Objective. To compare the characteristics, health behaviors, and health services utilization of U.S. adults who use complementary and alternative medicine (CAM) to treat illness to those who use CAM for health promotion. Data Source. The 2007 National Health Interview Survey (NHIS). Study Design. We compared adult (age ≥18 years) NHIS respondents based on whether they used CAM in the prior year to treat an illness (n=973), for health promotion (n=3,281), or for both purposes (n=3,031). We used complex survey design methods to make national estimates and examine respondents' self-reported health status, health behaviors, and conventional health services utilization. Principal Findings. Adults who used CAM for health promotion reported significantly better health status and healthier behaviors overall (higher rates of physical activity and lower rates of obesity) than those who used CAM as treatment. While CAM Users in general had higher rates of conventional health services utilization than those who did not use CAM; adults who used CAM as treatment consumed considerably more conventional health services than those who used it for health promotion. Conclusion. This study suggests that there are two distinct types of CAM User that must be considered in future health services research and policy decisions.