I was diagnosed with NASH about six months ago. I have done a few liver function tests and my ALT level is constantly over the normal range at around 80~100. What exactly is ALT? How important is it for my ALT to stay normal? What can I do to lower my ALT?
ALT (or GPT) is a liver enzyme. Under normal circumstances, this enzyme resides within liver cells. But if the liver is injured, it will causes the liver cells to break and spill the enzymes into the blood stream, raising the enzyme level in the blood.  The level of ALT, along with another less significant liver enzyme – AST, are measured in blood tests called liver function tests (LFTs) to detect liver damage.
The normal value of ALT varies among different laboratories, but the common results should be around 10–40 IU/L.  An elevated ALT level usually signals liver damage. Long term liver damage and inflammation (as suggested by constantly high ALT) increases the risk of other liver problems. This is because when liver cells are injured, they can repair themselves; but when this happens excessively and repeatedly over time, liver cells may eventually die and scar tissues may form. This is known as fibrosis, which may advance to cirrhosis.
Some scientists found that elevated levels of ALT at or over 25 IU/L of blood were predictive of cancer risk. This is less than the 40 IU/L commonly defined as the upper limit of normal levels.  Therefore NASH patients should target to maintain a low ALT level and do regular checkups.
Currently, there is no conventional medical therapy to lower ALT level in NASH patients as the cause is not yet known. NASH patients are generally advised to follow a healthy diet and do exercise; if you are overweight or obese, losing weight may also help to reduce fat in the liver which may reduce ALT level.  Apart from these standard recommendations, NASH patients should also focus on protecting their liver and preventing progression of the disease.
A clinical study on PubMed suggests that YHK, a natural alternative therapy, has an inhibitory effect on the development of NASH; it has been proven to effectively reduce inflammation in the liver and help liver cells recover. Research shows that over 80% of patients’ ALT normalized within 2 weeks of using YHK. 
In addition, it is also important for NASH patients to avoid the use of alcohol and unnecessary medications as these may hurt the liver further.
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- de Lima VM, de Oliveira CP, Sawada LY, Barbeiro HV, de Mello ES, Soriano FG, Alves VA, Caldwell SH, Carrilho FJ. (2007) “Yo jyo hen shi ko, a novel Chinese herbal, prevents nonalcoholic steatohepatitis in ob/ob mice fed a high fat or methionine-choline-deficient diet” Liver International Mar;27(2):227-34. PMID: 17311618
- * All research and clinical data should be used as reference purposes only, results may vary.