Immune cell function and fate are intimately linked to engagement of metabolic pathways. The contribution of core metabolic pathways to immune cell bioenergetics has been vigorously investigated in recent years. However, precisely how other peripheral metabolic pathways support immune cells beyond energy generation is less well understood. Here we survey the literature and highlight recent advances in our understanding of several ancillary metabolic pathways and how they support processes beyond ATP production and ultimately contribute to protective immunity.