While I was trying to navigate my way around holiday foods that might not be liver-friendly, the American College of Gastroenterology (ACG) published new normal ranges for liver enzyme tests. Ask someone with hepatitis C what their ALT levels are, they will likely know the number. But for those who are learning the liver lingo, ALT is short for alanine aminotransferase. Hep has a good description of this, along with other liver-related labs on the Hepatitis C Lab Tests page.

Before I talk about these new normals, or reference ranges as they say in the business, it’s important to note that references ranges vary depending on the lab. One lab might have ALT references ranges from as 5 to 35; another might use 7 to 56. I’ve seen highs up to 65. So when comparing liver enzyme tests, it’s important to compare apples to apples. Just becuase these ranges have been set, your lab may not follow them yet.  

Back to the new guidelines. For many years, the normal ranges were the same for women and men. Savvy doctors knew that ALT ranges were too high for women, and that a woman with a result of 30 IU/L may be exhibiting signs of a complaining liver. However, many doctors, especially if they weren’t liver specialists, would have said that was a normal result.  In general, the normal ranges for men were also too low.

The experts at ACG analyzed liver-related mortality rates from the U.S., Europe, and Asia and decided to set new reference ranges for ALTs. The healthy range for females is 19-25 IU/L; males is 29-33 IU/L. Results higher than this need further medical evaluation. Click here to learn more about the specifics of the new guidelines, along with an explanation of what further assessments are recommended for people with elevated ALTs.


So when you get your next liver panel, look to see what the reference ranges are. If the lab isn’t using the newest ranges, point them towards the new normals.