Informal care provision is an activity in which individuals are increasingly likely to become involved across their life course, and particularly in later life, as a result of demographic changes such as increasing longevity and changes in co-residential living arrangements in later life. Academic research so far has highlighted the adverse impact of informal care provision on the financial position of the carer, however, the evidence on the impact of informal care provision on the carer's physical, mental and emotional health, and on their mortality, presents a more complex picture. This paper reviews research from the UK and beyond on the provision of informal care and its subsequent impact on health and mortality outcomes. Two key findings emerge from this review paper. Firstly, the cross-sectional analysis of data shows mixed associations between informal care provision and poor health outcomes for the carer. Such research highlights the importance of the demographic and socio-economic characteristics of the carer and the person cared for, and of the specific characteristics and nature of the care provided (e.g. duration, level). Secondly, longitudinal analysis, which typically benefits from a longer timeframe to follow up the impact of caring, shows that although informal care provision is not per se associated with adverse health and mortality outcomes, nevertheless particular types and durations of caring have shown negative outcomes.