Water links the environment, culture, and biology. An integrative approach is needed to attain a complete picture of how water affects human biology due to its inherent interdisciplinary nature. First, this review describes advances in human water needs, thirst, and hydration strategies from a biocultural perspective. Second, it provides a critical appraisal of the literatures on water insecurity (WI) experiences and coping strategies used to mitigate WI to illustrate how they intersect to affect human biology through the embodiment framework. Deviations from water needs and heightened WI can alter hydration and coping strategies, which have implications for a suite of psychological and physiological outcomes. These disruptions are embodied in cellular damage, dehydration, nutrition, stress, mental health, cognitive impairment, aging-related effects, cardiometabolic health, and kidney function. Disrupting forces such as lifestyle changes and climate change have important implications for water needs, WI, coping and hydration strategies, and the embodiment of each. Expected final online publication date for the Annual Review of Anthropology, Volume 52 is October 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.