Background: Understanding the state of the science linking meaning, purpose, and spirituality (MPS) to health outcomes is key to advancing the integration of MPS into lifestyle medicine. Objective: This review aimed to summarize existing research on the use of MPS in lifestyle medicine and healthcare, emphasizing gaps and proposing directions for future research. Methods: A narrative literature review of articles abstracted in PubMed was conducted in conjunction with an in-person summit on MPS and lifestyle medicine in March 2025. This narrative review was organized around the existing science linking MPS to health outcomes, measures of MPS, potential mechanisms accounting for the links between MPS and health outcomes, MPS interventions, potential moderators of the effects, and directions for future research. Results: There are consistent, small to moderate effects that link MPS to increased longevity, improved physical and mental health, and better well-being. Several psychometrically supported measures of MPS exist. Interventions incorporating MPS, especially for populations with advanced illnesses, show promise to improve health and well-being. MPS likely contributes to health through several biopsychosocial pathways. Conclusion: Future work is needed to examine the impact of implementing MPS into lifestyle medicine practice, using rigorous methods, and evaluating its effect on patient outcomes.