Making and keeping friends. This one belongs more to mental and emotional health rather than physical health. Exercise is a major part of physical health, though, and not getting enough of it is associated with various diseases. Eating well and drinking water are the basis for biological life, so clearly they’re necessary for health. And sleep is indispensable, too – an underrated necessity.
Friendship is more of a mental health need than a physical health need. The two areas are related, though! Poor emotional health has serious physical consequences including malnutrition, weight fluctuations, and sleep problems. Medical professionals have to take mental health just as seriously as physical health, or they may encounter physical symptoms that they’re unable to explain or treat.