Research has revealed relationships among a wide range of substance use behaviors, including smoking, alcohol use, and drug use. To investigate whether a substance use factor emerges when different indicators of substance use, different samples, and three health related issues, (i.e., meal regularity, exercise and hours of sleep) are examined, the patterns of substance use in 226 New England high school students (93 males, 127 females, and 6 unidentified), with a mean age of 16, and in 199 Southern California college students (123 females, 76 males), with a mean age of 21, were studied using an extensive survey questionnaire. The questionnaire assessed meal regularity, drug use, alcohol use, smoking, exercise, and sleep. An analysis of the results showed that drug use, alcohol use, and smoking were significantly related in all four subsamples: high school males and females; and college males and females. Factor analysis indicated that drug use, alcohol use, and smoking formed a cohesive substance use factor, suggesting that different forms of substance use may be attributable to similar motives and that these behaviors may serve related functions for those who engage in them. Although meal regularity, exercise, and hours of sleep failed to show a consistent pattern of relationship, meal regularity did correlate with less drug use and more hours of sleep in all groups except college males. (BL)