The aim of this research was to investigate the symptoms of muscle dysmorphia (MD) and nutritional status among male gym users. The sample comprised 100 gym male customers who answered the Drive for Muscularity Scale (DMS) and the food habits questionnaire which includes a 24 hours recall. The anthropometric measurements of the participants were also registered. The results showed that 22% of them had symptoms of MD. The diet of males with MD symptoms contained higher quantities of protein than the diet of men without MD symptoms, with a marginally significant difference. Men with MD symptoms attended the gym more times and hours per week and a higher percentage of them used supplements to increase muscular mass in comparison with men without MD symptoms. There were no differences in body composition among groups. These findings suggest that an important percentage of male gym users showed symptoms of MD and their nutritional status is altered by diet composition.