According to Italians, you cannot leave the house with wet hair or you’ll get a cervicale (neck pain with a severe headache) or jump into the pool right after having lunch unless you want to have indigestione (indigestion).
Another commonly shared opinion, contingent on climatic conditions: “Are you crazy? There is no way I am going to Bologna with this heat, I will die from an insolazione (sunstroke)!”