There are great health disparities in the world today, both between countries and within them. This problem might be seen as related to the access to various kinds of capabilities. It is not fully clear, however, what the exact relation is between health and capabilities. Neither Amartya Sen nor Martha Nussbaum has explicitly formulated a theory of health to go with their theories of capabilities. This paper attempts to present a clarification of the conceptual relation between health and capabilities. Health, it is argued, should be seen as a holistic multi-dimensional phenomenon, made up of basic abilities and subjective well-being, and of fundamental states and processes. Using this theory, the paper shows how health is related to Nussbaum's ten capabilities. It is argued that health, in the senses described, is a necessary part of all ten capabilities. Moreover, some of the capabilities on Nussbaum's list, such as thinking and imagining, and practical reasoning, refer to health. Finally, it is shown that even though health is part of all capabilities, health cannot itself primarily be seen as a capability. An acceptable degree of health is required as a functioning for any theory of human flourishing to be reasonable.