A remarkable number of lean individuals in the United States suffer from NAFLD, likely due to distinct components of MetS, such as diabetes and/or hypertension.
Indeed, as noticed in the Kangbuk Samsung Health Study, 16,279 non-obese patients with different grades of liver steatosis and fibrosis were at increased risk of sub-clinical atherosclerosis. They are also at higher risk of mortality.
For the European population, the NAFLD Clinical Study Group, a multicentre biopsy-based cohort formed by 515 German patients, reported 12% of these NAFLD patients to be non-diabetic and non-obese.
The occurrence of NAFLD in non-obese subjects remains a challenge and raises several questions regarding the pathophysiological mechanisms governing fat deposition/accumulation in the liver of apparently healthy subjects. A combination of both genetic and non-genetic factors may play a role in this context.