Many factors can raise or lower ALT; interpretation hinges on pattern, co-tests, and history. Common causes of elevated ALT include viral hepatitis (A, B, C), nonalcoholic fatty liver disease, alcohol-associated liver disease, drug-induced liver injury from medications or supplements, autoimmune hepatitis, genetic liver disease, ischemic or hypoxic injury to the liver (shock, cardiac arrest), metabolic conditions (e.g., obesity, type 2 diabetes), and some other conditions, such as thyroid disease or celiac disease (mild elevations).
Low ALT is uncommon and seldom clinically significant, but may occur with severe liver failure, vitamin B6 deficiency, chronic illness, or frailty.
Because ALT is an enzyme, elevations reflect damage rather than liver function per se. ALT should always be contextualized with other markers and imaging if needed.
Some at-home or mail-in kits include ALT; however, lab interpretation is complex, so it’s essential to have a provider review the results.
No strict fasting requirement. But avoid heavy exercise or alcohol 24 hours beforehand for more stable results.
Most labs return ALT results within 24 to 48 hours.
Often during annual checkups (via the comprehensive metabolic panel). More frequent in those with liver disease or in people taking hepatotoxic medications.
Mild elevations are common; your provider may repeat the test, assess contributing factors, and monitor trends before doing a more extensive workup.
Yes, it’s typically covered when clinically indicated or when part of standard health panels. Insurance is not required with lab testing through Hers.
• AST (aspartate transaminase)
• ALP (alkaline phosphatase)
• Total bilirubin, direct bilirubin
• Gamma-glutamyl transferase (GGT)
• Liver function test (LFT)
• Comprehensive metabolic panel (CMP)
