Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the United States. It can be broadly sub-classified into nonalcoholic fatty liver (NAFL), which is thought to have minimal risk of progression to cirrhosis, and nonalcoholic steatohepatitis (NASH), which is thought to have an increased risk of progression to cirrhosis. The current diagnostic gold standard for differentiating whether a patient with NAFLD has NAFL versus NASH is liver biopsy. However, liver biopsy is an invasive procedure, which is limited by sampling variability, cost, and may be complicated by morbidity and even death, although rare. Accurate, non-invasive, biomarkers for the detection of liver disease and liver disease progression e.g., progression to NASH, are currently also not available.