Yoga is widely practiced as a means to promote physical, psychological and spiritual well-being. While a number of studies have documented the efficacy of yoga for functioning in healthy individuals and those experiencing illness or pain, biopsychosocial effects have not been detailed. We propose an analogue between the physical, psychological and spiritual effects of practice as espoused in yoga traditions, and the biopsychosocial model of health. To this end, we present a review and conceptual model of the potential biopsychosocial benefits of yoga, which may provide clues regarding the possible mechanisms of action of yoga upon well-being. Physical systems activated through yoga practice include musculoskeletal, cardiopulmonary, autonomic nervous system and endocrine functioning. Psychological benefits include enhanced coping, self-efficacy and positive mood. Spiritual mechanisms that can be understood within a Western medical model include acceptance and mindful awareness. We present empirical evidence that supports the involvement of these domains. However, additional well-conducted research is required to further establish the efficacy of yoga for health states, and to understand how posture, breath and meditative activity affect the body, mind and spirit.