Mental Illness and Adults
In 2015, there were an estimated 43.4 million adults –about 1 in 5 Americans aged 18 or older – with a mental illness within the previous year. 
In 2015, there were an estimated 9.8 million adults – about 1 in 25 Americans aged 18 or older – with serious mental illness. “Serious mental illness” is defined as individuals experiencing within the past year a mental illness or disorder with serious functional impairment that substantially interferes with or limits one or more major life activities. 
Mental Illness and Children and Teens
Just over 20% – or 1 in 5 – children, have had a seriously debilitating mental disorder. 
Half of all chronic mental illness begins by age 14 and three-quarters begin by age 24. 
Number of visits to physician offices with mental disorders as the primary diagnosis: 65.9 million. 
In 2015, 75% of children aged 4 to 17 received treatment for their mental disorders within the past year. 
Impact of Mental Illness
Suicide, which is often associated with symptoms of mental illness, is the 10th leading cause of death the U.S. and the 2nd leading cause of death among people aged 15-34.9
Serious mental illness costs in the United States amount to $193.2 billion in lost earnings per year. 
Mood disorders, including major depression, dysthymic disorder, and bipolar disorder, are the third most common cause of hospitalization in the United States. for both youth and adults aged 18 to 44. 
Individuals living with serious mental illness face an increased risk of physical health problems, such as heart disease, diabetes, and HIV (human immunodeficiency virus, the virus that causes AIDS). 
U.S. adults living with serious mental illness die on average 25 years earlier than others, largely due to treatable medical conditions. 
Mental Health Promotion and Prevention
Preventing mental illness and promoting good mental health involves actions to create living conditions and environments that support mental health and allow people to adopt and maintain healthy lifestyles. These include a range of actions to increase the chances of more people experiencing better mental health, such as 
Early childhood interventions (for example, home visits for pregnant women and programs that help young children build social and emotional skills).
Social support for elderly persons.
Programs targeted to people affected by disasters or other traumatic events.
Mental health interventions at work (for example, stress prevention programs).
Violence prevention strategies (for example, reducing violence in the community and the home).
Campaigns to change the culture of mental health so that all of those in need receive the care and support they deserve.
Content source: Centers for Disease Control and Prevention
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