Background Insulin resistance can result from various genetic and lifestyle factors. Initially, symptoms of insulin resistance may not be readily noticeable, but as the condition progresses, individuals may start experiencing symptoms. This study aimed to investigate the factors contributing to the development of insulin resistance among medical students at a private college in Saudi Arabia. Methodology We conducted a cross-sectional study using a convenient non-probability sampling technique, with a sample size of 241 participants. We employed validated questionnaires to gather information on physical activity, sleep, dietary habits, and stress. Specifically, we used the International Physical Activity Questionnaire (IPAQ)-Short Form for assessing physical activity, the Single-Item Sleep Quality Scale (SQS) for evaluating sleep quality, the Healthy Eating Quiz (HEQ) to gauge dietary patterns, and the stress questionnaire designed by the International Stress Management Association (ISMA) to measure stress levels. Additionally, we collected anthropometric measurements, as well as systolic and diastolic blood pressure readings. We calculated prevalence using percentages and employed the chi-square test to analyze variables, with a significance level set at p-values <0.05. Results This study investigated risk factors associated with lifestyle, focusing on waist circumference as an indicator of insulin resistance. Our findings revealed that a majority of individuals with high waist circumference were physically inactive and more susceptible to stress, and this difference was statistically significant when compared to those with normal waist circumference. Additionally, we observed that sleep deprivation and poor nutrition were more prevalent among individuals with high waist circumference, although these differences were not statistically significant. Conclusions This study highlights a high prevalence of elevated waist circumference, indicating insulin resistance, among medical students. Furthermore, it underscores the significant presence of well-known risk factors associated with insulin resistance within this population of medical students.