Self-Perceived Caffeine Addiction, Mental Health, and Lifestyle Choices in a Clinic-Based Sample of Young Adults

This study examined associations between self-perceived caffeine addiction severity, mental health, and lifestyle choices in a clinic-based sample of young adults, with consideration of their broader public health implications. A cross-sectional survey was conducted through an internal medicine clinic in Weimar, California, among 1438 individuals aged 18–24 years from diverse cultural backgrounds across 37 countries, 77% of whom were from the United States. Self-perceived caffeine addiction was categorized as none, moderate, or severe. Chi-square analyses showed significant differences across self-perceived caffeine addiction severity groups in all examined lifestyle variables, including dietary factors, physical activity, sleep patterns, sleep and meal regularity, sunlight exposure, entertainment-related screen use, conscience-related behaviors, and substance-use behaviors. One-way analysis of variance (ANOVA) indicated that greater caffeine addiction severity was associated with higher depression and anxiety scores and lower emotional intelligence (EI) scores. Among these mental health indicators, only EI showed a significant association with severe self-perceived caffeine addiction after adjustment. In the adjusted multinomial logistic regression model, sleeping 7–9 h per night; obtaining 1–2 h of sleep before midnight; consuming 3–4 (but not ≥5; a category with only one severe case) servings of fruits, vegetables, and whole grains daily; not reporting tobacco addiction; and having higher EI scores were significantly associated with lower odds of severe self-perceived caffeine addiction. For moderate caffeine addiction, consuming cheese no more than twice per week, viewing entertainment media for two hours or less per week, and not reporting tobacco addiction were associated with lower odds. These findings indicate that self-perceived caffeine addiction severity is associated with poorer mental health and unhealthy lifestyle behaviors, supporting the need for a holistic approach to prevention and intervention.