The Lifestyle Education About Nutrition for Diabetes (Legend) Study

NCT ID: NCT05237128

Last Updated: 2025-11-10

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 182 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2022-03-22
• Study Completion Date: 2025-10-01

Brief Summary

This study is being completed to compare two dietary approaches for participants with type 2 diabetes. This research will test whether a very low-carbohydrate or a plate-method diet better improves outcomes for blood glucose control and body composition for patients with type 2 diabetes that follow one of these approaches for 12 months.

Participants that meet screening and eligibility will be randomized to one of the two diets. In addition to the diet, study specific visits and assessments will be performed at various timepoints.

Conditions

Type 2 Diabetes

Keywords

Very low-carbohydrate diet; Moderate-carbohydrate plate-method diet; Nutrition therapy

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: SINGLE

Study Groups

Very low-carbohydrate diet

Group Type: EXPERIMENTAL

Very low-carbohydrate diet

Intervention Type: BEHAVIORAL

Participants in this arm will be taught to manage their type 2 diabetes using a very low-carbohydrate diet, also called a ketogenic or "keto" diet. This diet involves eating non-starchy vegetables, leafy greens, cheese, meats, berries, nuts, and seeds and avoiding starchy foods like pasta, bread, rice, beans, many fruits, etc.

There will be a core phase and a maintenance phase of this study; the core phase will last for about 4 months and will involve weekly or every other week classes, home assignments, and brief check-in surveys. The maintenance phase will last for the remaining time, with classes and check-in surveys approximately once a month.

Moderate-carbohydrate plate-method diet

Group Type: EXPERIMENTAL

Moderate-carbohydrate plate-method diet

Intervention Type: BEHAVIORAL

Participants in this arm will be taught to manage their type 2 diabetes using a plate-method approach. This diet involves eating different categories of foods based on the proportions of a plate, balancing proteins, vegetables, fruits, starches, and fats.

There will be a core phase and a maintenance phase of this study; the core phase will last for about 4 months and will involve weekly or every other week classes, home assignments, and brief check-in surveys. The maintenance phase will last for the remaining time, with classes and check-in surveys approximately once a month.

Interventions

Very low-carbohydrate diet

Participants in this arm will be taught to manage their type 2 diabetes using a very low-carbohydrate diet, also called a ketogenic or "keto" diet. This diet involves eating non-starchy vegetables, leafy greens, cheese, meats, berries, nuts, and seeds and avoiding starchy foods like pasta, bread, rice, beans, many fruits, etc.

There will be a core phase and a maintenance phase of this study; the core phase will last for about 4 months and will involve weekly or every other week classes, home assignments, and brief check-in surveys. The maintenance phase will last for the remaining time, with classes and check-in surveys approximately once a month.

Intervention Type: BEHAVIORAL

Moderate-carbohydrate plate-method diet

Participants in this arm will be taught to manage their type 2 diabetes using a plate-method approach. This diet involves eating different categories of foods based on the proportions of a plate, balancing proteins, vegetables, fruits, starches, and fats.

There will be a core phase and a maintenance phase of this study; the core phase will last for about 4 months and will involve weekly or every other week classes, home assignments, and brief check-in surveys. The maintenance phase will last for the remaining time, with classes and check-in surveys approximately once a month.

Intervention Type: BEHAVIORAL

Eligibility Criteria

Inclusion Criteria

• diagnosis of type 2 diabetes, with current HbA1c > 6.5% and < 12% (self-reported and then measured at screening)
• ability to speak English (this is a group-based intervention)
• ability to engage in light physical activity
• willingness to be randomized to either type of diet

Exclusion Criteria

• unable to provide informed consent
• substance abuse, mental health, cognitive, or medical condition that would, in the opinion of the investigators, make it difficult for the individual to take part in the intervention, may alter key outcomes, or may require important diet modifications and includes conditions such as hypercalcemia or thyroid dysfunction
• pregnant or planning to become pregnant in the next 12 months, or currently breastfeeding (pregnancy and breastfeeding require modifications to the intervention's dietary approaches)
• current use of weight loss medications (this is likely to alter weight outcomes and may alter other measures)
• history of weight loss (bariatric) surgery or plans for bariatric surgery in the next year
• currently enrolled in a weight loss program or have unalterable plans to enroll in one of these programs in the next year
• vegan or vegetarian
• unwilling or unable to participate in study measurements and group classes
• current use of systemic steroids (self-reported in screening survey; oral or IV systemic steroids excluded. Injected steroids may be permitted depending on frequency and timing of injections with regard to lab assessments (minimum of 2 weeks between injection and blood tests))
• weight above 400 pounds (weight limit for dual-energy X-ray absorptiometry (DEXA) scans)
• history of multiple or recent (within the last four years) kidney stones
• currently following a very low-carbohydrate diet
• unwilling to stop an SGLT2 inhibitor medication if the participant were to be randomized to the very low-carbohydrate diet

• Minimum Eligible Age: 21 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

NIH

Sponsor Role: collaborator

University of Michigan

OTHER

Sponsor Role: lead

Responsible Party

Laura Saslow

Assistant Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Laura Saslow, PhD

Role: PRINCIPAL_INVESTIGATOR

University of Michigan

Locations

The University of California San Francisco (UCSF)

San Francisco, California, United States

University of MIchigan

Ann Arbor, Michigan, United States

Countries

United States

References

Saslow LR, Eslamian A, Moran P, Hartogensis W, Mason AE, Kim S, Bauer DC, Griauzde DH, Goldman V, Liu V, Stephens P, Raymond K, Yeung G, Leung C, Hecht FM. Protocol for a randomized controlled trial comparing a very low-carbohydrate diet or moderate-carbohydrate plate-method diet for type 2 diabetes: the LEGEND (Lifestyle Education about Nutrition for Diabetes) trial. Trials. 2023 Jul 20;24(1):463. doi: 10.1186/s13063-023-07512-9.

Reference Type: DERIVED

PMID: 37475033 (View on PubMed)

Provided Documents

Document Type: Informed Consent Form

View Document

Other Identifiers

R01DK126898-01A1

Identifier Type: NIH

Identifier Source: secondary_id

View Link

HUM00202808

Identifier Type: -

Identifier Source: org_study_id