Background and Study Aim. Regular exercise has a positive effect on physical, psychological, and social health. However, excessive participation in exercise and the need for compulsive exercise can lead to exercise addiction. This addiction may result in several issues, including injuries, unhealthy eating behaviors, and negative attitudes. To prevent these potential problems, it is important to identify the extent of exercise addiction among individuals who exercise regularly. In this regard the study aims to examine the potential relationships between exercise addiction, muscularity-oriented eating and belief levels in sports nutritional supplements among students. Material and Methods. The study included 377 participants with a mean age of 24.46 ± 6.18. All participants had been exercising regularly for at least one year, with a frequency of two days per week. Data were collected using a demographic form, the Exercise Addiction Scale, the Muscularity-Oriented Eating Test (MOET), and the Sport Nutritional Supplements Belief Scale. Results. The findings suggest that 84.6% of the participants may be classified as dependent on exercise addiction. There is a low-level but significant positive relationship between exercise addiction and muscularity-oriented eating levels (r = 0.189, p < 0.001). A similar relationship exists between exercise addiction and beliefs in sports nutrition supplements (r = 0.179, p < 0.001). Furthermore, a moderately significant positive relationship was found between muscularity-oriented eating and beliefs in sports nutrition supplements (r = 0.361, p < 0.001). Analyses based on exercise addiction levels revealed notable differences. The dependent group showed higher levels of muscularity-oriented eating compared to the risk group. They also exhibited stronger beliefs in sports nutrition supplements. Conclusions. Regular exercise among students leads to a higher likelihood of developing exercise addiction. Exercise addiction is associated with muscularity-oriented eating behaviors and strong beliefs in the efficacy of sports nutritional supplements. These behavioral patterns increase the risk of potential health issues related to excessive exercise and unhealthy dietary practices. Providing education on the effects of exercise, proper nutrition, and the responsible use of nutritional supplements is essential to mitigate these risks and promote healthier habits.