Older caregivers of dementia patients have been studied as a model of chronic stress influencing psychological and physical well-being and the function of the immune system. These immune decrements can relate to altered stress hormone levels, and caregivers show elevated or reduced cortisol compared to age-matched controls as well as dysregulation in other cortisol indices. Recently, this field has developed to examine a range of immune outcomes and cortisol measures in younger caregivers too, as well as other potential underlying mechanisms including genetic variation, acute stress reactivity and inflammation. Several interventions have also been trialled to reduce the negative physical impact of caregiving stress. This paper reviews the latest developments in the field and gives suggestions for future research.