Moderately Carbohydrate-restricted Diet to Treat NAFLD in Adolescents

Summary

This will be a 6-month randomized clinical trial with two arms: moderately carbohydrate-restricted diet and a fat-restricted control diet. This 6-month study will have 2 phases: a 12-week controlled feeding phase and a 12-week "free living" phase. During the controlled feeding phase, all food will be provided to the families of the participants for the entirety of the 12 weeks. Participants (n=80) will have been diagnosed with NAFLD based on the presence of current evidence of active disease, which will be determined by the ongoing presence of hepatic steatosis estimated by diffusely echogenic liver via ultrasound suggestive of fatty liver and a serum alanine aminotransferase (ALT) level of 45 U/L or greater. All participants will be children and adolescents age 10-17 yrs.; will have an HbA1c \<7.0; and will be overweight or obese (BMI \>85th percentile). It is anticipated that most participants will be sedentary. The investigators will inquire as to routine physical activity at screening. All participants will be asked to maintain their usual level of physical activity throughout the study. Physical activity will be monitored via a smart watch provided to each participant at the beginning of the study, and participants will be queried weekly by the study dietitian regarding changes in physical activity. Participants who use oral contraceptives will be asked to maintain consistent use of these preparations throughout the study. Hormone use will be examined as a potential covariate in statistical analyses.

Conditions

• Non-Alcoholic Fatty Liver Disease
• Obesity

Interventions

OTHER

Moderately carbohydrate-restricted diet

For this study, the investigators will use the low glycemic, moderately carbohydrate-restricted diet that the investigators have previously shown is associated with depletion of hepatic lipid content, and improvement in insulin resistance in adolescents with NAFLD. This diet has a macronutrient composition of approximately 25% energy from carbohydrate, 20% energy from protein, and 55% energy from fat. No food group is excluded in this diet prescription; however, the diet emphasizes low-glycemic sources of carbohydrate, and includes mainly whole foods (vegetables, fruits, whole grains) with minimal highly processed grain products and added sugar. Protein foods will include meat, poultry, fish, eggs, and whey protein supplements if necessary. Fat-containing foods will include olive, coconut, and nut oils; butter; tree nuts and nut butters; cheese; cream; coconut milk; avocados; and the fat found in meat. A number of full-fat dairy products will be included.

OTHER

Fat-restricted diet

The fat-restricted, control diet will consist of approximately 60% carbohydrate, 20% protein, 20% fat. Participants will be given low-fat foods, whole-grain foods, fruits, and vegetables. The meal plans will minimize cholesterol, high-fat foods, high-cholesterol foods, processed starches, and added sugar, and will provide \<2300 mg/day sodium. Saturated fat will be limited to 10% of total fat intake, and all dairy products will be fat-free (or low fat).

Sponsors & Collaborators

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

  collaborator NIH

• University of Alabama at Birmingham

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

10 Years

Max Age

17 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2022-05-01

Primary Completion

2026-05-01

Completion

2026-05-01

Countries

• United States

Study Locations