Metabolic and Bio-behavioral Effects of Following Recommendations in the Dietary Guidelines for Americans

NCT ID: NCT04293224

Last Updated: 2025-12-17

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 70 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2022-08-01
• Study Completion Date: 2026-09-30

Brief Summary

This study, at the Western Human Nutrition Research Center (WHNRC), will focus on whether or not achieving and maintaining a healthy body weight is the most important health promoting recommendation of the Dietary Guidelines for Americans (DGA).The investigators hypothesize that improvement in cardiometabolic risk factors resulting from eating a DGA style diet will be greater in people whose energy intake is restricted to result in weight loss compared to those who maintain their weight. The investigators further propose that during a state of energy restriction, a higher nutrient quality diet such as the DGA style diet pattern, will result in greater improvement in cardiometabolic risk factors compared to a typical American diet (TAD) pattern that tends to be lower nutrient quality (more energy-dense and less nutrient-rich.)

Detailed Description

This will be a 28-week study including pre-diet testing (week 1), an 8-week controlled feeding period, post-diet testing (week 10), a follow-up period of dietary education and observation, and end of study testing (week 28). During the 8 week feeding, participants will be randomly assigned one of the following diets:

1. DGA Mediterranean diet pattern at sufficient energy level to maintain body weight (energy balance)

2. DGA Mediterranean diet pattern at a moderately reduced energy level (negative energy balance)

3. TAD diet pattern at a moderately reduced energy level (negative energy balance)

In the follow-up phase, the investigators will evaluate how multiple factors may influence body weight management, including previous dietary exposure, as well as the role of cognitive function, executive function, genetics, habitual diet, physical activity, eating behavior, stress and stress responsivity, metabolic flexibility and gut microbiome.

Conditions

Obesity; Body Weight

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

DGA Mediterranean diet pattern, energy balance

Diet plan focused on energy balance (meets calorie needs), emphasizes fruits, vegetables and whole grains and limits calories from added sugars and saturated fats and reduces sodium intake per Dietary Guidelines for Americans (DGA) recommendations.

Group Type: EXPERIMENTAL

DGA Mediterranean diet pattern, energy balance

Intervention Type: OTHER

Foods and beverages will be provided for participants for eight weeks. During the controlled feeding portion of the study the DGA Mediterranean diet pattern will be based on the Table A7-1 of the 2015 Dietary Guidelines for Americans which outlines daily nutritional goals for age-sex groups based on Dietary Reference Intakes (DRI) and dietary guidelines recommendations.

DGA Mediterranean diet pattern, negative energy balance

Negative energy balance (\~25% calorie reduction compared to needs), emphasizes fruits, vegetables and whole grains and limits calories from added sugars and saturated fats and reduces sodium intake per Dietary Guidelines for Americans (DGA) recommendations.

Group Type: EXPERIMENTAL

DGA Mediterranean diet pattern, negative energy balance

Intervention Type: OTHER

Foods and beverages will be provided for participants for eight weeks. During the controlled feeding portion of the study the DGA Mediterranean diet pattern will be based on the Table A7-1 of the 2015 Dietary Guidelines for Americans which outlines daily nutritional goals for age-sex groups based on Dietary Reference Intakes (DRI) and dietary guidelines recommendations

TAD diet pattern

Typical American Diet (TAD) with negative energy balance (\~25% calorie reduction compared to needs) which mimics intake of fruits, vegetables, whole grains, added sugars, saturated fats and sodium based on data from What We Eat in America (WWEIA).

Group Type: EXPERIMENTAL

TAD diet pattern, negative energy balance

Intervention Type: OTHER

Foods and beverages will be provided for participants for eight weeks. During the controlled feeding portion of the study the be based on evidence collected from What We Eat in America (WWEIA) data. Based on this data the participants will be provided a diet that reflects American dietary trends.

Interventions

DGA Mediterranean diet pattern, energy balance

Foods and beverages will be provided for participants for eight weeks. During the controlled feeding portion of the study the DGA Mediterranean diet pattern will be based on the Table A7-1 of the 2015 Dietary Guidelines for Americans which outlines daily nutritional goals for age-sex groups based on Dietary Reference Intakes (DRI) and dietary guidelines recommendations.

Intervention Type: OTHER

DGA Mediterranean diet pattern, negative energy balance

Foods and beverages will be provided for participants for eight weeks. During the controlled feeding portion of the study the DGA Mediterranean diet pattern will be based on the Table A7-1 of the 2015 Dietary Guidelines for Americans which outlines daily nutritional goals for age-sex groups based on Dietary Reference Intakes (DRI) and dietary guidelines recommendations

Intervention Type: OTHER

TAD diet pattern, negative energy balance

Foods and beverages will be provided for participants for eight weeks. During the controlled feeding portion of the study the be based on evidence collected from What We Eat in America (WWEIA) data. Based on this data the participants will be provided a diet that reflects American dietary trends.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Body Mass Index (BMI) 23-39.9 kg/m2 or 32-50% body fat percentage
• Willingness to have blood drawn
• The criteria listed above and at least one of the following: Fasting glucose ≥100 mg/dL but <126 mg/dL or Fasting triglyceride ≥125 mg/dL or HDL-cholesterol ≤50 mg/dL or Blood Pressure (BP): Systolic BP ≥130 mmHg or Diastolic BP ≥85 mmHg or Hemoglobin A1C ≥ 5.7 and <6.5%

Exclusion Criteria

• Active participation in another research study
• Tested positive for COVID-19 within the past 10 days
• Been in close contact with a COVID-19 positive person within the past 14 days
• Blood Pressure (BP): Systolic BP ≥140 mmHg or Diastolic BP ≥90 mmHg
• LDL cholesterol ≥190 mg/dL
• Triglycerides ≥500 mg/dL
• Current use of smoking or chewing tobacco, e-cigarettes, cigars, vaping, cannabis or other use of nicotine containing products (within the past 6 months)
• Current use of dietary supplements and/or unwillingness to cease intake of dietary supplements
• Vegan or vegetarian lifestyle or any other dietary restrictions that would interfere with consuming the intervention foods and beverages (including dietary intolerances, allergies and sensitivities)
• Unwillingness to consume intervention foods and beverages
• Engage in more than moderate drinking (> 1 drink serving per day) or binge drinking (4 drinks within two hours).
• Unwillingness to cease alcohol intake as required for specific duration of the study
• Excessive intake of caffeine containing products (excessive defined as ≥ 400 mg/day)
• Unwillingness to refrain from caffeine intake on lab visit days.
• Intentional weight change of ≥5% of body weight within 6 months of entry into the study
• Diagnosis of disordered eating or eating disorder
• Recent diagnosis of any of the following or measurement on screening lab tests: Anemia (hemoglobin <11.7 g/dL) or abnormal liver or thyroid function (defined as liver enzymes that are >200% of upper limit (ALT upper limit is 43 U/L or Aspartate transaminase (AST) upper limit is 54 U/L) and thyroid function tests: Thyroxine (T4, free) <0.56 or >1.64 ng/dL; Thyroid-stimulating hormone (TSH) <0.35 or >5.6 μIU/mL).
• History of any of the following: Gastric bypass surgery, inflammatory bowel disease (IBD) or other GI conditions that would interfere with consuming the intervention foods, active cancer in the past three years excluding squamous or basal cell carcinomas of the skin that have been handled medically by local excision and other serious medical conditions
• Recent dental work or have conditions of the oral cavity that would interfere with consuming the intervention foods and beverages
• Taking any medication in the class of antipsychotics
• Long term use of antibiotics
• Taking any over the counter or prescribed medication for any of the following: Elevated lipids, elevated glucose, high blood pressure, weight loss or conditions that require corticosteroids (e.g. asthma, arthritis or eczema).
• Are pregnant, planning to become pregnant within the duration of the study or breastfeeding.

• Minimum Eligible Age: 19 Years
• Maximum Eligible Age: 64 Years
• Eligible Sex: FEMALE
• Accepts Healthy Volunteers: Yes

Sponsors

USDA, Western Human Nutrition Research Center

FED

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Kevin D Laugero, PhD

Role: PRINCIPAL_INVESTIGATOR

USDA, Western Human Nutrition Research Center

Locations

UC Davis, Western Human Nutrition Research Center

Davis, California, United States

Site Status: RECRUITING

Countries

United States

Central Contacts

Beverly Miller, BS, RDN

Role: CONTACT

bevmiller@ucdavis.edu

530-754-2541

Ellen Bonnel, PhD

Role: CONTACT

ellen.bonnel@usda.gov

530-752-4184

References

Krishnan S, Adams SH, Allen LH, Laugero KD, Newman JW, Stephensen CB, Burnett DJ, Witbracht M, Welch LC, Que ES, Keim NL. A randomized controlled-feeding trial based on the Dietary Guidelines for Americans on cardiometabolic health indexes. Am J Clin Nutr. 2018 Aug 1;108(2):266-278. doi: 10.1093/ajcn/nqy113.

Reference Type: BACKGROUND

PMID: 30101333 (View on PubMed)

Related Links

https://www.ars.usda.gov/pacific-west-area/davis-ca/whnrc/

WHNRC website

Other Identifiers

FL111

Identifier Type: -

Identifier Source: org_study_id