Alanine aminotransferase (ALT) is an enzyme that appears mostly in the liver. Having high levels of ALT may be a sign of liver disease. While ALT can also be found in the kidneys, heart, and muscle ...

This article was reviewed by Felix Gussone, MD. In this guide, we’ll break down what most biomarker lab tests measure, how to prepare for them, and what to do once you receive your results. Not ...

This article was reviewed by Felix Gussone, MD. Preparing properly for lab tests helps ensure your results are accurate and reliable. Some tests — like fasting cholesterol or fasting glucose — require ...