What is fatty liver disease?
Non-alcoholic fatty liver disease (NAFLD) — now renamed metabolic dysfunction-associated steatotic liver disease (MASLD) — is characterised by excess fat accumulation in liver cells (hepatocytes) in people who drink little or no alcohol. It ranges from simple steatosis (fat only, benign) to NASH (non-alcoholic steatohepatitis — fat plus inflammation) to fibrosis and cirrhosis. It is strongly linked to obesity, type 2 diabetes, insulin resistance and metabolic syndrome.
Fatty liver grading
| Grade | Fat in liver cells | Blood tests | Outlook |
|---|---|---|---|
| Grade 1 (Mild) | 5–33% | ALT mildly elevated or normal | Fully reversible with lifestyle |
| Grade 2 (Moderate) | 34–66% | ALT moderately elevated | Reversible; needs intervention |
| Grade 3 (Severe) | >66% | ALT elevated; may see low albumin | Risk of NASH and fibrosis |
| NASH | Steatosis + inflammation | ALT/AST elevated, possibly INR raised | Progress to cirrhosis if untreated |
Blood test results in fatty liver
| Test | Typical finding in fatty liver |
|---|---|
| ALT (SGPT) | Mildly-moderately elevated (1–4x normal) |
| AST (SGOT) | Elevated; AST:ALT ratio <1 (unlike alcoholic liver disease) |
| GGT | Often elevated |
| Fasting glucose / HbA1c | Raised — insulin resistance is often present |
| Triglycerides | Often elevated |
| Ferritin | Often mildly elevated (inflammation marker) |
| Albumin / INR | Normal in early stages; abnormal in cirrhosis |
What causes fatty liver?
- Obesity — especially central/abdominal fat
- Type 2 diabetes and insulin resistance
- High-carbohydrate and high-fructose diet (soft drinks, refined carbs)
- High triglycerides (hypertriglyceridaemia)
- Rapid weight loss or starvation (mobilises fat to the liver)
- Certain medications: corticosteroids, amiodarone, tamoxifen, methotrexate
- Hypothyroidism (slows fat metabolism)
How to reverse fatty liver
Weight loss
Losing 7–10% of body weight reduces liver fat significantly. Losing 10% or more can reverse NASH and even early fibrosis. This is the single most effective intervention.
Diet changes
Reduce refined carbohydrates (white bread, pasta, sugar, soft drinks). Increase vegetables, wholegrains, legumes, lean protein and olive oil. The Mediterranean diet is the most evidence-based diet for fatty liver.
Exercise
Both aerobic exercise (brisk walking, cycling) and resistance training reduce liver fat independently of weight loss. Aim for 150+ minutes of moderate activity per week.
Alcohol
Even modest alcohol intake worsens fatty liver. Complete abstinence is ideal during recovery.
Questions to ask your doctor
- Do I need a liver ultrasound to grade my fatty liver?
- Should I have a FibroScan (liver elastography) to assess fibrosis?
- Is my blood sugar or insulin resistance contributing?
- What diet changes will have the fastest impact?
- When should I retest my liver enzymes?