Alternate Day Fasting, Exercise, and NAFLD

NCT ID: NCT04004403

Last Updated: 2025-09-25

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 80 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2019-09-01
• Study Completion Date: 2024-05-01

Brief Summary

Approximately 65% of obese individuals have non-alcoholic fatty liver disease (NAFLD), and this condition is strongly related to the development of insulin resistance and diabetes. Innovative lifestyle strategies to treat NAFLD are critically needed. The proposed research will demonstrate that alternate day fasting (ADF) combined with exercise is an effective non-pharmacological therapy to treat NAFLD.

Detailed Description

Nonalcoholic fatty liver disease (NAFLD) is characterized by an accumulation of fat in the liver (not resulting from excessive alcohol consumption). Approximately 65% of obese individuals have NAFLD, and this condition is strongly related to the development of insulin resistance and type 2 diabetes. While certain pharmacological agents have been shown to reduce liver fat (i.e. thiazolidinediones), there is mounting concern regarding the safety and weight-gaining effects of these compounds. In light of this, recent research has focused on non-pharmacological lifestyle therapies to reduce hepatic steatosis, such as daily calorie restriction combined with aerobic exercise. Evidence from clinical trials suggest that this combination is an effective lifestyle therapy improve liver fat content and hepatic insulin sensitivity.

More recently, it's been shown that intermittent fasting may produce even greater improvements in hepatic steatosis and hepatic insulin sensitivity, when compared to conventional calorie restriction. For instance, intrahepatic lipid accumulation was lower and insulin sensitivity was higher in mice fasted every other day, when compared to mice who were energy restricted every day. Moreover, data from human trials show that adults with obesity experience greater decreases in insulin and insulin resistance with intermittent fasting versus daily restriction. These findings suggest that intermittent fasting may be a more effective diet therapy to reduce hepatic steatosis and improve insulin sensitivity, when compared to daily calorie restriction. Although these findings are very promising, these data still require confirmation by a randomized controlled clinical trial.

Conditions

Non-Alcoholic Fatty Liver Disease; Obesity

Study Design

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

Study Groups

Alternate day fasting

These participants will consume 600 kcal on the "fast day" and eat ad libitum at home on alternating "feed days".

Group Type: EXPERIMENTAL

Alternate day fasting

Intervention Type: OTHER

The diet involves consuming 600 kcal on the "fast day" and eat ad libitum at home on alternating "feed days".

Exercise

These participants will participate in a supervised aerobic exercise program 5 times per week, 40-60 min per session, 60-85% HRmax.

Group Type: EXPERIMENTAL

Exercise

Intervention Type: OTHER

The exercise intervention involves supervised aerobic exercise program 5 times per week, 40-60 min per session, 60-85% HRmax.

Combination alternate day fasting plus exercise

These participants will consume 600 kcal on the "fast day" and eat ad libitum at home on alternating "feed days". They will also participate in a supervised aerobic exercise program 5 times per week, 40-60 min per session, 60-85% HRmax.

Group Type: EXPERIMENTAL

Alternate day fasting

Intervention Type: OTHER

The diet involves consuming 600 kcal on the "fast day" and eat ad libitum at home on alternating "feed days".

Exercise

Intervention Type: OTHER

The exercise intervention involves supervised aerobic exercise program 5 times per week, 40-60 min per session, 60-85% HRmax.

Control

Controls will be instructed to maintain their weight throughout the trial, and not to change eating or physical activity habits.

Group Type: NO_INTERVENTION

No interventions assigned to this group

Interventions

Alternate day fasting

The diet involves consuming 600 kcal on the "fast day" and eat ad libitum at home on alternating "feed days".

Intervention Type: OTHER

Exercise

The exercise intervention involves supervised aerobic exercise program 5 times per week, 40-60 min per session, 60-85% HRmax.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Age between 18 to 65 years old
• BMI between 30.0 and 59.9 kg/m2
• NAFLD (hepatic steatosis ≥ 5% confirmed by MRI-PDFF)
• Sedentary (<20 min, 2x/week of light activity at 3-4 metabolic equivalents (METs) for 3 mo prior to study)

Exclusion Criteria

• Have chronic liver disease other than NAFLD (hepatitis B or C, primary biliary cirrhosis, sclerosing cholangitis, autoimmune hepatitis, hemochromatosis, Wilson's disease, α1-antitrypsin deficiency)
• Consume excessive amounts of alcohol women: 70 g of ethanol (5 alcoholic drinks per week) and men 140 g of ethanol (10 drinks per week) in the past 6 months)
• Have a history of known cardiovascular, pulmonary or renal disease
• Diagnosed T1DM or T2DM
• Are not weight stable for 3 months prior to the beginning of study (weight gain or loss > 4 kg)
• Are claustrophobic or have implanted metallic/electrical devices (e.g. cardiac pacemaker, neuro-stimulator)
• Are taking drugs that induce steatosis (e.g. corticosteroids, estrogens, methotrexate, Ca channel blockers)
• Are taking drugs that benefit NAFLD (e.g. betaine, pioglitazone, rosiglitazone, metformin, or gemifibrozil)
• Are taking drugs that influence study outcomes (weight loss medications)
• Are perimenopausal or have an irregular menstrual cycle (menses that does not appear every 27-32 days)
• Are pregnant, or trying to become pregnant
• Are smokers

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

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

NIH

Sponsor Role: collaborator

University of Illinois at Chicago

OTHER

Sponsor Role: lead

Responsible Party

Krista Varady

Professor of Nutrition

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Krista Varady, PhD

Role: PRINCIPAL_INVESTIGATOR

University of Illinois Chicago

Locations

University of Illinois Chicago

Chicago, Illinois, United States

Countries

United States

Provided Documents

Document Type: Study Protocol and Statistical Analysis Plan

View Document

Other Identifiers

R01DK119783

Identifier Type: NIH

Identifier Source: secondary_id

View Link

2019-0300

Identifier Type: -

Identifier Source: org_study_id