Triglycerides are fat molecules which are produced by digestion of food and released in the blood to be taken up by cells as needed for energy. High levels of triglycerides in your blood occur when calories ingested are more than calories expended. Alanine transaminase or ALT is a transaminase enzyme found in the liver. Because ALT enzymes are released by liver cells when the cells are damaged, elevated ALT levels may indicate liver damage. A combination of both elevated ALT and triglycerides may signal several health problems.
The combination of elevated liver enzymes and triglycerides may indicate that the patient has a "fatty liver." Fatty liver may be associated with the early stages of liver disease. If alcohol is ruled out as the cause of the elevated triglycerides in the liver, the patient may be diagnosed with nonalcoholic fatty liver disease or NAFLD. If a liver biopsy is performed and inflammation and liver damage is found in the liver cells, the diagnosis of nonalcoholic steatohepatitis or NASH may be made.
According to the National Digestive Diseases Information Clearinghouse or NDDIC, about 10 to 20 percent of Americans with elevated triglycerides and elevated liver enzymes have NAFLD and another 2 to 5 percent have NASH. Both diseases are becoming more common as a result of increasing obesity in adults over age 40.
Type 2 Diabetes
The American Diabetes Association published a study which suggested that elevated ALT levels and other factors including elevated triglycerides may be used to predict whether a patient will develop late-onset Type 2 diabetes.
Elevated liver enzymes, particularly ALT, have been shown to be a good indicator of fatty liver. Evidence is increasing to suggest that fatty liver can be related to the development of insulin resistance, which ultimately results in diabetes.
Fredrik H. Nystrom, M.D., of University Hospital of Linköping, Sweden reported that a "fast-food challenge" experimental diet for four weeks resulted in elevated ALT levels in young, healthy subjects after only one week, with a quadrupling of ALT levels after a month. Subjects ate a diet mostly consisting of fast-food hamburgers. Triglyceride levels increased who ate the fatty diet and gained weight. This study showed that short-term binge eating can result in elevated triglycerides and elevated ALT levels suggestive of liver damage.