Effects of Time of Sleep Restriction in Obesity

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01259895
Recruitment Status : Completed
First Posted : December 14, 2010
Last Update Posted : August 18, 2014
Associacao Fundo de Incentivo a Psicofarmcologia
Centro de Estudos em Sonolência e Acidentes
Information provided by (Responsible Party):
Iona Zalcman Zimberg, Federal University of São Paulo

Brief Summary:
The purpose of this study is to determine the effect of different time of sleep restriction on control of food intake and metabolism of obese and normal subjects.

Condition or disease
Obesity Sleep Restriction Appetite Regulation Eating

Detailed Description:

The reduction of sleep time has now become a common habit, driven by the demands and opportunities of modern society. Some studies have suggested that sleep restriction would be an important factor in predisposing to obesity. However studies of sleep restriction in obese individuals have not yet been conducted. Still, the time of sleep restriction varies greatly between studies, making it difficult to compare results.

The investigators aim to recruit 20 young adults, 10 obese and 10 normal weight individuals. The study will be conducted as a randomized, crossover study with three conditions. Each participant will be subjected to reduction of the beginning of sleep (from 3-7h), reduction of the end of sleep (from 23-3h), and normal sleep (from 23-7h), in random order, for three consecutive nights.

In each condition, subjects will stay for 4 days in the laboratory. Three control meals will be offered. Visual analogue scales will be applied before and after each meal to assess hunger and appetite for different food categories. Blood samples will be collected hourly during 24 hours.

Study Type : Observational
Actual Enrollment : 20 participants
Observational Model: Case-Crossover
Time Perspective: Cross-Sectional
Official Title: Effect os Sleep Restriction on Control of Food Intake and Metabolism of Obese Subjects
Study Start Date : February 2009
Actual Primary Completion Date : September 2011
Actual Study Completion Date : June 2012

BMI > 30kg/m2
Normal weight
BMI between 19 and 24,9kg/m2

Primary Outcome Measures :
  1. Appetite regulating hormones and stress hormones [ Time Frame: Measured every hour over the course of 24 hours on day 3 ]
    Hormones are sampled from blood

Secondary Outcome Measures :
  1. Hunger and satiety [ Time Frame: Measured every 4 hour over the course of 12 hours on day 2 and 3 ]
    Hunger and saciety are measured using visual analogue scales before and after breakfast, lunch and dinner meal

  2. Food intake [ Time Frame: measured each meal ]
    The meal will be weighted before and after the breakfast, lunch and dinner. Energy and nutrient intake are assessed from the amount of the meal consumed.

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Ages Eligible for Study:   20 Years to 35 Years   (Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
primary care clinic, community sample, residents of the city of Sao Paulo

Inclusion Criteria:

  • obese (BMI>30) and normal weight (BMI between 19 and 24,9)
  • regular time of sleep between 6.5 and 8 hours

Exclusion Criteria:

  • self-reported sleep problems (Pittsburgh Sleep Quality Index score >5);
  • Obstructive sleep apnea (AHI > 5 in polysomnography)
  • night work;
  • variable sleep habits or habitual daytime naps;
  • regular physical exercise (>3 hours/week);
  • excessive intake of alcohol (>7 drinks/week);
  • excessive intake of caffeine (>300 mg/day);
  • smoking;
  • substance abuse;
  • use of prescription medications or over-the-counter drugs affecting sleep or metabolism;
  • chronic diseases (e.g. cancer, asthma, back pain, thyroid disease, heart disease, diabetes, etc.)
  • history of neurological, medical or sleep disorders;
  • trans-meridian travelling the last month;
  • chronotype: extreme morning or extreme evening
  • unable to comply with the protocol.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01259895

Centro de Estudos em Psicobiologia e Exercicio (CEPE)
Sao Paulo, Brazil, 04020-060
Sponsors and Collaborators
Federal University of São Paulo
Associacao Fundo de Incentivo a Psicofarmcologia
Centro de Estudos em Sonolência e Acidentes
Principal Investigator: Marco Tulio de Mello, PhD Federal University of São Paulo

Additional Information:
Responsible Party: Iona Zalcman Zimberg, PhD student, Federal University of São Paulo Identifier: NCT01259895     History of Changes
Other Study ID Numbers: CEPE18
FAPESP2008/09565-2 ( Other Grant/Funding Number: FAPESP )
First Posted: December 14, 2010    Key Record Dates
Last Update Posted: August 18, 2014
Last Verified: August 2014

Additional relevant MeSH terms:
Nutrition Disorders
Body Weight
Signs and Symptoms