Elevated liver enzymes can be caused by many different factors, including a high-fat, high-protein diet; weight gain; changing exercise levels; alcohol consumption; disease, including liver disease; and other physiological and environmental causes. Its significance depends both on the general health of the individual and exactly how far out of range the enzyme levels are. It is not uncommon for a person to have higher than normal liver enzymes to occur for short periods of time, as the liver is the primary organ in the body that processes toxins and drugs, and digestive enzymes that break down protein come from the liver.
Liver enzymes most frequently looked at for health issues are alanine transaminase (ALT) and aspartate transaminase (AST). When the AST enzyme level is elevated the most, it can be indicative of alcoholic liver disease. When ALT is elevated the most, there is a more general look at possible causes and healthy liver function. If the elevated liver enzymes are marginally outside of standard ranges, they are considered something that warrants further medical testing and does not necessarily indicate that liver damage already exists.
The standard ranges in medicine for both ALT and AST levels are 7 to 56 units of serum per liter for ALT, and 5 to 40 units of serum per liter for AST, with serum being defined as the liquid component of blood. Blood tests for liver function and a repeat elevated liver enzymes test should only be interpreted with medical advice. These tests are just a snapshot in time of what the liver enzyme levels were when the blood sample was drawn. Someone with a ALT level of 250 is not necessarily in much worse shape than someone with an ALT of 50. In fact, a patient with viral hepatitis can temporarily have enzyme levels in the thousands of units and recover later with no liver damage.
One of the most common reasons for elevated liver enzymes is muscle strain. As someone performs tasks that require exertion that is not part of a routine, muscle tissue is broken down and reformed in the body. With this increased level of protein in the blood, enzyme levels rise to process it. Body builders and others who have fluctuating routines that involve muscle strain can regularly see ALT and AST levels 10 points or more above the standard average.
There are other common reasons for liver enzymes to become elevated. Some include taking medication such as aspirin, antidepressants, and pain killers. The onset of poor health such as pre-diabetes, fatty liver caused by obesity, and high levels of triglycerides in the blood which can indicate a high fat diet or overweight condition, also frequently are a cause for elevated liver enzymes. Herbal supplements, cancer, and gallstones as well are other common causes. The fact is that elevated liver enzymes can be traced to many sources, and a detailed look at an individual's current activities and health history is necessary to narrow down the cause and treat the condition properly.