 Population-based studies and case series demonstrate strong associations between NAFLD and several conditions, including obesity, type 2 diabetes, and dyslipidemia, that comprise the metabolic syndrome.4,5,7-13 This suggests that the prevalence of NAFLD is likely to be much greater in these high risk populations. Studies of morbidly obese patients undergoing gastric bypass surgery support this concept. In most of these individuals, liver disease was unsuspected pre-operatively. However, intraoperative liver biopsies consistently demonstrate NAFLD. In four recent series that included over 600 subjects, the prevalence of NAFL steatosis ranged from 30-90 and NASH steatohepatitis was documented in 33-42. Thus, over two-thirds of morbidly obese patients undergoing gastric bypass surgery have NAFLNASH. Although overt manifestations of portal hypertension likely excluded patients as candidates for elective abdominal surgery, these four surgical series consistently identified individuals with hepatic fibrosis. Well-established cirrhosis was relatively unusual, occurring in 1-2 of the group. However, advanced fibrosis was noted in 12 and a third had unexplained periportal fibrosis. There is also a high prevalence of NAFLD is high in populations of patients with type 2 diabetes mellitus. A recent survey of 100 non-alcoholic patients with type 2 diabetes used ultrasonography to screen for NAFLD and demonstrated fatty liver in half of the group. Subsequent liver biopsy revealed NAFL in 12 and NASH in 87 of those with ultrasonographic evidence of fatty liver. Fibrosis or cirrhosis were noted in 20.14 In patients with metabolic syndrome and hyperlipidemia, fatty liver was detected in 50 of 95 adults using ultrasonography to screen for unsuspected hepatic steatosis.15 