Incorrect weight control or weight loss practices in the adolescence period in which growth and development is at its highest speed can affect health in a negative way. In this research, it is aimed to determine the practices of adolescents related to maintaining body weight or losing weight. The research has been conducted in public primary and secondary schools located in 5 different regions of Turkey. A total of 826 adolescents of which 358 are boy and 468 are female students between the ages of 13 and 18, have been included in the research. Data has been gathered and statistically evaluated by applying a survey form to adolescents where demographic information and diet practices take place. It has been determined that 38.5% of adolescents had previously attempted practices related to weight maintenance or weight loss, and the most practiced three methods are respectively limitation on food consumption (71.1%), selecting low fat food (67.0%), and skipping meals (38.7%). No statistically significant difference was found between the behaviors of weight maintenance/loss according to genders, and boys were reported to use illegal weight-loss medication at higher rates. It has been determined that a majority of the adolescents haven't received any professional support and that they choose to practice a diet obtained from someone else or through the media. In conclusion, adolescents should be informed about healthy dieting practices by experts in terms of creating healthy generations.