The patients will undergo biochemical evaluation in which the serum lipids, the levels of oxidative stress and the antioxidant capacity will be assessed. Body composition will be calculated with anthropometric measurements, while the levels of visceral fat, the subcutaneous fat, as well as the level of liver fat infiltration will be examined with the use of computed tomography images. Factors related to the patients' quality of life will be assessed by a series of questionnaires.