Background: Constitutional thinness is characterized by a low body mass index, the absence of signs of under nutrition and is still misdiagnosed as anorexia nervosa. This rare entity was most often described in European countries. Data concerning their nutritional and psychological profile are missing in other populations or cultures, especially in the Middle East. Objectives: The aim of this study was to assess the psychological, nutritional, and hormonal status in a group of Lebanese constitutionally thin adults in comparison with a control group. Methods: A cross-sectional study was carried ...