The Optimal DX Research Blog

Lifestyle changes improve NAFLD

Written by ODX Research | Apr 16, 2025 7:15:00 AM

Non-alcoholic fatty liver disease (NAFLD), characteristically similar to metabolic dysfunction-associated fatty liver disease, has a worldwide prevalence of 25%. It is rapidly becoming the number one cause of cirrhosis and liver cancer.

Weight loss is first-line therapy in NAFLD treatment. A 7-10% reduction in weight improved:

  • Fibrosis
  • Hepatocyte ballooning
  • Inflammation
  • Steatosis

Weight reduction associated with a calorie deficit of 750-1000 Calories/day or a 30% calorie reduction from current intake can improve:

  • ALT, AST, GGT
  • Fasting glucose
  • Free fatty acids
  • Hepatic steatosis
  • Insulin sensitivity

Exercise interventions, based on at least 150 minutes of moderate exercise, including aerobic and resistance training weekly, can significantly improve:

  • Glucose homeostasis
  • Insulin sensitivity
  • Intrahepatic triglycerides
  • Liver enzymes

For optimal outcomes, weight loss goals should be combined with daily exercise and a healthy Mediterranean-style diet. A systemic review and meta-analysis showed that combining exercise with diet interventions improved ALT, AST, GGT, and HOMA-IR parameters better than either intervention alone. The analysis included 3,280 subjects 33-61 years of age with varying degrees of NAFLD.

Trials evaluating the combination of diet and exercise in NAFLD parameters

Author, year

Type of intervention

Supervision

Duration

Intervention group protocol

Control group protocol

Outcomes

Changes post intervention

 

Al-Jiffri, 2013

Exercise + Diet

No

13 weeks

EX: 5-minute warm-up phase on the treadmill. Endurance training session for 30 minutes. 5-minute recovery

No intervention

liver enzymes, HOMA-IR, insulin

BMI*☨

 

ALP, ALT, AST,

 

GGT*☨

 

HOMA-IR*☨

 

D: low calorie diet (1200 kcal): 15% as protein, 30 to 35% as fat and 50 to 55% as CHO

 

Arab, 2017

Exercise + Diet

No

9 weeks

Eight lifestyle sessions about healthy eating and regular physical activity for 5 days/week

Usual care

Weight, BMI, other body composition measures

Weight*

 

BMI*☨

 

Abdominal circumference*

 

Lean body mass*

 

Percent of body fat*

 

Cheng, 2017

Exercise + Diet

Yes

37 weeks

AER: Progressive aerobic training program. 5 min warm-up, 30–60 minutes session, 5 minutes cool-down. 65 to 70% of VO2max.

No intervention

HFC, HbA1c, insulin sensitivity, body composition, total cholesterol, liver enzymes

HFC*☨

 

Weight (only in AED group)

 

FM☨

 

fat% ☨

 

HbA1c (only AED group)

 

D: 30–40%of the total daily energy intake. 37–40% CHO, 9–13 gr as fiber, 35–37% fat, 25–27% protein. Maintain personal physical activities

 

AED: AER + D protocols.

 

Dong, 2016

Exercise + Diet

Yes

104 weeks

D: Negative calorie balance of (25–30 c/kg/d) for overweight and obese. Neutral calorie balance (30–35 c/kg/d) for normal BMI. 20–30% fat, 15–20% protein, 50–60% CHO

Lifestyle counseling

Weight, liver enzymes, IHL content, lipid profile, fasting plasma glucose

Weight*

 

—BMI

 

NAFLD fibrosis score*

 

ALT*, —AST, —GGT

 

TC*, —TG,

 

HDL*, LDL*

 

EX: Favorite aerobic exercise or activity, moderate intensity (60–80% of heart rate) to vigorous (>80%).

 

Eckard, 2013

Exercise + Diet

Yes

26 weeks

D: Nutrition prescription based on individualized calorie needs subtracting 500 kcal/day and macronutrient distribution

Standard care

Liver biopsy (NAS), body composition, lipid profile, liver enzymes, HbA1c, glucose, insulin

—Weight

 

—Fat mass %

 

NAS*

 

ALT, AST*

 

—Fasting glucose

 

—Insulin

 

EX: Education about exercise based on ACSM’s recommendations.

 

Katsagoni, 2018

Exercise + Diet

Self-monitoring

26 weeks

Energy restriction regimen. 45% CHO, 20% protein, 35% lipids. 1500 kcal women, 1800 kcal men.

Energy restriction regimen. 45% CHO, 20% protein, 35% lipids. 1500 kcal women, 1800 kcal men + general written dietary guidelines for a healthy lifestyle.

Weight, BMI, WC, ALT, GGT, Liver stiffness, NAFLD fibrosis score, glucose, insulin, HOMA-IR, lipid profile

Weight*☨

 

BMI*☨

 

Liver stiffness*☨

 

ALT only in MLG group*

 

MDG: Seven 60-min small group sessions about improving diet quality and energy restriction held every 2 weeks for the first 2 months and every month for the next 4 months.

 

MLG: MDG + enhancing activity through a moderate–vigorous intensity physical activity program as well as for optimal sleep duration and mid-day rest.

 

—HOMA-IR

 

LDL only MDG group*

 

—blood pressure

 

Adherence to intervention*

 

Promrat, 2010

Exercise + Diet

No

48 weeks

Weight loss intervention based on different strategies used successfully in other trials (diet, exercise, and behavior changes)

Small group sessions providing basic education about NASH, healthy eating, physical activity, and weight control.

Weight, BMI, ALT, AST, TC, LDL, HDL, TG, glucose, HbA1c, insulin, HOMA

Weight*☨

 

WC*☨

 

NAS*☨

 

ALT*☨

 

— HOMA, insulin, HbA1c

 

Sun, 2012

Exercise + Diet

No

12 weeks

Diet: 30% fat, 15% proteins and 55% carbohydrates, including 5% sugar. Energy intake: 25–30 kcal/kg. EX: walking, jogging, stair climbing and physical exercise, 23 (METs)•h/week (physical activity) + 4 METs•h/week (exercise).

Basic education about NAFLD and principles of healthy eating, physical activity, and weight control

Weight, BMI, WC, ALT, AST, GGT, TC, TG, fasting glucose, HOMA-IR, visceral fat area

Weight*☨

 

BMI *☨

 

WC*☨

 

ALT*☨

 

AST, GGT*

 

— TG, TC, fasting glucose

 

HOMA-IR*

 

VFA*

 

* Statistically significant within group,

☨ statistically significant compared to control group,

↓ decreased, ↑ increased, — no change. Abbreviations: ACSM: American college of sports medicine, AED: aerobic exercise + diet, AER: aerobic, ALP: alkaline phosphatase, ALT: alanine transferase, AST: aspartate transferase, BMI: body mass index, CHO: carbohydrates, D: diet, EX: exercise, FM: fat mass, GGT: gamma glutamyl transferase, HbA1c: glycated hemoglobin, HDL: high density lipoprotein, HFC: hepatic fat content, MDG: Mediterranean diet group, MET: metabolic equivalent of task MLG: Mediterranean lifestyle group, TC: total cholesterol, TG: triglycerides, VFA: visceral fat area,VO2 max: maximum oxygen consumption, WC: waist circumference.

Optimal Takeaways

  • Healthy weight loss can significantly improve NAFLD
  • Lifestyle changes should include:
    • A healthy Mediterranean-style diet
    • At least 150 minutes weekly of moderate exercise, including aerobic and resistance training.
    • Maintaining a healthy weight and body composition
  • Combining diet, weight maintenance, and exercise yields the most favorable results.

Reference

Fernandez, Tiziana et al. “Lifestyle changes in patients with non-alcoholic fatty liver disease: A systematic review and meta-analysis.” PloS one vol. 17,2 e0263931. 17 Feb. 2022, doi:10.1371/journal.pone.0263931 https://creativecommons.org/licenses/by/4.0/