Your mental health is your psychological condition. Stress, grief, and lack of sleep can all affect your mental health.
Mental health encompasses the well-being of your mind and emotions. The state of your mental health affects how you get along with other people, how you feel about yourself, and how you handle stressful situations. Conditions like depression and anxiety can damage mental health. Just as you care for your physical health by eating well, drinking water, and sleeping enough, it's important to protect your mental health, too. An earlier, similar term was mental hygiene.