It might sound strange to talk about inoculating ourselves against stress, but we might be able to do just that. Just as a vaccine safely trains the immune system so it can defend against later attack, researchers think we can do something similar with stress. This idea is often studied in military personnel. Exposing soldiers to simulations of stressful events, while giving them the tools and support to cope, can minimise the impact of future stress. In one study, cadets who received resilience training had lower cortisol levels in later intense military exercises than those who hadn’t received the training. Likewise, paramedics who have received resilience training are also at lower risk of developing post-traumatic stress disorder (PTSD) and depression. Fortunately, most people don’t need military-style training to gain these benefits. Deliberately exposing yourself to manageable, everyday stress can build resilience, says Julie Vašků at Masaryk University in the Czech Republic. Recent research shows that successfully navigating stressful situations remodels the brain, provoking changes across the “stress network”, including the prefrontal cortex, which regulates emotions; …