Diet Guidelines: 3 diets (DG3d)

Interested in improving your diet and reducing your risk of developing type 2 diabetes…all while eating great?! Then DG3D at the University of South Carolina (UofSC) may be for you. We’re looking for African American adults between the ages of 18 and 65 who can participate in a 1 year, exciting healthy eating and lifestyle study that will conclude with assessments of your diet, weight, and health behaviors. As part of this study, you will be randomized to follow one of three healthy diets that are part of the US Dietary Guidelines: a Healthy US diet, a Mediterranean diet, or a Vegetarian diet. You will learn how to cook healthy and delicious recipes here at USC so that you can enjoy the health benefits from nutritious meals that taste great.

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Thank you for your interest in the DG3D Study! Enrollment is now open for our 2nd Cohort that will begin in 2023. Slots are limited and enrollment in the study will be done on a first come, first served basis.

Please CLICK HERE to submit your online application for enrollment. Upon completion of your application, we will review your application and will contact you with next steps. Please allow up to 7 business days for a member of our team to review and contact you regarding your application.


Participants must meet the following criteria in order to participate:

  • Self-identify as African American
  • Be between the ages of 18-65 years
  • Have a Body Mass Index between 25- 49.9 kg/m2
  • Live in the Columbia, SC area
  • Not currently pregnant
  • Be free of type 2 diabetes
  • Not currently taking prescription medicine to control type 2 diabetes
  • Be able to attend all monitoring visits
  • Be willing to be randomized to either of the three diets
  • Not currently following a vegan, vegetarian, or Mediterranean diet

Study Benefits

See what other participants have said about participating in our nutrition studies!

Participating in our studies is fun and can be life changing for your health. See what our former participants have said about our studies and working with Dr. Brie and her team.

Community Advisory Board

Keith Alexander

Local Businessperson and
Former Educator


Kevin “Big Redd” Felder

Radio executive and host of nationally syndicated Christian hip-hop program The Big Redd Radio Show


Ashley Page Bookhart

SNAP-Ed Program Coordinator
USC Department of Health Promotion, Education and Behavior


Dr. Martin Luther Quick

Author of e-Vangelism: Creating and Implementing a Social Media Ministry for Outreach

Lead pastor at Cumberland United Methodist Church


Beverly Wilson

Co-Founder and Executive Director


Frequently Asked Questions (FAQ)

What is the purpose of this study?

Improving your diet can have a significant impact on your health, but it’s not known which diet can best address health needs. Many nutrition studies in the past have not included African American participants. For this study, we are only recruiting African American adults. We hope to learn from you about which diets work best to help prevent chronic disease and improve body weight.

What’s the study about?

The Diet Guidelines: 3 Diets (DG3D) study is comparing three different diets, as defined by the US Dietary Guidelines and how they impact type 2 diabetes risk factors among African American adult (such as body weight, blood pressure, and hemoglobin A1c). The intervention will last for 1 year and participants will be randomly assigned to follow a Healthy US diet, Vegetarian diet, or Mediterranean diet and receive cooking classes, recipes, and guidance for following their assigned diet based on culturally-tailored curriculum.

What will I get by participating?

Free cooking classes, recipes, a support system, and lab results at the end of the study.  If you complete the study, you’ll receive $100.00.

How could participating help me?

You may lose weight and reduce your risk of developing type 2 diabetes by being a part of this study. You will receive cooking classes and learn how to prepare healthy meals.

Who can participate in this program?

You must:

  • Be between the ages of 18 – 65 years
  • Self-identify as African American
  • Have a body mass index (BMI) between 25–49.9 kg/m2 (be overweight or obese)
  • Be available to attend all study meetings over a 1 year period.
  • Be willing to be randomized to either of the 3 diet groups (this means you won’t have a choice in which diet you are assigned to)

Is the study only for African Americans?

Yes. You must self-identify as an African American in order to qualify and participate. 

How can I calculate my BMI to know if I qualify for the study?

You can calculate your BMI online with this online calculator:

Can my spouse participate as well?

Only one person per household can participate in the study as a research participant, but you are free to share all your class materials with friends and family.

What commitment is required of me?

This study will last for 1 year and will therefore require a short-term commitment. You will be required to regularly come to the University of South Carolina’s Arnold School of Public Health for classes, lab visits, and to complete a variety of surveys. You will be required to attend classes once a week for 6 months and then every other week for the remaining 6 months. The classes are structured to be about an hour and fifteen minutes in the evening at the University of South Carolina’s Arnold School of Public Health.

What will I have to do in the program?

You will attend group classes to learn more about your diet and receive the support you need to adopt healthier eating habits. The classes will include cooking skills, recipe ideas, and guidance for following your assigned diet.

You will have lab visits that involve height and weight measurements, blood pressure, and a non-fasting blood draw via finger stick. The lab visits will be at the following time points: baseline and 6 months and 1 year.

You will also be completing several questionnaires at each time point: baseline, 6 months and 1 year. You will complete the questionnaires at your classes or at your house and be required to complete online dietary recalls at home. The questionnaires will assess demographic information, psychosocial variables (such as stress), and dietary acceptance. The dietary recalls are online surveys that ask you to recall all the meals and beverages you had in the previous 24-hours. You will be directed to an online database that allows you to enter in the foods and drinks you had for the day.

Can I pick what diet group I belong in or what diet I get to eat?

No. Because this study is using random assignment, participants will be randomly assigned to each diet group. You must be willing to be assigned to either of the 3 diets.

Where are the study meetings located?

Classes will be held at the Discovery I Building at the Arnold School of Public Health on the first floor. The address is 915 Greene Street, Columbia SC 29201. It is right across the street from the Colonial Life Arena.

Can I bring my spouse or a friend to class?

Due to COVID-19 and social distancing protocol, we will limit class attendance to only participants.

What happens if I can’t attend a class?

Please let one of our study coordinators know that you will miss a class and you will be provided with instructions to complete a make-up class. 

What do I do during lab assessments?

You will have your blood drawn (non-fasting) via a finger stick by a phlebotomist at USC’s Prevention Research Center. You will have your body weight, height, blood pressure, waist circumference, and hip circumference measured.

What if I am interested in participating in the study?

Thank you for your interest in the DG3D Study. Recruitment is now open for our 2nd Cohort. Please CLICK HERE to complete an enrollment application to indicate your interest in participating in this study. Upon receipt of your application, we will be in touch within 5-7 business days to confirm your eligibility.

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