A fatty liver is the result of the excess fat in liver cells. Fatty tissue slowly builds up in the liver when a person’s diet exceeds the amount of fat his or her body can handle. A person has a fatty liver when fat makes up at least 5% of the liver . Simple fatty liver can be a completely benign condition and usually does not lead to liver damage. However, once there is a buildup of simple fat, the liver becomes vulnerable to further injury, which may result in inflammation and scarring of the liver When the fat builds up enough, it will cause the liver to swell. If the original cause is not from alcohol, it's called nonalcoholic steatohepatitis This disease can impair liver function. Symptoms can be seen with this disease.