What is an LFT test?
A Liver Function Test (LFT) is a group of blood tests that measure different enzymes, proteins and substances produced by your liver. The liver performs over 500 functions including filtering toxins, producing proteins, and aiding digestion. LFT helps doctors detect liver damage, inflammation, fatty liver, hepatitis and other liver conditions early.
LFT Normal Range Chart
| Test | Normal Range | Unit |
|---|---|---|
| SGOT (AST) | 10 – 40 | U/L |
| SGPT (ALT) | 7 – 56 | U/L |
| Alkaline Phosphatase (ALP) | 44 – 147 | U/L |
| Total Bilirubin | 0.1 – 1.2 | mg/dL |
| Direct Bilirubin | 0.0 – 0.3 | mg/dL |
| Indirect Bilirubin | 0.1 – 1.0 | mg/dL |
| Total Protein | 6.0 – 8.3 | g/dL |
| Albumin | 3.5 – 5.0 | g/dL |
| Globulin | 2.0 – 3.5 | g/dL |
| GGT | 8 – 61 | U/L |
What does high SGPT (ALT) mean?
HIGH SGPT above 56 U/L
SGPT is the most specific marker of liver cell damage. High SGPT means liver cells are injured and leaking this enzyme into the blood. Common causes include fatty liver disease (NAFLD), alcohol use, hepatitis B or C, certain medications (paracetamol overuse, TB drugs), and obesity. Mildly high SGPT (up to 3x normal) is common with fatty liver.
What does high SGOT (AST) mean?
HIGH SGOT above 40 U/L
SGOT can be elevated due to liver damage but also from heart muscle damage, strenuous exercise, or muscle injury. When both SGOT and SGPT are high together, it strongly suggests liver disease. If SGOT is much higher than SGPT, alcohol-related liver disease or heart attack may be the cause.
What does high bilirubin mean?
HIGH Total Bilirubin above 1.2 mg/dL
High bilirubin causes jaundice — yellowing of skin and eyes. Causes include liver disease, bile duct blockage, or excessive breakdown of red blood cells (haemolysis). In newborns, high bilirubin (neonatal jaundice) is common and usually treated with phototherapy. High direct bilirubin suggests liver or bile duct problem; high indirect suggests red cell breakdown.
What does low albumin mean?
LOW Albumin below 3.5 g/dL
Low albumin indicates the liver is not making enough protein — this happens in chronic liver disease, cirrhosis, malnutrition or kidney disease (where albumin leaks into urine). Low albumin causes fluid to accumulate in legs and abdomen (oedema and ascites).
Fatty liver and LFT
In India, fatty liver (NAFLD) is extremely common due to high-carbohydrate diets, sedentary lifestyle and rising obesity. Fatty liver typically causes mildly raised SGPT (40–120 U/L) with normal bilirubin and albumin. It is reversible with diet changes and weight loss in early stages.