Dairy Foods and Weight Loss

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: NCT00858312
Recruitment Status : Completed
First Posted : March 9, 2009
Last Update Posted : October 23, 2009
Iowa State University
Information provided by:
USDA, Western Human Nutrition Research Center

Brief Summary:
Obesity is a national epidemic with multiple causes and complex solutions. Research in both animals and humans has suggested that the inclusion of dairy foods into a moderate calorie restricted diet can increase weight loss and fat loss. Our proposed project extends these prior findings by determining, for the first time, how inclusion of dairy in a calorie-restricted diet changes the amount of visceral adiposity in overweight and obese subjects. The investigators also propose unique studies to evaluate the potential mechanism(s) by which dairy promotes weight and fat loss during dieting, through an examination of adipocyte size, gene expression, and inflammatory markers. The hypotheses under investigation are (1) that inclusion of dairy foods in a modest energy restricted diet will significantly increase body fat loss compared to a control diet; (2) that dairy products in a modest energy restricted diet will result in greater fat loss from intra-abdominal adipose tissue compared to the control, 3) components of dairy products up- or down-regulate the secretion of metabolically-relevant hormones during the postprandial and inter-meal periods, 4) dairy products will promote satiety and/or satiation, 5) dairy foods reduce adipocyte differentiation and/or enhance adipocyte apoptosis, leading to concomitant white adipose tissue (WAT) expression changes for genes playing a role in these processes, 6) dairy foods will reduce adipocyte lipid storage and enhance pathways associated with thermogenesis and mitochondrial function in WAT, as reflected in gene expression changes and reduced adipocyte size, and 7) dairy foods included in a modest energy restricted diet will decrease inflammation in WAT and other tissues, thus decreasing circulating cytokines, increasing zinc status, decreasing expression of inflammatory markers in WAT, and reducing WAT macrophage infiltration.

Condition or disease Intervention/treatment Phase
Overweight and Obesity Other: high dairy diet Other: Low Dairy Phase 2 Phase 3

Detailed Description:
84 overweight and overweight and obese adult males and females will be recruited from the faculty, staff, and student populations at UC-Davis as well as the greater Davis and Sacramento communities. Each intervention arm will require 42 adults; 35 for statistical power on weight loss + 14 more for attrition during the weight loss intervention. Statistical power for fat loss requires only 20 subjects/treatment arm. Subjects will be enrolled in 7 cohorts of 12 each and will be randomly assigned to either control or dairy diets. Subjects will meet the following additional inclusion and exclusion criteria:

Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 72 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: Role of Dairy Foods to Enhance Central Fat and Weight Loss With Moderate Energy Restriction in Overweight and Obesity Individuals
Study Start Date : October 2006
Actual Primary Completion Date : August 2009
Actual Study Completion Date : August 2009

Resource links provided by the National Library of Medicine

U.S. FDA Resources

Arm Intervention/treatment
Experimental: 1
Diet with 3-4 servings of dairy-rich foods/day
Other: high dairy diet
12 week energy restriction with 3-4 servings of dairy foods/day.
Placebo Comparator: 2
Low Dairy < 1 serving of dairy food/day
Other: Low Dairy
less than 1 serving of dairy foods per day.

Primary Outcome Measures :
  1. Weight loss, body fat loss, and reduction in intra-abdominal adipose tissue [ Time Frame: 12 weeks ]

Secondary Outcome Measures :
  1. Changes in metabolic hormones, e.g. leptin, grehlin, amylin PYY, CCK, insulin GLP-1, GIP [ Time Frame: 12 weeks ]

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Ages Eligible for Study:   20 Years to 50 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Body mass index (BMI) 28 -3 4.9 kg/m2
  • Age 25-45 years
  • Low calcium diet (determined by food frequency and diet history): < 1 serving of dairy foods and total dietary Ca intake from all sources not to exceed 600 mg/d .
  • No more than 3 kg weight loss during past three months
  • Negative pregnancy test at entry prior to DXA and abdominal CT scan; pregnancy testing will be repeated done at 6 weeks of diet intervention to insure that women do not become pregnant during the energy restriction period. Should a woman become pregnant she will be dismissed from the protocol. Pregnancy testing will also be done at the end of the study prior to DXA and abdominal CT scans

Exclusion Criteria:

  • BMI<28or>37. BMI greater than 37 indicates another level of obesity and the potential for numerous obesity related endocrine changes and substrate utilization abnormalities.

    • Type II diabetes requiring the use of any oral anti-diabetic agent and/or insulin (because of confounding effects on body weight regulation).
    • Fasting glucose > 110 mg/dl.
    • Adverse response to study foods (lactose intolerance, dairy intolerance, dairy allergy; this will be determined by self-report.
    • High calcium diet (determined by food frequency and diet history): Greater than 600 mg calcium per day from all sources (Ca supplements, dairy foods and other dietary sources).
    • History or presence of significant metabolic disease which could impact on the results of the study (i.e. endocrine, hepatic, renal disease).
    • Use of hypertension or lipid altering medications.
    • Resting blood pressure > 160/100 mg/Hg
    • Total cholesterol > 300mg/dl or triglyceride value > 400 mg/dl or LDL > 160 mg/dl.
    • History of eating disorder
    • Presence of active gastrointestinal disorders such as malabsorption syndromes
    • Pregnancy or lactation
    • Use of obesity pharmacotherapeutic agents within the last 12 weeks
    • Use of over-the-counter anti-obesity agents (e.g. those containing phenylpropanalamine, ephedrine and/or caffeine) within the last 12 weeks
    • Use of calcium supplements in the past 12 weeks
    • Recent (past four weeks) initiation of an exercise program
    • Recent (past twelve weeks) initiation of hormonal birth control or change in hormonal birth control regimen
    • Use of tobacco products.
    • Exercise more than 30 minutes/day - greater than this may influence substrate utilization.

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): NCT00858312

United States, California
Western Human Nutrition Research Center
Davis, California, United States, 95616
Sponsors and Collaborators
USDA, Western Human Nutrition Research Center
Iowa State University
Principal Investigator: Marta D Van Loan, Ph.D. USDA, ARS, Western Human Nutrition Research Center

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Marta Van Loan, USDA, ARS, Western Human Nutrition Research Center Identifier: NCT00858312     History of Changes
Other Study ID Numbers: FL49
First Posted: March 9, 2009    Key Record Dates
Last Update Posted: October 23, 2009
Last Verified: October 2009

Keywords provided by USDA, Western Human Nutrition Research Center:
dairy foods
weight loss
fat loss
metabolic regulation

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