What is mental illness?

Mental illnesses are conditions that affect a person’s thinking, feeling, mood or behavior, such as depression, anxiety, bipolar disorder, or schizophrenia. Such conditions may be occasional or long-lasting (chronic) and affect someone’s ability to relate to others and function each day.


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What is mental health?

Mental health includes our emotional, psychological, and social well-being. It affects how we think, feel, and act. It also helps determine how we handle stress, relate to others, and make healthy choices.1 Mental health is important at every stage of life, from childhood and adolescence through adulthood.

Although the terms are often used interchangeably, poor mental health and mental illness are not the same things. A person can experience poor mental health and not be diagnosed with a mental illness. Likewise, a person diagnosed with a mental illness can experience periods of physical, mental, and social well-being.


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Why is mental health important for overall health?

Mental and physical health are equally important components of overall health.  Mental illness, especially depression, increases the risk for many types of physical health problems, particularly long-lasting conditions like stroke, type 2 diabetes, and heart disease. Similarly, the presence of chronic conditions can increase the risk for mental illness.2


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Can your mental health change over time?

Yes, it’s important to remember that a person’s mental health can change over time, depending on many factors.  When the demands placed on a person exceed their resources and coping abilities, their mental health could be impacted. For example, if someone is working long hours,Cdc-pdf caring for an ill relative or experiencing economic hardship they may experience poor mental health.


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How common are mental illnesses?

Mental illnesses are among the most common health conditions in the United States.


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What causes mental illness?

There is no single cause for mental illness. A number of factors can contribute to risk for mental illness, such as

https://www.cdc.gov/mentalhealth/learn/index.htm#:~:text=It%20affects%20how%20we%20think,others%2C%20and%20make%20healthy%20choices.&text=Mental%20health%20is%20important%20at,childhood%20and%20adolescence%20through%20adulthood.