Objectives:
The study was aimed at finding out whether, and how, changes in dietary habits would be reflected in anthropometric parameters and body composition.

Methods:
Anthropometric measurements (Martin’s technique) were taken on 52 chronically mentally ill patients, twice: before and a year after diet correction. The patients’ body composition was examined, directly after the measurements, by bioelectric impedance analysis (BIA) in tetragonal arrangement, using a Bodystat ®1500MDD device.

Results:
Changes in dietary habits were reflected in a significant reduction of body weight, BMI, and waist circumference in schizophrenic women; WHR in men with other diseases increased significantly. BMI analysis showed an increase in the percentage of normal-weight schizophrenic women and men, a decrease in the proportion of underweight women and men, and an increase in the proportion of individuals with normal weight suffering from other diseases. Both groups showed beneficial changes in body composition (increased content and percentage of fatless body weight and water, reduced content and percentage of fat tissue). These changes were statistically significant only in men suffering from other diseases and concerned the increased content of fatless body weight.

Conclusions:
Changes in dietary habits enhanced body weight reduction in overweight and obese individuals and resulted in desired changes in BMI, WHR, and body composition. The body fat content was distinctly reduced, with no concurrent changes in the fatless body weight and/or water content. Changes in dietary habits were beneficial for the nutritional status of undernourished patients or those with low body weight.