This issue of “Postępy Nauk Medycznych” focuses on various aspects of obesity. We present empirical papers and conceptual studies with the aim of passing knowledge to doctors, who in their daily practice deal with this complex condition, which impair health and have serious negative social and psychological results.

The first group of articles consists of empirical studies from centers where patients with morbid obesity are treated daily and where research is conducted regularly. These papers are very interesting and important because they hint at the pathology of obesity, show us its possible health and psychological effects, which can be succesfully diminished after body mass reduction. Directions for practicing medical doctors are presented, both in their ambulatory and hospital work.

The first article written by Walicka et al. presents results of their work on gender dependent dimorphism in adipokines levels and its correlations with insulin resistance in extremely obese patients (1). The authors, based on their results, concluded that in extremely obese patients there is a gender dependent dimorphism in adipokines levels and their correlations with insulin resistance. This dimorphism is not fully understood and it might be due to different adipose tissue distribution.

The next article “Nonalcoholic fatty liver disease in patients with morbid obesity” was written by Lisik et al. (2). The aim of this study was to assess the prevalence of nonalcoholic fatty liver disease (NAFLD), biochemical abnormalities accompanying this pathology, as well as the development of diagnostic method allowing the prediction of NAFLD or nonalcoholic steatohepatitis (NASH) among pathologically obese patients. The authors on the basis of their retrospective material with biochemical parameters concluded that NAFLD occurs in most patients awaiting bariatric surgery. These data are very important because logistic regression model that applies biochemical parameters allows prediction of the occurrence of obesity-related histological changes in the liver, without the need for performing the liver biopsy.

The paper written by Dziurowicz-Kozłowska et al. deals with physical, psychological and social functioning of patients undergoing surgical treatment of obesity with the Vertical Banded Gastroplasty (VBG) (3). The paper has been set in the bio-psychosocial health model and it confirms that obesity impacts the patients’ psychological functioning. Conclusions state thatthe VBG surgery is effective in obtaining a body mass reduction, improvement in obese patients’ physical and psychological functioning (after 3 months) as well social functioning (after six months). Such conclusions support the chirurgical treatment of obesity.