Implicit theories of health refer to people's assumptions about the malleability of health, that is, whether health is perceived as changeable (incremental theory) or fixed (entity theory). The influence of implicit theories on health promotion is widely neglected in existing models of health behavior change (e.g., Health Action Process Approach, Social Cognitive Theory). Reviewing past research, I will show that findings so far suggest that a stronger incremental theory (i.e., assuming that a given characteristic is changeable) is positively related to numerous health-promoting outcomes. The main part of this work will present eight additional studies. These studies provide further correlational, experimental, and interventional support for the importance of incremental theories of health for health promotion. Based on the reviewed literature and the presented findings, I derive a conceptual model that describes the relationship between implicit theories and other cognitions that are relevant for health promotion (locus of control, outcome expectancy, and self-efficacy). This model can guide further research on implicit theories and explains how the included constructs interact to affect health promotion. Finally, limitations and implications to the presented research are discussed to improve future research on implicit theories. Accordingly, research on implicit theories should pay more attention to a precise distinction from related constructs (like locus of control). However, at the same time, it is relevant to examine the relationships between these constructs more closely to explain how implicit theories impact health promotion.