According to the National Alliance on Mental Illness, "A mental illness is a condition that affects a person's thinking, feeling or mood. Such conditions may affect someone's ability to relate to others and function each day. Each person will have different experiences, even people with the same diagnosis. "
The impact of Mental health conditions according to the World Health Organization "include mental disorders and psychosocial disabilities as well as other mental states associated with significant distress, impairment in functioning or risk of self-harm.
In 2019, 970 million people globally were living with a mental disorder, with anxiety and depression the most common. Mental health conditions can cause difficulties in all aspects of life, including relationships with family, friends and community. They can result from or lead to problems at school and at work.
Globally, mental disorders account for 1 in 6 years lived with disability. People with severe mental health conditions die 10 to 20 years earlier than the general population. And having a mental health condition increases the risk of suicide and experiencing human rights violations.
The economic consequences of mental health conditions are also enormous, with productivity losses significantly outstripping the direct costs of care."
https://www.who.int/health-topics/mental-health#tab=tab_1
https://www.nami.org/get-involved/