Dairy Foods and Weight Loss

NCT ID: NCT00858312

Last Updated: 2025-03-14

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Clinical Phase

NA

Total Enrollment

78 participants

Study Classification

INTERVENTIONAL

Study Start Date

2006-10-31

Study Completion Date

2009-08-31

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

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.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

84 overweight and overweight and obese adult males and females will be recruited from the faculty, staff, and student populations at University of California-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:

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Overweight and Obesity

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

RANDOMIZED

Intervention Model

PARALLEL

Primary Study Purpose

BASIC_SCIENCE

Blinding Strategy

NONE

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

1

Diet with 3-4 servings of dairy-rich foods/day

Group Type EXPERIMENTAL

high dairy diet

Intervention Type OTHER

12 week energy restriction with 3-4 servings of dairy foods/day.

2

Low Dairy \< 1 serving of dairy food/day

Group Type PLACEBO_COMPARATOR

Low Dairy

Intervention Type OTHER

less than 1 serving of dairy foods per day.

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

high dairy diet

12 week energy restriction with 3-4 servings of dairy foods/day.

Intervention Type OTHER

Low Dairy

less than 1 serving of dairy foods per day.

Intervention Type OTHER

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* Body mass index (BMI) 28 -3 4.9 kg/m2
* Age 20-45 years for females, age 20-50 for males
* 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 phenylpropanolamine, 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.
Minimum Eligible Age

20 Years

Maximum Eligible Age

50 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

Yes

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

Iowa State University

OTHER

Sponsor Role collaborator

USDA, Western Human Nutrition Research Center

FED

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Responsibility Role SPONSOR

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

Marta D Van Loan, Ph.D.

Role: PRINCIPAL_INVESTIGATOR

USDA, ARS, Western Human Nutrition Research Center

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

Western Human Nutrition Research Center

Davis, California, United States

Site Status

Countries

Review the countries where the study has at least one active or historical site.

United States

References

Explore related publications, articles, or registry entries linked to this study.

Van Loan MD, Keim NL, Adams SH, Souza E, Woodhouse LR, Thomas A, Witbracht M, Gertz ER, Piccolo B, Bremer AA, Spurlock M. Dairy Foods in a Moderate Energy Restricted Diet Do Not Enhance Central Fat, Weight, and Intra-Abdominal Adipose Tissue Losses nor Reduce Adipocyte Size or Inflammatory Markers in Overweight and Obese Adults: A Controlled Feeding Study. J Obes. 2011;2011:989657. doi: 10.1155/2011/989657. Epub 2011 Sep 14.

Reference Type BACKGROUND
PMID: 21941636 (View on PubMed)

Witbracht MG, Laugero KD, Van Loan MD, Adams SH, Keim NL. Performance on the Iowa Gambling Task is related to magnitude of weight loss and salivary cortisol in a diet-induced weight loss intervention in overweight women. Physiol Behav. 2012 May 15;106(2):291-7. doi: 10.1016/j.physbeh.2011.04.035. Epub 2011 Apr 30.

Reference Type BACKGROUND
PMID: 21565212 (View on PubMed)

Witbracht MG, Van Loan M, Adams SH, Keim NL, Laugero KD. Dairy food consumption and meal-induced cortisol response interacted to influence weight loss in overweight women undergoing a 12-week, meal-controlled, weight loss intervention. J Nutr. 2013 Jan;143(1):46-52. doi: 10.3945/jn.112.166355. Epub 2012 Nov 28.

Reference Type BACKGROUND
PMID: 23190756 (View on PubMed)

Piccolo BD, Dolnikowski G, Seyoum E, Thomas AP, Gertz ER, Souza EC, Woodhouse LR, Newman JW, Keim NL, Adams SH, Van Loan MD. Association between subcutaneous white adipose tissue and serum 25-hydroxyvitamin D in overweight and obese adults. Nutrients. 2013 Aug 26;5(9):3352-66. doi: 10.3390/nu5093352.

Reference Type BACKGROUND
PMID: 24067385 (View on PubMed)

Piccolo BD, Keim NL, Fiehn O, Adams SH, Van Loan MD, Newman JW. Habitual physical activity and plasma metabolomic patterns distinguish individuals with low vs. high weight loss during controlled energy restriction. J Nutr. 2015 Apr;145(4):681-90. doi: 10.3945/jn.114.201574. Epub 2015 Jan 28.

Reference Type BACKGROUND
PMID: 25833772 (View on PubMed)

Krishnan S, Adams SH, Witbracht MG, Woodhouse LR, Piccolo BD, Thomas AP, Souza EC, Horn WF, Gertz ER, Van Loan MD, Keim NL. Weight Loss, but Not Dairy Composition of Diet, Moderately Affects Satiety and Postprandial Gut Hormone Patterns in Adults. J Nutr. 2021 Jan 4;151(1):245-254. doi: 10.1093/jn/nxaa327.

Reference Type DERIVED
PMID: 33245130 (View on PubMed)

Piccolo BD, Hall LM, Stephensen CB, Gertz ER, Van Loan MD. Circulating 25-Hydroxyvitamin D Concentrations in Overweight and Obese Adults Are Explained by Sun Exposure, Skin Reflectance, and Body Composition. Curr Dev Nutr. 2019 May 27;3(7):nzz065. doi: 10.1093/cdn/nzz065. eCollection 2019 Jul.

Reference Type DERIVED
PMID: 31304455 (View on PubMed)

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

DMI

Identifier Type: -

Identifier Source: secondary_id

FL49

Identifier Type: -

Identifier Source: org_study_id

More Related Trials

Additional clinical trials that may be relevant based on similarity analysis.

Dairy Fat and Fermentation Study
NCT05840081 COMPLETED NA
Dairy Lipids and Cardiometabolic Risk
NCT05783466 RECRUITING NA