Frontotemporal dementia (FTD) has traditionally been regarded as a disease of cognition and behavior, but emerging evidence suggests that the disease also affects body functions including changes in eating behavior and metabolism, autonomic function, sleep behavior, and sexual function. Central to these changes are potentially complex neural networks involving the hypothalamus, with hypothalamic atrophy shown in behavioral variant FTD. The physiological changes found in FTD are reviewed and the key neural networks and neuroendocrine changes mediating these changes in function discussed, including the ability to use these changes as biomarkers to aid in disease diagnosis, monitoring disease progression, and as potential treatment targets.