Liver

ALT — Your Liver's Distress Signal

ALT is an enzyme found mainly in liver cells. When liver cells are damaged, ALT leaks into the blood, which makes it one of the more sensitive early markers of liver injury. It is usually measured together with AST, ALP and GGT, since the pattern between them says more than any single value.

Why Test ALT?

Your liver is remarkably forgiving, but it has its limits. Alcohol, extra weight, medications, viral exposure, even your daily diet -- they all leave a mark. An ALT test lets you see that mark before it becomes a problem. Track it over time and you get a real-time picture of how your lifestyle choices are landing. That's not just data. That's power.

What Do High ALT Levels Mean?

Elevated ALT usually points to liver trouble. Acute hepatitis -- from a virus, heavy drinking, toxins, certain medications, or an autoimmune flare-up -- can send ALT through the roof, sometimes taking months to settle back down. Fatty liver disease, obesity, and chronic liver cell damage are other common culprits. Your body might signal this with yellowing skin or eyes, stubborn fatigue, pain in the upper right abdomen, nausea, dark urine, loss of appetite, or persistent itching.

What Do Low ALT Levels Mean?

Low ALT? That's usually perfectly fine. In rare cases, very low levels might hint at a vitamin B6 deficiency or chronic alcohol use. Most people with low ALT feel completely normal, though some may notice mild fatigue or a dip in appetite.

Symptoms to Watch For

  • Jaundice (yellowing of skin and eyes)
  • Persistent fatigue or weakness
  • Upper right abdominal pain
  • Nausea and vomiting
  • Dark-coloured urine
  • Loss of appetite
  • Generalised itching

Who Should Get Tested?

  • Anyone curious about their liver health
  • Regular or heavy alcohol drinkers
  • People carrying extra weight or dealing with metabolic syndrome
  • Anyone on medications that can stress the liver
  • People with a family history of liver disease
  • Anyone who just wants a solid baseline

How to Prepare for Your Test

Skip the fatty foods and alcohol the day before. Bring valid ID on test day.

Order Your Blood Test

Test your ALT levels with an accredited Swedish laboratory. Results within days, reviewed by Wellth.

ALT (Alanine Aminotransferase) →

Frequently Asked Questions

What is the difference between ALT and AST?
Both are liver enzymes, but ALT is largely confined to the liver while AST is also present in heart and skeletal muscle. ALT is therefore the more liver-specific of the two, and the ratio between them helps indicate the cause of liver injury.
Can exercise affect my ALT results?
A tough workout can bump ALT up a little thanks to muscle breakdown. Nothing dramatic, but skip the heavy session the day before testing for the cleanest results.
How often should I test ALT?
If everything looks good, once a year as part of a general check-up is plenty. If levels are elevated, your doctor might want to retest every few weeks to months to keep an eye on things.
Can ALT levels return to normal?
Absolutely. Cut back on alcohol, lose some weight, treat an infection -- address the root cause and ALT often comes right back down.
NW

Reviewed by

Wellth Team

Wellth

Our content is written and reviewed by Wellth, and fact-checked against peer-reviewed research and current Swedish clinical guidelines.

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Medical Disclaimer

The information on this page is provided for informational purposes only and does not constitute professional medical advice, diagnosis, or treatment. Wellth provides health information and testing services but is not a substitute for clinical care. Always consult a qualified healthcare provider if you have questions about a medical condition. If you are experiencing severe or urgent symptoms, contact your doctor or call 1177 Vårdguiden. Blood test results should be interpreted by a qualified healthcare professional in the context of your complete medical history.