Non-Alcoholic Fatty Liver Disease (NAFLD): Symptoms, Causes & Treatment

Non-alcoholic fatty liver disease (NAFLD) is a condition where fat accumulates in liver cells exceeding 5% of liver weight without significant alcohol consumption. It is the most common liver disease globally, particularly in developed and developing countries with high obesity rates. In the Middle East and Jordan, NAFLD is rising sharply due to increasing obesity and type 2 diabetes prevalence.

The disease has two main forms: simple steatosis (fat accumulation only) and non-alcoholic steatohepatitis (NASH), where inflammation and progressive fibrosis occur, potentially leading to liver failure. The disease typically results from insulin resistance, a condition where the body does not respond properly to insulin, increasing fat accumulation in the liver and other organs.

The primary cause of NAFLD is overweight and central obesity (abdominal fat distribution), though it can occur in lean individuals occasionally. The disease affects 25-30% of the global population, with NASH representing 3-5% of cases. Risk factors include metabolic syndrome, type 2 diabetes, dyslipidemia, and genetic predisposition.

In early stages of simple steatosis, no symptoms may be present, and the disease is often discovered incidentally during routine check-ups. As the disease progresses to NASH, various symptoms may emerge. Symptoms differ slightly between men and women and increase in severity with disease progression. Some patients may have no symptoms even with advanced cirrhosis.

• Fatigue and Tiredness: Persistent exhaustion even after rest, especially in late afternoon.
• Pain or Discomfort in Upper Right Abdomen: Mild pain or heaviness in the liver area.
• General Weakness: Muscle weakness and decreased physical energy.
• Jaundice (Yellowing of Skin and Eyes): In advanced stages when the liver cannot properly process bilirubin.
• Abdominal Bloating (Ascites): Fluid accumulation in the abdomen in advanced cirrhosis.
• Swelling in Legs and Feet: Fluid retention in lower extremities.
• Easy Bruising and Bleeding: Frequent nosebleeds or gum bleeding in advanced cases.
• Changes in Urine Color: Urine may become dark-colored.
• Loss of Appetite: Decreased appetite and nausea.
• Confusion and Tremors: Symptoms of hepatic encephalopathy in severe cases.

• Obesity and Insulin Resistance: Excess weight, especially abdominal obesity, increases secretion of substances causing insulin resistance and hepatic fat accumulation.
• Type 2 Diabetes: High blood sugar causes fat accumulation in the liver and increases liver inflammation.
• High Triglycerides and Cholesterol: Elevated blood lipids, particularly triglycerides, directly correlate with hepatic fat deposition.
• Diet Rich in Sugars and Saturated Fats: Consumption of simple sugars, saturated fats, and artificial sweeteners increases hepatic fat.
• Lack of Physical Activity: Sedentary lifestyle contributes to weight gain and disease progression.
• Genetic Factors: Certain gene mutations (e.g., PNPLA3) increase susceptibility to NAFLD development.
• Metabolic Disorders: Metabolic syndrome combines obesity, hypertension, diabetes, and elevated lipids.
• Medications and Chemicals: Some drugs (corticosteroids, older diabetes medications) may cause hepatic fat accumulation.

• Obesity: BMI greater than 30 significantly increases risk.
• Type 2 Diabetes: Associated with 60-70% of NAFLD cases.
• Metabolic Syndrome: Presence of three of five components (obesity, hypertension, diabetes, dyslipidemia).
• Age over 40 years: Prevalence increases with age, especially middle-aged adults.
• Male Gender: Men are more susceptible than premenopausal women.
• Family History: Family history of NAFLD or chronic liver disease.
• Elevated Triglycerides: Levels above 150 mg/dL increase risk.
• Low HDL Cholesterol: Low levels correlate with worse complications.
• Other Chronic Liver Diseases: Viral hepatitis or cirrhosis.
• Light Alcohol Consumers: Even small amounts may worsen the condition.

Diagnosis of NAFLD requires a combination of tests and examinations since symptoms may be unclear in early stages. The disease is often suspected when elevated liver enzymes are found in routine blood tests. The physician uses multiple diagnostic methods to confirm diagnosis and determine disease severity.

• Blood Tests (Liver Function Tests): Measuring liver enzymes (ALT and AST) - normal values less than 40 units/liter. ALT elevation greater than AST indicates NAFLD. Also measure bilirubin, albumin, and alkaline phosphatase.
• Metabolic Tests: Fasting glucose (should be less than 100 mg/dL), insulin, A1C (cumulative blood sugar index), and triglycerides (should be less than 150 mg/dL).
• Ultrasound: First-line and most common imaging to detect hepatic steatosis. Fat appears as increased echogenicity.
• Magnetic Resonance Imaging (MRI): More accurate than ultrasound in measuring hepatic fat content.
• Liver Elastography (Transient Elastography - FibroScan): Measures liver fibrosis degree using sound waves. Values less than 1.2 kPa indicate no fibrosis.
• Liver Biopsy: In rare cases when results are unclear, a small liver sample is taken for microscopic examination.
• Prediction Scoring Systems: Such as APRI and FIB-4 using blood results to estimate fibrosis degree.

Medications

• Pioglitazone: Improves insulin sensitivity and reduces inflammation. Used for NASH patients with mild fibrosis. Typical dose 15-30 mg daily.
• Vitamin E: Powerful antioxidant reducing inflammation. Used for non-diabetic patients at 800 IU daily. Avoided in diabetics due to increased cardiovascular risk.
• Resmetirom: Newly approved drug improving fat metabolism and hepatic inflammation. Given in escalating doses up to 100 mg daily.
• Additional Vitamins and Minerals: Vitamin D, selenium, and choline may help some patients but evidence is limited.
• Diabetes Medications (Metformin): Improves insulin sensitivity and may reduce liver inflammation. Dose 500-2000 mg daily.
• Lipid-Lowering Drugs (Statins): Such as atorvastatin and simvastatin to lower cholesterol and triglycerides.

Procedures and Surgery

• Weight Loss (Bariatric Surgery): In severe obesity (BMI over 40), gastric bypass or sleeve gastrectomy may be recommended. Rapidly reduces hepatic fat.
• Regular Monitoring: Blood tests every 3-6 months and annual imaging to ensure disease does not progress.
• Liver Transplantation: In end-stage cirrhosis and liver failure.

Lifestyle Changes (Foundation of Treatment)

• Weight Loss: Target 5-10% weight reduction improves hepatic fat; 30% reduction can reverse fibrosis. Gradual loss of 0.5-1 kg per week is optimal.
• Healthy Diet: Reduce simple sugars, soda, saturated fats, and red meat. Increase fiber (vegetables, fruits, whole grains). Mediterranean diet is ideal.
• Exercise: At least 150 minutes moderate-intensity aerobic activity weekly (brisk walking, swimming). Strength training twice weekly.
• Avoid Alcohol: Complete abstinence or minimal consumption (less than 1 drink daily for women, 2 for men).
• Diabetes Control: If diabetic, keep A1C below 7% and fasting glucose 80-130 mg/dL.
• Stress Management: Stress increases inflammation. Try yoga, meditation, and relaxation.
• Improve Sleep Quality: 7-9 hours daily sleep is essential for liver health.
• Avoid Harmful Herbal Supplements: Some herbs damage the liver. Consult your doctor before taking supplements.

• Non-Alcoholic Steatohepatitis (NASH): Progression from simple fat accumulation to actual liver inflammation causing cell damage and progressive fibrosis.
• Cirrhosis: Permanent liver scarring where healthy liver cells are replaced by scar tissue. This dramatically reduces liver function and is irreversible.
• Acute Liver Failure: Rapid loss of liver function that may occur suddenly, requiring hospitalization and intensive care.
• Hepatocellular Carcinoma (HCC): Primary liver cancer usually develops after years of cirrhosis. Cure rates are low if not detected early.
• Portal Hypertension: Elevated blood pressure in the portal vein carrying blood to the liver. Causes esophageal varices (enlarged veins) that may rupture and cause life-threatening bleeding.
• Ascites: Fluid accumulation in the abdomen causing severe bloating and risk of spontaneous bacterial peritonitis.
• Hepatic Encephalopathy: Accumulation of toxins (especially ammonia) the liver cannot clear, causing confusion, tremors, and in severe cases coma.
• Cardiovascular Disease: NAFLD patients have higher risk of coronary artery disease and stroke due to elevated lipids and chronic inflammation.

• Maintain Healthy Weight: Keep BMI between 18.5-24.9. If overweight, reduce gradually and consistently.
• Eat a Balanced Diet: Reduce added sugars, sugary drinks, and saturated fats. Choose whole grains, fresh vegetables, fruits, and lean proteins.
• Exercise Regularly: At least 30 minutes of moderate physical activity most days weekly. Helps with weight loss and improves insulin sensitivity.
• Control Blood Sugar and Lipids: If diabetic or have elevated lipids, monitor regularly with your doctor and follow prescribed treatment.
• Avoid or Limit Alcohol: Alcohol increases fat deposition and liver damage. Complete abstinence is preferable.
• Get Adequate Sleep: Sleep 7-9 hours daily. Poor sleep is linked to weight gain and insulin resistance.
• Manage Stress: Chronic stress increases inflammation. Practice relaxation techniques like meditation or yoga.
• Regular Health Screenings: If at risk (obesity, diabetes, high lipids), have annual liver function tests.
• Avoid Liver-Damaging Medications: Some drugs and supplements harm the liver. Consult your doctor before starting any new medication.
• Maintain Cardiovascular Health: Control blood pressure, blood sugar, and cholesterol to reduce NAFLD complications.