Study of the Effect of a Very-Low-Carbohydrate Diet on Energy Expenditure

NCT01967563 | Terminated

• 2 other identifiers: 13021213-DK-0212
• Study Type: observational
• Target: 5
• Locations: 1 country
• Sites: 1

Brief Summary

Background: \- Popular weight loss plans often restrict carbohydrates or fat. Research shows that very-low-carbohydrate (ketogenic) diets lead to greater weight loss than low-fat diets. Researchers want to know if eating fewer carbohydrates changes the number of calories the body uses. They also want to know how a ketogenic diet affects hunger, hormones, and food preferences. Objectives: \- To better understand how the body responds to different diets. Eligibility: \- Men 18 to 50 years old who are healthy but overweight. Design:

• After screening, for 1 week, participants will visit the clinic daily to receive that day s food. They will not eat or drink anything else except water.
• Then participants will stay at the clinic for 8 weeks. They cannot leave but can have visitors. Participants will wear physical activity monitors, bike daily, and follow different diets. Tests will be given daily, and may include weighing, X-rays, and blood and urine tests. They will spend several days in a monitored room to test oxygen and carbon dioxide.

Conditions

Obesity; Appetite; Healthy Volunteers

Keywords

Energy Expenditure; Obesity; Carbohydrate; Fat; Ketones; Natural History

Outcome Measures

Primary Outcomes (1)

• To determine 24hr energy expenditure, respiratory quotient, and sleeping energy expenditure following a 4-week eucaloric ketogenic diet as compared to 4 weeks of consuming an energy-balanced standard diet.

  the subjects will spend the 4th, 5th, 11th, 12th, 18th, 19th, 25th and 26th days of Stages 2 \& 3 in the metabolic chamber to measure 24-hour energy expenditure and sleeping energy expenditure. The energy expenditure calculations will be corrected for urinary ketone excretion since approximately 0.33 L of O2 is consumed for every gram of ketone excreted in the urine.

  1 year

Secondary Outcomes (2)

• To investigate changes in body composition and appetitive behaviors such as hunger, satiety, food impulsivity, and food liking & wanting during a 4-week eucaloric ketogenic diet as compared to 4 weeks of consuming an energy-balanced stan...

  7 days(outpatient) plus 8 weeks( inpatient)

• To determine body weight and body composition following a 4-week eucaloric ketogenic diet as compared to 4 weeks of consuming an energy-balanced standard diet.

  7 days (outpatient) plus 8 weeks (inpatient)

Study Arms (1)

overweight and class I obese adult male volunteers

Adult Male Subjects will be recruited to determine the effects on energy expenditure of transitioning from an energy-and macronutrient-balanced standard baseline diet to a eucaloric ketogenic diet

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: male
• Healthy Volunteers: No
• Age Groups: Adult (18-64)
• Sampling Method: Probability Sample

Study Population

We will study the magnitude and variability of energy expenditure changes in response to a eucaloric ketogenic diet subsequent to a standard energy- and macronutrient-balanced diet in overweight and class I obese adult male volunteers

You may qualify if:

• Age 18-50 years, male
• Weight stable (\< 5 % over past 6 months)
• Current stable weight no more than 8% below lifetime maximum weight
• Body mass index (BMI) greater than or equal to 25 kg/m(2) but less than 35 kg/m(2), with each study site recruiting an equal number of subjects from the overweight range of 25 kg/m(2) less than or equal to BMI \< 30 kg/m(2) and from the class I obese range of 30 kg/m(2) less than or equal to BMI \< 35 kg/m(2)
• Otherwise healthy, as determined by medical history and laboratory tests
• Able to complete daily bouts of stationary cycling at a moderate rate and intensity
• Written informed consent
• Willing to eat all the food provided in the study
• Willing to continue consistently their habitual caffeine intake

You may not qualify if:

• BMI \< 25 kg/m(2) or greater than or equal to 35 kg/m(2)
• Blood pressure \> 140/90 mm Hg
• Evidence of metabolic or cardiovascular disease, or disease that may influence metabolism (e.g. cancer, diabetes, thyroid disease)
• Taking any prescription medication or other drug that may influence metabolism (e.g. diet/weight-loss medication, asthma medication, blood pressure medication, psychiatric medications, corticosteroids, or other medications at the discretion of the PI and/or study team)
• Hematocrit \< 40%
• Participating in a regular exercise program (\> 2h/week of vigorous activity)
• Dietary carbohydrate less than 30% or greater than 65% of total calories as determined by food frequency questionnaire
• Caffeine consumption \> 300 mg/day
• Regular use of alcohol (\> 2 drinks per day), tobacco (smoking or chewing) amphetamines, cocaine, heroin, or marijuana over past 6 months
• Past or present history of eating disorder (including binge eating) or psychiatric disease, including claustrophobia since part of the protocol will involve being confined to a small room for whole-body indirect calorimetry
• Volunteers with strict dietary concerns (e.g. vegetarian or kosher diet, multiple food allergies)
• Volunteers unwilling or unable to give informed consent

Sponsors & Collaborators

• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK): lead
• Pennington Biological Research Center: collaborator
• Translational Research Institute for Metabolism and Diabetes: collaborator
• Columbia University, New York, NY: collaborator

Study Sites (1)

National Institutes of Health Clinical Center

Bethesda, Maryland, 20892, United States

Location

Related Publications (4)

• Rosenbaum M, Hall KD, Guo J, Ravussin E, Mayer LS, Reitman ML, Smith SR, Walsh BT, Leibel RL. Glucose and Lipid Homeostasis and Inflammation in Humans Following an Isocaloric Ketogenic Diet. Obesity (Silver Spring). 2019 Jun;27(6):971-981. doi: 10.1002/oby.22468. Epub 2019 May 8.

  PMID: 31067015 DERIVED

• Hall KD, Guo J, Chen KY, Leibel RL, Reitman ML, Rosenbaum M, Smith SR, Ravussin E. Methodologic considerations for measuring energy expenditure differences between diets varying in carbohydrate using the doubly labeled water method. Am J Clin Nutr. 2019 May 1;109(5):1328-1334. doi: 10.1093/ajcn/nqy390.

  PMID: 31028699 DERIVED

• Koppel N, Bisanz JE, Pandelia ME, Turnbaugh PJ, Balskus EP. Discovery and characterization of a prevalent human gut bacterial enzyme sufficient for the inactivation of a family of plant toxins. Elife. 2018 May 15;7:e33953. doi: 10.7554/eLife.33953.

  PMID: 29761785 DERIVED

• Hall KD, Chen KY, Guo J, Lam YY, Leibel RL, Mayer LE, Reitman ML, Rosenbaum M, Smith SR, Walsh BT, Ravussin E. Energy expenditure and body composition changes after an isocaloric ketogenic diet in overweight and obese men. Am J Clin Nutr. 2016 Aug;104(2):324-33. doi: 10.3945/ajcn.116.133561. Epub 2016 Jul 6.

  PMID: 27385608 DERIVED

Related Links

• NIH Clinical Center Detailed Web Page

MeSH Terms

Conditions

Obesity; Platelet Glycoprotein IV Deficiency; Ketosis

Condition Hierarchy (Ancestors)

Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Acidosis; Acid-Base Imbalance; Metabolic Diseases

Study Officials

• Kevin Hall, Ph.D.

  National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: NIH
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: October 22, 2013
• First Posted: October 23, 2013
• Study Start: December 3, 2013
• Primary Completion: February 23, 2015
• Study Completion: February 23, 2015
• Last Updated: April 22, 2025

Record last verified: 2025-04

Locations

US (1)