Mental Health Disorders

Mental health disorders, such as depression or anxiety, affect the way we think, feel and behave. There are more than 200 types of mental illnesses. Symptoms of mental health disorders usually improve with treatment, which may include medication, psychotherapy, alternative therapies or brain stimulation therapy.


What is mental health and why is it important?

Behavioral health (sometimes called mental health) includes a person’s psychological, emotional and social wellbeing. It shapes the way you think, feel, behave and interact with others. Your mental state also affects how you cope with stress. It’s a vital part of your life, from infancy through adulthood.


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What is a mental health disorder?

Mental (behavioral) health disorders, or mental illnesses, affect the way you think and behave. They change your mood and can make it difficult to function at home, work, school or in your community.

It’s important to note that having poor mental health doesn’t always mean you have a behavioral health disorder. You can also have a behavioral health disorder and still go through long periods of good mental health.

Are there different types of mental health disorders?

There are more than 200 types of mental health disorders. A few of the most common types of mental health disorders include:


Who gets mental health disorders?

Anyone of any age, sex, background or ethnicity can get a behavioral health disorder. People designated female at birth (DFAB) more commonly experience depression, anxiety and eating disorders. While people designated male at birth (DMAB) are more likely to experience substance abuse and antisocial personality disorders. Behavioral problems and ADHD are more common in adolescents.

How common are behavioral health disorders?

Behavioral health disorders are common in the United States. About 1 in 5 adults and adolescents live with a mental health disorder. About half of all mental illnesses begin by age 14 and three-quarters begin by age 24.

Suicide, which is often associated with mental illness, is the 10th leading cause of death in the U.S. It’s the second leading cause of death among people ages 15 to 34.


Symptoms and Causes

What causes mental health disorders?

Behavioral health disorders can have many causes. They might be the result of abnormal genes. You may inherit those genes from a parent, or genes can change during your life. Chemical imbalances in your brain can also lead to mental illness.

Your risk of mental illness increases if you:

  • Use alcohol or recreational drugs.
  • Don’t get proper nutrition.
  • Don’t have a support system of friends or family members.
  • Had a traumatic birth or were born from a high-risk pregnancy.
  • Have a chronic medical condition such as cancer, diabetes or hypothyroidism.
  • Have a family history of behavioral health disorders.
  • Have a neurological disorder such as Alzheimer’s disease or dementia.
  • Have a sleep disorder.
  • Have extreme stress in your life.
  • Have had a traumatic brain injury.
  • Have had a traumatic life event or a history of abuse.
  • Struggle with your spirituality or beliefs.

What are the symptoms of a behavioral health disorder?

Mental health disorders can lead to a broad range of symptoms, including:

  • Use of recreational drugs or alcohol.
  • Avoiding social situations and friends.
  • Changes in sex drive.
  • Difficulty perceiving reality, including having delusions or hallucinations.
  • Excessive worrying or fear.
  • Fatigue or sleep problems.
  • Feelings of sadness or isolation.
  • Inability to gauge or interpret other people’s feelings or emotions.
  • Intense irritability or anger.
  • Obsession with your physical appearance, weight or eating habits.
  • Problems concentrating, learning or completing everyday tasks.
  • Sudden mood changes, going from “lows” to “highs.”
  • Suicidal thoughts or self-injury.

Behavioral health disorders in children tend to affect their functioning. You might notice:

  • Changes in their performance at school, or how they interact with other children.
  • Disinterest in activities or hobbies they used to enjoy.
  • Excessive worry or anxiety, such as fear of going to bed.
  • Frequent temper tantrums, disobedience or aggression.
  • Hyperactive behavior, such as problems concentrating or sitting still.
  • Nightmares.

Diagnosis and Tests

How are mental health disorders diagnosed?

It’s important to get a diagnosis from a healthcare provider who specializes in behavioral health disorders. You need an accurate diagnosis to receive the right treatment.

A healthcare provider will carefully review your symptoms to evaluate your mental health. Be sure to tell your healthcare provider:

  • If there are any specific triggers that make your mental health worse.
  • If your mental health problems are chronic (ongoing) or if they come and go.
  • When you first noticed changes in your mental health.

There aren’t any medical tests that can diagnose mental illnesses. But your healthcare provider may perform tests, such as blood work or imaging exams, to rule out other conditions that can affect mental health.

Management and Treatment

How are mental health disorders treated?

Treatments for mental health disorders may include:

  • Medication: Some mental illnesses respond well to medication, such as antidepressants and antipsychotics. These medicines change the chemicals in your brain, so you experience fewer symptoms. It’s very important to take medication exactly as your healthcare provider directs. Never stop taking medication for a mental illness without consulting your healthcare provider.
  • Psychotherapy: Talking to a mental health professional can help you work through the challenges of an illness and manage its symptoms. Psychotherapy can be in a one-to-one setting with a healthcare provider or a group setting. Cognitive behavioral therapy (CBT) is a form of psychotherapy. It focuses on helping you change negative behaviors and thought patterns.
  • Alternative therapies: Some mental illnesses, such as depression, may improve with alternative therapies. Examples include herbal remedies, massage, acupuncture, yoga and meditation. Talk to your healthcare provider before taking any herbal remedies or supplements. They may affect other medications.
  • Brain stimulation therapies: Not all disorders improve with medication. If that’s the case, your healthcare provider may recommend brain stimulation therapies. These treatments change the way nerves and other cells in your brain process chemicals and respond to stimuli. Examples include electroconvulsive therapy and transcranial magnetic stimulation (TMS).


Are behavioral health disorders preventable?

There’s no way to prevent a behavioral health disorder. But you can manage symptoms better with the help of a healthcare provider. Contact them as soon as you notice there’s a problem.

Outlook / Prognosis

What’s the prognosis (outlook) for people with a behavioral health disorder?

Most people with behavioral health disorders can manage their symptoms. They lead full, fulfilling lives with the right treatments. Some people will need to manage a mental illness for the rest of their lives. Others find that symptoms improve as they get older. Overall, mental illnesses tend to peak in young adults ages 18 to 25, then diminish greatly after 50. Mental illness can also increase your risk for certain health conditions such as stroke, Type 2 diabetes and cardiovascular disease.

Living With

When should I contact my doctor?

Get help right away if you’re having suicidal thoughts or notice suicidal behavior in someone else. You can call the Suicide and Crisis Lifeline at 988. This hotline connects you to a national network of local crisis centers that provide free and confidential emotional support. The centers support people in suicidal crisis or emotional distress 24 hours a day, seven days a week. In an emergency, call 911.

A note from Cleveland Clinic

Behavioral health disorders, which affect about 20% of people in the U.S., impact how you think, feel and behave. They can make it difficult to function at home, school or work. But there are treatments. Getting an accurate diagnosis is the first step toward managing a mental health disorder. Talk to your healthcare provider if you or your child show any signs or symptoms.

Medically Reviewed

Last reviewed on 01/24/2022.

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