AST (Aspartate Aminotransferase)

What AST Measures

AST is an enzyme, a protein that speeds up chemical reactions inside cells. It's concentrated in the liver, but it also lives in skeletal muscle, heart muscle, kidney, brain, and red and white blood cells.^[1] When cells in any of those tissues are damaged, they release AST into the bloodstream, and that's what the blood test measures.^[2] So an AST level reflects cell damage somewhere in the body rather than pointing at one organ. That's the main difference from ALT, a related enzyme that sits mostly in the liver and is treated as a more liver-specific marker.^[1]

How It's Measured

AST comes from a standard venous blood draw and is reported in units per liter (U/L). It's rarely ordered on its own. It usually arrives as one line on a liver panel or a comprehensive metabolic panel, next to ALT, alkaline phosphatase, and bilirubin.^[2],[4] Your lab report may label it SGOT (serum glutamic-oxaloacetic transaminase), an older name for the same test that some labs still use.^[2] Labs set and report their own reference interval with each result.

Why People Track AST

AST shows up on almost any routine blood panel, so anyone who gets regular bloodwork already has a running series of AST values.

Context matters for this one because AST moves with more than the liver. In a study of healthy men, a single session of intense weightlifting raised AST and ALT significantly, and the levels stayed elevated for at least seven days.^[3] Muscle is full of AST, so hard training breaks down muscle cells and releases the enzyme into the blood.^[1],[3] A dated record of when a draw fell relative to your workouts keeps that context attached to the number.

How Go Go Gaia Tracks AST

Go Go Gaia doesn't draw blood or run lab work. You upload an AST result from bloodwork you've already had done, and the app stores it as a dated data point labeled AST (SGOT) in U/L. Each new upload extends the same chart, so your AST history sits on one timeline next to your logged workouts, cycle days, and other lab values.

What the Research Shows

AST's wide tissue distribution is standard textbook physiology: it's present in skeletal muscle, heart muscle, kidney, brain, and both red and white blood cells, which is why it's described as a less liver-specific marker than ALT.^[1]

Exercise alone can move it. In healthy men with no liver disease, intense weightlifting significantly raised AST, ALT, creatine kinase, and myoglobin, and the authors flagged recent strenuous exercise as a cause of enzyme elevations in otherwise healthy people.^[3]

Related Terms

Frequently Asked Questions

Educational information based on published sources. Not medical advice. For personal concerns, please consult your doctor.

Does Go Go Gaia run AST blood tests?

No. Go Go Gaia doesn't draw blood or run labs. You get an AST result from a blood draw ordered through a clinician or lab service, then upload it to your Go Go Gaia account so it's stored and charted alongside your other tracked data.

Is SGOT the same thing as AST?

Yes. SGOT (serum glutamic-oxaloacetic transaminase) is an older name for the same test, and some labs still print it that way. Go Go Gaia displays the metric as AST (SGOT) so results labeled either way land in the same place.

Why is AST on a liver panel if it's found in other tissues too?

The liver holds a lot of AST, so liver and comprehensive metabolic panels include it as one of their standard enzymes. But because AST also lives in heart, skeletal muscle, kidney, and red blood cells, a blood level reflects more of the body than the liver alone. That's a question of tissue distribution, and it's why AST is usually measured alongside ALT, an enzyme that's more specific to the liver.