The release of the “feel-good” chemicals dopamine, serotonin, endorphins, and oxytocin are tied to specific lifestyle, exercise, and dietary choices. Here’s what triggers each one.

Shopping list. Meat, fish and poultry 400g/14oz thick skinless fish fillets, such as cod loin 2 fresh salmon fillets (around 280g/10oz) 10–12 boneless, skinless chicken thigh fillets 500g/1lb ...