If you are not overweight, it is still most likely caused by poor diet (high fat and
high sugar diets especially). Insulin resistance and
diabetes can also make you prone to fatty liver and nash
If fatty liver progresses it is called nash (Nonalcoholic Steatohepatitis), this means you that you not only have a greasy fatty liver, but you have larger deposits of fat in your liver and this can lead to serious liver disease and cirrhosis if you do not take care of yourself.