance and the development of obesity, particularly visceral obesity, is crucial to clinical applications, public health policy, and informing future studies. The investigators wish to determine whether 14 nights of modest sleep restriction results in increased energy balance, thus potentially increasing the risk of obesity. The investigators will combine energy balance, biomarker, and imaging data with state-of-the art sleep monitoring to provide unambiguous data on the effects of sleep restriction on obesity. Together, the investigators findings will help explain whether the reduced sleep duration in the general population may be contributing to the current epidemic of obesity, and suggest strategies to reduce this risk.

Official Title
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Sleep Restriction and Obesity

Conditions
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Obesity

Intervention / Treatment
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* Behavioral: Sleep restriction


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18-40 years BMI of 18.5-30 kg/m2 Not a current smoker or tobacco user No chronic medical or psychiatric disorders On no prescription medications other than second generation antihistamines (cetirizine, fexofenadine, desloratadine, loratadine, etc), oral contraceptive pills, or intrauterine devices History of normal sleep patterns, defined as nocturnal sleep duration of 6.5-8 hours per night without regular daytime naps Exclusion Criteria: The investigators will exclude subjects who have any medical or psychiatric disorders History of anxiety or depression Those taking any medications other than non-sedating antihistamines or oral contraceptives will be excluded Those found to have depression on a depression screening tool (BDI-II) will be excluded Current smokers will be excluded All female subjects will undergoing a screening pregnancy test and excluded if positive Subjects found to have significant sleep disorders will be excluded

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Sleep restriction<br>Sleep restriction | Behavioral: Sleep restriction<br>* 14 days of sleep restriction, 4 hours of sleep per day.<br>|
| No Intervention: Normal sleep<br>Normal sleep | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in caloric intake and hunger | Change in caloric intake and hunger, measured during acclimation, experimental and recovery timepoints. | baseline to 21 days | 
| Change in energy expenditure | Change in energy expenditure, including activity energy expenditure, thermic effect of food (TEF), and basal metabolic rate (BMR), measured during acclimation, experimental and recovery timepoints.. | baseline to 21 days | 
| Change in fat tissue characteristics and body composition | Changes in fat tissue characteristics from serial fat biopsies, and in body composition from DEXA and CT imaging, measured during acclimation, experimental and recovery timepoints. | baseline to 21 days | 
| Change in metabolic hormones | Change in metabolic hormones measured during acclimation, experimental and recovery timepoints. | baseline to 21 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in neurocognitive deficits | Change in neurocognitive function measured by battery, measured during acclimation, experimental and recovery timepoints.. | baseline to 21 days | 
| Change in blood pressure and autonomic function | Change in mean arterial blood pressure and autonomic function, measured during acclimation, experimental and recovery timepoints. | baseline to 21 days | 
| Change in markers of inflammation and endothelial function | Change in markers of inflammation and endothelial function, measured during acclimation, experimental and recovery timepoints. | baseline to 21 days | 
| Change in electrocardiographic characteristics | Change in electrocardiographic characteristics, measured during acclimation, experimental and recovery timepoints. | baseline to 21 days | 
| Change in arterial stiffness | Change in arterial stiffness, measured during acclimation, experimental, and recovery timepoints. | baseline to 21 days | 
| Change in cardiovascular reactivity | Change in cardiovascular reactivity, measured during acclimation, experimental, and recovery timepoints. | baseline to 21 days |