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Alternate Day Fasting for Weight Loss, Weight Maintenance and Cardio-protection

This study has been completed.
Pennington Biomedical Research Center
National Heart, Lung, and Blood Institute (NHLBI)
Information provided by (Responsible Party):
Krista Varady, University of Illinois at Chicago Identifier:
First received: August 14, 2009
Last updated: January 11, 2016
Last verified: January 2016
The proposed research will demonstrate that alternate day modified fasting (ADMF) is a suitable alternative to daily calorie restriction (CR) for weight loss, weight maintenance, and heart disease prevention. Since many overweight and obese individuals find it difficult to adhere to daily CR, this diet option may improve adherence with these dietary restriction protocols. This, in turn, will allow a greater percent of the overweight and obese population to lose weight, maintain weight loss, and prevent future occurrences of coronary heart disease.

Condition Intervention
Coronary Heart Disease
Weight Loss
Other: Alternate day fasting
Other: Calorie restriction
Other: Control diet

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Prevention
Official Title: Alternate Day Fasting for Weight Loss, Weight Maintenance and Cardio-protection

Resource links provided by NLM:

Further study details as provided by University of Illinois at Chicago:

Primary Outcome Measures:
  • Body weight [ Time Frame: Weekly ]
  • Change in total energy expenditure [ Time Frame: Baseline and month 6 ]
    Total energy expenditure will be measured for each subject using the doubly labeled water stable isotope technique at baseline and month 6.

Secondary Outcome Measures:
  • Change in plasma lipid concentrations [ Time Frame: 4-week intervals up to 48 weeks ]
  • Change in systolic and diastolic blood pressure [ Time Frame: 4-week intervals up to 48 weeks ]
  • Change in heart rate [ Time Frame: 4-week intervals up to 48 weeks ]
  • Change in fasting glucose [ Time Frame: 4-week intervals up to 48 weeks ]
  • Change in fasting insulin [ Time Frame: 4-week intervals up to 48 weeks ]
  • Change in insulin resistance measured by HOMA-IR [ Time Frame: 4-week intervals up to 48 weeks ]
  • Change in plasma homocysteine concentrations [ Time Frame: 4-week intervals up to 48 weeks ]
  • Change in plasma C-reactive protein concentrations [ Time Frame: 4-week intervals up to 48 weeks ]

Enrollment: 100
Study Start Date: September 2010
Study Completion Date: January 2015
Primary Completion Date: January 2015 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Alternate day fasting (ADF)
Fast day diet: 25% energy intake, Feast day diet: Ad libitum energy intake (alternating days)
Other: Alternate day fasting
Experimental: Calorie restriction (CR)
75% energy intake every day
Other: Calorie restriction
Active Comparator: Control
Usual diet
Other: Control diet

Detailed Description:
Overweight and obese individuals are at increased risk for coronary heart disease (CHD). Losing weight by means of dietary restriction greatly reduces vascular disease risk. The majority of studies examiningmost common dietary restriction protocol s implemented is daily calorie restriction (CR). Another dietary restriction regimen employed, although far less commonly, is alternate day modified fasting (ADMF). ADMF involves a "feed day" where food is consumed ad-libitum, alternated with a "fast day", where food intake is partially reduced. Previous reports show that adherence to ADMF exceeds that of CR after 8 weeks of treatment. This increased adherence to ADMF results in greater weight loss, which produces more pronounced improvements in CHD risk. What has yet to be determined is whether adherence to ADMF remains near maximal for longer treatment durations (24 weeks), and if this improved adherence results in greater reductions in body weight and CHD risk, versus CR. Once weight loss is achieved, weight maintenance is extremely important as CHD risk can increase if weight is regained. Whether ADMF is an effective strategy for weight maintenance remains unknown. Accordingly, the aims of this proposal are: Aim 1: To establish that adherence to ADMF is greater than that of CR during a 24-week intervention period and to determine if increased adherence to ADMF results in greater weight loss; Aim 2: To establish that greater reductions in body weight by ADMF over a 24-week period will result in greater improvements in traditional CHD risk parameters (blood pressure, plasma lipid levels, cholesterol synthesis rate, LDL particle size, and CRP) and emerging CHD risk parameters (fat cell-derived hormones, body fat distribution, and fat cell size) in comparison to CR; and Aim 3: To establish that ADMF is an effective diet therapy to maintain weight loss and sustain improvements in CHD risk indicators, and to compare changes in cognitive and behavioral components of eating between ADMF and CR subjects. A 52-week randomized, controlled, parallel-arm feeding trial will be implemented to test these objectives. The trial will be divided into 3 consecutive intervention periods: (1) 4-week baseline; (2) 24-week weight loss with food provided; and (3) 24-week weight maintenance with no food provided. Overweight and obese subjects (n = 90) will be randomized to 1 of 3 groups: (1) ADMF, 75% energy restriction on the "fast day" and ad libitum fed on the "feed day"; (2) CR, 25% restriction everyday; or 3) control, 100% energy intake everyday. During the weight maintenance phase, ADMF subjects will consume 25% of their energy needs on the "fast day" and 175% of their needs on the "feed day", while CR and control subjects will consume 100% of their needs everyday. Our findings will show that ADMF can be implemented as an alternative to CR to help overweight and obese individuals lose weight, maintain weight loss, and sustain reductions in CHD risk. This study will also generate insights into the specific behavioral changes that occur with ADMF that explain why ADMF is a successful diet strategy for weight maintenance.

Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion criteria. Adult subjects meeting the following criteria will be eligible to participate:

  • Age between 18 to 65 years old
  • BMI between 25.0 and 39.9 kg/m2
  • Previously sedentary (<60 minutes/week of light activity corresponding to 2.5 to 4.0 metabolic equivalents (METs) for the 3 months prior to the study)

Exclusion criteria. Subjects excluded from participating in the study include those who:

  • Have a history cardiovascular disease (prior angina, myocardial infarction or stroke)
  • Are diabetic (fasting blood glucose > 126 mg/dl)
  • Have a history of psychiatric disorders and/or eating disorders
  • Are taking anti-depressant or anti-anxiety medications
  • Are taking drugs that affect study outcomes (weight loss, lipid-lowering, or blood pressure drugs)
  • Are not weight stable for 3 months prior to the beginning of study (weight gain or loss > 4 kg)
  • Are not able to keep a food diary or activity log for 7 consecutive days during screening
  • Are perimenopausal or have an irregular menstrual cycle (menses that does not appear every 27-32 days)
  • Are claustrophobic or have implanted electrical devices (cardiac pacemaker or a neurostimulator)
  • Are pregnant, or trying to become pregnant
  • Are smokers
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Please refer to this study by its identifier: NCT00960505

United States, Illinois
University of Illinois, Chicago
Chicago, Illinois, United States, 60622
Sponsors and Collaborators
University of Illinois at Chicago
Pennington Biomedical Research Center
National Heart, Lung, and Blood Institute (NHLBI)
Principal Investigator: Krista Varady, PhD University of Illinois, Chicago
  More Information

Responsible Party: Krista Varady, Associate Professor, University of Illinois at Chicago Identifier: NCT00960505     History of Changes
Other Study ID Numbers: 2010-0118
R01HL106228 ( US NIH Grant/Contract Award Number )
Study First Received: August 14, 2009
Last Updated: January 11, 2016

Keywords provided by University of Illinois at Chicago:
Coronary heart disease
Weight loss
Weight maintenance

Additional relevant MeSH terms:
Body Weight
Heart Diseases
Weight Loss
Coronary Disease
Coronary Artery Disease
Myocardial Ischemia
Signs and Symptoms
Cardiovascular Diseases
Body Weight Changes
Vascular Diseases
Arterial Occlusive Diseases processed this record on April 28, 2017