Preventing Obesity Using Novel Dietary Strategies

January 29, 2013 updated by: Frank M. Sacks, Brigham and Women's Hospital

Preventing Overweight Using Novel Dietary Strategies (Pounds Lost)

The purpose of this study is to test the effectiveness for weight loss and weight maintenance of four diets differing in macronutrient composition: moderate in fat (40 percent energy) with two different protein levels (15 percent and 25 percent), and low in fat (20 percent energy), also with 15 percent and 25 percent protein levels. The study is only accepting participants in the Boston, Massachusetts or Baton Rouge, Louisiana area. For further enrollment information in Boston or Baton Rouge, see Eligibility Criteria or Design Narrative.

Study Overview

Detailed Description

BACKGROUND:

Obesity is a growing problem whose importance is reflected in the resources that are expended each year by a large section of the population on weight reduction drugs and therapies. Although numerous weight loss diets are available, there is little agreement in the scientific literature or the lay press as to the amount of fat, protein, and carbohydrates that would comprise the most efficacious diet for weight loss and long term weight loss retention. Reliable information about the effectiveness of low calorie diets with differing macronutrient composition is clearly needed and of paramount importance to inform the choice of a weight reduction diet.

DESIGN NARRATIVE:

The study tests the effectiveness for weight loss and weight maintenance of four diets differing in macronutrient composition: moderate in fat (40% energy) with two different protein levels (15% and 25%), and low in fat (20% energy), also with 15% and 25% protein levels. The moderate-fat diet will be patterned after a Mediterranean diet. All four dietary approaches will be low in saturated fat, and will involve reduction in total energy intake. Each diet is deemed practical and suitable for public health recommendations, and each would be expected to have a favorable effect on cardiovascular disease risk factors. All participants will receive a state-of-the-art behavioral therapy program standardized across the two centers in Boston and Baton Rouge. An estimated 800 men and women, age 30-70 years, body mass index (BMI) 25-40 kg/m2, will be randomized among the 4 dietary treatments. The primary outcome variable will be change in total body weight from baseline to 2 years. Secondary outcomes related to obesity are body fat, BMI, waist circumference, visceral fat, and hepatic and skeletal muscle fat. Other outcomes are psychological factors (diet satisfaction, satiety, food craving, dietary restraint, disinhibition and hunger, and quality of life); major cardiovascular risk factors (blood pressure, low density lipoprotein [LDL] cholesterol, high density lipoprotein [HDL] cholesterol, and triglycerides); prevalence of the metabolic syndrome; blood glucose, insulin, and hemoglobin A1C; emerging cardiovascular risk factors (apolipoprotein B, VLDL and LDL particles with apolipoprotein C-III, lipoprotein[a]); microalbuminuria; and bone mineral content. The primary results will be straightforwardly applicable to public health and clinical guidelines for obesity and will increase our understanding of the biology of obesity and weight loss.

The study is only accepting participants in the Boston, Massachusetts or Baton Rouge, Louisiana area. For Boston participants, contact: 617-998-1047 or www.poundslost.org. For Baton Rouge participants, contact: schoensj@pbrc.edu or 225-763-2623.

Study Type

Interventional

Enrollment

811

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Louisiana
      • Baton Rouge, Louisiana, United States, 70808
        • Pennington Biomedical Reseach Center, Louisiana State University
    • Massachusetts
      • Boston, Massachusetts, United States, 02115
        • Harvard University School of Public Health

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

30 years to 70 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Only accepting participants in the Boston, Massachusetts or Baton Rouge, Louisiana area
  • Between the ages of 30 - 70
  • Willing to modify eating pattern according to instructions
  • Overweight or obese and in good health with a BMI of 25-40
  • Committed to a long-term weight loss and maintenance program
  • Willing to attend multiple weight loss group sessions
  • Willing to increase activity level

Exclusion Criteria:

  • Pregnant, planning to become pregnant, or are breastfeeding
  • Unwilling to participate in the schedule of group sessions and individual visits
  • Unstable or recent onset of heart disease or any other serious illness
  • Cannot change diet due to medical or other reasons
  • Planning to leave the area prior to the anticipated end of participation
  • Current participation in another clinical trial with an intervention that affects weight change
  • Have diabetes that is treated with insulin or hypoglycemic oral medicines
  • Diagnosis of psychiatric or emotional problems within 6 months of study
  • Currently have an eating disorder
  • Have hypothyroidism
  • Have an unstable weight

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Change in body weight (measured at Year 2)

Secondary Outcome Measures

Outcome Measure
Body fat
BMI
Waist circumference
Visceral fat
Hepatic and skeletal muscle
Psychological factors from diet
Major cardiovascular risk factors
Prevalence of the metabolic syndrome (measured at Year 2)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

September 1, 2003

Primary Completion (Actual)

December 1, 2007

Study Completion (Actual)

December 1, 2007

Study Registration Dates

First Submitted

November 13, 2003

First Submitted That Met QC Criteria

November 14, 2003

First Posted (Estimate)

November 17, 2003

Study Record Updates

Last Update Posted (Estimate)

January 30, 2013

Last Update Submitted That Met QC Criteria

January 29, 2013

Last Verified

January 1, 2013

More Information

Terms related to this study

Other Study ID Numbers

  • 1238
  • U01HL073286 (U.S. NIH Grant/Contract)

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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