This paper explores the relationship between unpaid domestic labour and health. Although the 'informal care' literature touches on the connection between aspects of domestic labour and health, sociologists have not engaged in a systematic analysis of the nature of this relationship. In the following discussion I examine i) the reasons why this relationship has been obscured, ii) possible ways forward in theorising the link and, iii) the under-recognised historical contribution made by domestic labourers to the improvement in the health status of the population in industrial Britain. In relation to the latter I critically examine the widely accepted 'McKeown thesis' (McKeown 1979) which postulates that falling mortality rates in late 19th and early 20th century Britain can be explained not by medical intervention but by rising standards of living and improved nutrition. I argue that in the McKeown thesis, and in the work of those like David Blane (1987) who have examined it, the explanation for falling mortality rates is incomplete because it has not accounted for a then developing and expanding area of social activity, namely, domestic labour.