White adipose tissue (WAT) is exposed to pathogens that breach epithelial barriers, but the role of adipose T cells in immunity isn’t clear. In this issue of Immunity, find that WAT harbors a reservoir of memory T cells that provide antimicrobial immunity at the expense of lipid synthesis and metabolism. : White adipose tissue (WAT) is exposed to pathogens that breach epithelial barriers, but the role of adipose T cells in immunity isn’t clear. In this issue of Immunity, Han et al. (2017) find that WAT harbors a reservoir of memory T cells that provide antimicrobial immunity at the expense of lipid synthesis and metabolism.