Prepared by Dr. Meagan Gray, a gastroenterologist with specialties in gastroenterology, hepatology , and liver transplantation
Nonalcoholic fatty liver disease (NAFLD) encompasses a spectrum of disorders ranging from simple steatosis to steatohepatitis and cirrhosis. NAFLD is the most common cause of chronic liver disease worldwide, affecting approximately 25% of the adult population globally (1) and 31% of adults in the United States (2). It is currently the second most common indication for liver transplantation (3), and the second most common cause of hepatocellular carcinoma (HCC) in patients awaiting liver transplantation in the US (4). The diagnosis of NAFLD requires >5% hepatic steatosis with lack of secondary causes for hepatic fat accumulation. Approximately 25% of patients with NAFLD will have nonalcoholic steatohepatitis (NASH), which is associated with a 20% risk of progression to cirrhosis (1, 5). Projections estimate that prevalent NAFLD and NASH cases will increase to 100.9 and 27 million by 2030, and incidence of decompensated cirrhosis, HCC, and liver-related deaths due to NAFLD will increase to 105,430, 12,240, and 78,300, respectively (6). Patients at highest risk for developing NAFLD are those with obesity and features of the metabolic syndrome. It is estimated that between 40–70% of patients with diabetes mellitus (DM) have NAFLD (1, 7, 8), as well as up to 67% of adults with a body mass index (BMI) between 25–30 kg/m2 and up to 91% of adults with a BMI >30 kg/m2 (9–13). Due to lack of approved pharmacologic treatment, current treatment recommendations are for weight loss of >10% total body weight, which is associated with NASH resolution and fibrosis regression (14). Weight loss of even 5% can stabilize or improve fibrosis in 94% of cases. Specific dietary recommendations are to reduce or eliminate processed foods, high fructose corn syrup, concentrated sugars, and saturated fat from the diet (15, 16, 17).
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