The first step in finding out if you have fatty liver disease is to see a doctor who is skilled with palpation — a method of diagnosis by manual examination and pressure.

A doctor who is well-practiced in this kind of diagnosis can distinguish a normal liver from an abnormal one by touch alone.

Most patients with fatty liver disease do not have symptoms or pains directly related to the liver (in the right upper abdomen). Common symptoms include fatigue and occasional nausea or stomach upset.

Occasionally, patients will complain of vague right upper abdominal pain. Nonalcoholic fatty liver disease can only be diagnosed in a patient who does not drink excessive alcohol or have Hepatitis B or C.
A diagnosis of NAFLD can be made by radiological procedures such as ultrasound, CT, or MRI.

However, these tests cannot distinguish between NAFLD and nonalcoholic steatohepatitis (NASH), nor can they identify inflammation in the liver.

An ultrasound test is required to diagnose NAFLD in the vast majority of patients. A diagnosis can also be confirmed by a liver biopsy.