Hypocaloric diet is a key component of the weight-reducing treatment of obesity and obesity-related disorders. Hypocaloric diets and the associated weight reduction promote improvement of metabolic profile of obese individuals. Among the mechanisms that underlie this beneficial metabolic outcome, the diet-induced modifications of morphological and functional characteristics of human adipose tissue (AT) are believed to have an important role. Prospective studies of hypocaloric weight-reducing dietary intervention demonstrate effects on adipocyte metabolism, namely lipolysis and lipogenesis, and associated changes of the adipocyte size. The endocrine function of AT, which involves cytokine and adipokine production by adipocytes, as well as by cells of stromavascular fraction, is also regulated by dietary intervention. Related inflammatory status of AT is modulated also as a consequence of the changes in recruitment of immune cells, mainly macrophages, in AT. Here, we give an overview of metabolic and endocrine modifications in human AT induced by a variety of hypocaloric diets.