This is the most important and liver-specific enzyme in your health panel. The SGPT (ALT) test measures an enzyme found almost exclusively in your liver. Because it's so liver-specific, an elevated level is a clear, early, and highly reliable sign of liver inflammation or damage (e.g., from fatty liver, hepatitis, or medications). This test is the gold standard for monitoring liver health. A simple blood draw provides this critical, actionable data, giving you the power to protect your liver.