Facts you should know about mental health and mental illness

  • Mental health is more than just being free of a mental illness. It is more of an optimal level of thinking, feeling, and relating to others.
  • Mentally healthy individuals tend to have better medical health, productivity, and social relationships.
  • Mental illness refers to all of the diagnosable mental disorders and is characterized by abnormalities in thinking, feelings, or behaviors.
  • Some of the most common types of mental illness include anxiety, depressive, behavioral, and substance-abuse disorders.
  • There is no single cause for mental illness. Rather, it is the result of a complex group of genetic, psychological, and environmental factors.
  • While everyone experiences sadness, anxiety, irritability, and moodiness at times, moods, thoughts, behaviors, or use of substances that interfere with a person's ability to function well physically, socially, at work, school, or home are characteristics of mental illness.
  • There is no one test that definitively indicates whether someone has a mental illness. Therefore, health-care practitioners diagnose a mental disorder by gathering comprehensive medical, family, and mental-health information.
  • Talk therapy (psychotherapy) is usually considered the first line of care in helping a person with a mental illness. It is an important part of helping individuals with a mental disorder achieve the highest level of functioning possible.
  • Psychotherapies that have been found to be effective in treating many mental disorders include family focused therapy, psycho-education, cognitive therapy, interpersonal therapy, and social rhythm therapy.
  • Medications may play an important role in the treatment of a mental illness, particularly when the symptoms are severe or do not adequately respond to psychotherapy.
  • A variety of factors can contribute to the prevention of mental-health disorders.
  • Individuals with mental illness are at risk for a variety of challenges, but these risks can be greatly reduced with treatment, particularly when it is timely.

Mental Illness in Children

Mental disorders in children are quite common and sometimes severe. About one-fourth of children and teens experience some type of mental disorder in any given year, one-third at some time in their lives. The most common kind of mental disorders are anxiety disorders, like generalized anxiety disorder (formerly called overanxious disorder of childhood) or separation anxiety disorder. Other common types of mental illnesses in childhood include behavior disorders like attention deficit hyperactivity disorder (ADHD), mood disorders like depression, and substance-use disorders like alcohol use disorders. Statistics indicate how relatively common these disorders occur. ADHD affects 8%-10% of school-aged children. Depression occurs at a rate of about 2% during childhood and from 4%-7% during adolescence, affecting up to about 20% of adolescents by the time they reach adulthood. In teens more frequently than in younger children, addictions, eating disorders, bipolar disorder, and less often early onset schizophrenia may manifest.

What is mental health?

Although it might seem easy to define mental health as the absence of mental illness, most experts agree that there is more to being mentally healthy. The U.S. Surgeon General has defined mental health as "a state of successful performance of mental function, resulting in productive activities, fulfilling relationships with people, and the ability to adapt to change and to cope with adversity." The state of being mentally healthy is enviable given the advantages it affords. For example, mentally healthy adults tend to report the fewest health-related limitations of their routine activities, the fewest full or partially missed days of work, and the healthiest social functioning (for example, low helplessness, clear life goals, high resilience, and high levels of intimacy in their lives).

What is mental illness?

Mental illness refers to all of the diagnosable mental disorders. Mental disorders are characterized by abnormalities in thinking, feelings, or behaviors. Highly common, about 46% of Americans can expect to meet the formal diagnostic criteria for some form of anxiety, depressive, behavioral, thought, or substance-abuse disorder during their lifetime.


Panic attacks are repeated attacks of fear that can last for several minutes. See Answer

What are common types of mental illness?

Some of the most common types of mental illness include anxiety, depressive, behavioral, and substance-abuse disorders. Examples of anxiety disorders include phobias, panic disorder, generalized anxiety disorder (GAD), social anxiety disorder, and obsessive compulsive disorder (OCD). Anxiety disorders are characterized by excessive worry to the point of interfering with the sufferer's ability to function. Examples of anxiety disorders include the following:

  • Phobias: involve severe, irrational fear of a thing or situation. Examples of phobias include fear of heights (acrophobia), spiders (arachnophobia), and of venturing away from home (agoraphobia).
  • Social anxiety disorder is the fear of being in social situations or feeling scrutinized, like when speaking in public.
  • Generalized anxiety disorder (GAD) tends to result in the person either worrying excessively about many aspects of their life (like about money, family members, the future) or having a free-floating anxiety that is otherwise hard to describe. GAD is quite common, affecting about 10% of the population.
  • Panic disorder is characterized by recurring episodes of sudden, severe, debilitating anxiety (panic) attacks that are immobilizing. Those episodes usually include symptoms like racing heartbeat, shortness of breath, stomach upset, and trouble thinking. In order to be diagnosed as having panic disorder, the person must also either worry about having another attack or about what the attack means (for example, wondering if the symptoms of panic indicate they are having a heart attack).

Behavioral disorders (like attention deficit hyperactivity disorder [ADHD], oppositional defiant disorder, or conduct disorder) are characterized by problems conforming to the tenets of acceptable behavior. The most common behavior disorder is ADHD; this condition includes symptoms of inattention and/or hyperactivity and impulsivity. While it used to be considered primarily a disorder of boys, it is now understood to be just as likely to occur in girls and that it can persist into adulthood in about half of children with ADHD.

Dementia, including Alzheimer's dementia, is characterized by a problem with thinking, involving both memory problems and other forms of thinking. These are also known as cognitive problems and include difficulties with language or with identifying or recognizing things despite having no medical cause for these issues such as stroke or a brain tumor.

Depressive disorders involve feelings of sadness that interfere with the individual's ability to function or, as with adjustment disorder, persist longer than most people experience in reaction to a particular life stressor. Examples of depressive disorders include the following:

  • Major depression involves the sufferer feeling depressed most days and for most of each day for at least two weeks in a row. Along with sadness, the individual with major depression experiences a number of other associated symptoms, like irritability, loss of motivation or interest in activities they usually enjoy, hopelessness, and increased or decreased sleep, appetite, and/or weight. The person might also exhibit thoughts, plans, or attempts to harm themselves. Women with postpartum depression tend to experience many of the above symptoms for weeks to months after giving birth.
  • Dysthymia sufferers experience depression and milder levels of the symptoms of major depression. In dysthymia, the symptoms are fairly consistent for more than two years in adults and one year in children and adolescents.
  • Bipolar disorder, also called manic depression, is a mental illness that is characterized by severe mood swings, repeated episodes of depression, and at least one episode of mania in the person's lifetime. Bipolar disorder is one kind of mood disorder that afflicts more than 1% of adults in the United States, up to as many as 4 million people.

Substance use disorders, like substance abuse and substance dependence, involve the use of a substance that interferes with the social, emotional, physical, educational, or vocational functioning of the person using it. These disorders afflict millions of people and a variety of legal (for example, alcohol and inhalants like household cleaners) and/or illegal (for example, marijuana in most states, cocaine, Ecstasy, and opiates) substances may be involved.

Developmental disorders, like a learning disability, Asperger's disorder, or mental retardation, are often included in diagnostic manuals for mental disorders, but this group of conditions does not by definition mean the person involved has a problem with their mood.

It is important to understand that the list of conditions above is by no means exhaustive. This article focuses on the more common mental illnesses; illnesses like eating disorders and schizophrenia, that are less common but perhaps quite devastating to the life of the person with the condition, are omitted.

What are the causes and risk factors for mental illness?

One frequently asked question about mental illness is if it is hereditary. Most mental disorders are not directly passed from one generation to another genetically, and there is no single cause for mental illness. Rather, it is the result of a complex group of genetic, psychological, and environmental factors. Genetically, it seems that more often than not, there seems to be a genetic predisposition to developing a mental illness. Everything from mood, behavioral, developmental, and thought disorders are thought to have a genetic risk for developing the condition.

Medical conditions may predispose an individual to developing a mental illness. For example, depression is more likely to occur with certain medical illnesses. These "co-occurring" conditions include heart disease, stroke, diabetes, cancer, hormonal disorders (especially perimenopause or hypothyroidism, known as "low thyroid"), Parkinson's disease, and Alzheimer's disease. While it does not appear that allergies cause depression or vice versa, people who suffer from nonfood allergies have been found to be somewhat more vulnerable to also having depression compared to people who do not have allergies. Some medications used for long periods, such as prednisone, certain blood pressure medicines, sleeping pills, antibiotics, and even birth control pills, in some cases, can cause depression or make an existing depression worse. Some antiseizure medications, like lamotrigine (Lamictal), topiramate (Topamax), and gabapentin (Neurontin), may be associated with a higher risk of suicide. Despite the impact that taking certain medications or having a medical illness can have on a person's emotional state, clinical depression should not be considered a normal or natural reaction to either issue. It should therefore always be aggressively treated.

Environmentally, the risks of developing mental illness can even occur before birth. For example, the risk of schizophrenia is increased in individuals whose mother had one of certain infections during pregnancy. Difficult life circumstances during childhood, like the early loss of a parent, poverty, bullying, witnessing parental violence; being the victim of emotional, sexual, or physical abuse or of physical or emotional neglect; and insecure attachment have all been associated with the development of schizophrenia as well. Even factors like how well represented an ethnic group is in a neighborhood can be a risk or protective factor for developing a mental illness. For example, some research indicates that ethnic minorities may be more at risk for developing mental disorders if there are fewer members of the ethnic group to which the individual belongs in their neighborhood.

Stress has been found to be a significant contributor to the development of most mental illnesses, including bipolar disorder. For example, gay, lesbian, and bisexual people are thought to experience increased emotional struggles associated with the multiple social stressors associated with coping with reactions to their homosexuality or bisexuality in society. Unemployment significantly increases the odds ratio of an individual developing a psychiatric disorder. It almost quadruples the odds of developing drug dependence and triples the odds of having a phobia or a psychotic illness like schizophrenia. Being unemployed more than doubles the chances of experiencing depression, generalized anxiety disorder (GAD), and obsessive-compulsive disorder.


Depression Therapy: Myths, Facts, and More in Pictures See Slideshow

What are symptoms and signs of mental illness?

While everyone experiences sadness, anxiety, irritability, and moodiness at times, moods, thoughts, behaviors, or use of substances that interfere with a person's ability to function well physically, socially, at work, school, or home are characteristics of mental illness. Mental illness can have virtually any physical symptom associated with it, from insomnia, headaches, stomach upset to even paralysis. Socially, the person with a mental illness may avoid or have trouble making or keeping friends. Emotional problems can result in the person being unable to focus and therefore perform at work or school.

How do medical professionals diagnose mental illness?

There is no one test that definitively indicates that someone has a mental illness. Therefore, health-care practitioners diagnose a mental disorder by gathering comprehensive medical, family, and mental-health information. Patients tend to benefit when the professional takes into account their client's entire life and background. This includes but is not limited to the person's gender, sexual orientation, cultural, religious and ethnic background, and socioeconomic status. The symptom sufferer might be asked to fill out a self-test that the professional will review if the person being evaluated is able to complete it. The practitioner will also either perform a physical examination or request that the individual's primary-care doctor or other medical professional perform one. The medical examination will usually include lab tests to evaluate the person's general health and to explore whether or not the individual has a medical condition that might produce psychological symptoms.

In asking questions about mental-health symptoms, the counselor or other mental-health professional often explores if the individual suffers from hallucinations or delusions, depression and/or manic symptoms, anxiety, substance abuse, as well as some personality disorders (for example, schizotypal personality disorder) and developmental disorders (for example, autism spectrum disorders). Since some of the symptoms of any one mental disorder can also occur in other mental illnesses, the mental-health screening is to determine if the individual suffers from a psychotic depressive, bipolar, anxiety, behavioral, substance abuse, or personality disorder.

In addition to providing treatment that is appropriate to the diagnosis, determining the presence of mental illnesses that may co-occur (be comorbid) and addressing those issues is important when trying to improve the life of individuals with a mental illness. For example, people with schizophrenia are at increased risk of having a substance abuse, depressive, or anxiety disorder and of committing suicide.

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What is the treatment for a mental health problem?


Talk therapy (psychotherapy) is usually considered the first line of care in helping a person with a mental illness. It is an important part of helping individuals with a mental disorder achieve the highest level of functioning possible. These interventions are therefore seen by some as being forms of occupational therapy for people with mental illness. While medication can be quite helpful in alleviating and preventing overt symptoms for many psychiatric conditions, they do not address the many complex social and psychological issues that can play a major role in how the person with such a disease functions at work, at home, and in his or her relationships. For example, since about 60% of people with bipolar disorder take less than 30% of their medications as prescribed, any support that can promote compliance with treatment and otherwise promote the health of individuals in the mentally disordered population is valuable.

Psychotherapies that have been found to be effective in treating many mental disorders include family focused therapy, psycho-education, cognitive therapy, interpersonal therapy, and social rhythm therapy. Family focused therapy involves education of family members about the disorder and how to help (psycho-education), communication-enhancement training, and teaching family members problem-solving skills training. Psycho-education services involve teaching the person with the illness and their family members about the symptoms of the sufferer, as well as any warning signs (for example, change in sleep pattern or appetite, increased irritability) that the person is beginning to experience another episode of the illness, when applicable. In cognitive behavioral therapy, the mental-health professional works to help the person with a psychiatric condition identify, challenge, and decrease negative thinking and otherwise dysfunctional belief systems. The goal of interpersonal therapy tends to be identifying and managing problems the sufferers of a mental illness may have in their relationships with others. Social rhythm therapy encourages stability of sleep-wake cycles, with the goal of preventing or alleviating the sleep disturbances that may be associated with a psychiatric disorder.


Medications may play an important role in the treatment of a mental illness, particularly when the symptoms are severe or do not adequately respond to psychotherapy. For example, treatment of bipolar disorder with medications tends to address two aspects: relieving already existing symptoms of mania or depression and preventing symptoms from returning. Medications that are thought to be particularly effective in treating manic and mixed symptoms include olanzapine (Zyprexa), risperidone (Risperdal), quetiapine (Seroquel), ziprasidone (Geodon), aripiprazole (Abilify), paliperidone (Invega), and asenapine (Saphis). These medications belong to a group of medications called neuroleptics and are known for having the ability to work quickly compared to many other psychiatric medications. As a group of medications, side effects that occur most often include sleepiness, dizziness, and increased appetite. Weight gain, which may be associated with higher blood sugar, higher lipid levels, and sometimes increased levels of a hormone called prolactin may also occur. Although older medications in this class that were not mentioned here are more likely to cause muscle stiffness, shakiness, and very rarely uncoordinated muscle twitches (tardive dyskinesia) that can be permanent, health-care practitioners appropriately monitor the people they treat for these potential side effects as well. Mood-stabilizer medications like lithium, divalproex (Depakote), carbamazepine (Tegretol), and lamotrigine (Lamictal) can be useful in treating active (acute) symptoms of manic or mixed episodes. These medications may take a bit longer to work compared to the neuroleptic medications, and some (for example, lithium, divalproex, and carbamazepine) require monitoring of medication blood levels. Further, some of these medications can be associated with birth defects when taken by pregnant women.

Antidepressant medications are the primary medical treatment for the anxiety characterized by anxiety disorders, as well as the depressive symptoms of depressive disorders and bipolar disorder. Examples of those medications that are commonly prescribed for those purposes include serotonergic (SSRI) medications like fluoxetine (Prozac), sertraline (Zoloft), paroxetine (Paxil), citalopram (Celexa), and escitalopram (Lexapro) and combination serotonergic/adrenergic medications (SNRIs) like venlafaxine (Effexor) and duloxetine (Cymbalta), as well as bupropion (Wellbutrin), which is a dopaminergic antidepressant.

Medications like clonazepam (Klonopin) and lorazepam (Ativan) from the benzodiazepine group are often used to treat anxiety, particularly when it is sudden and severe, as in panic attacks. This class of medications does have addictive properties. Medications from the beta-blocker family (for example, propranolol [Inderal]) are sometimes used to treat the physical symptoms associated with anxiety as well.

Alzheimer's and other forms of dementia are often treated with medications like memantine (Namenda), galantamine (Razadyne), donepezil (Aricept), rivastigmine (Exelon), and tacrine (Cognex). These medications tend to slow the progression of dementia, thereby helping sufferers of dementia remain functional longer than they would without treatment.

Despite its stigmatized history, electroconvulsive therapy (ECT) can be a viable treatment for people whose symptoms of depression, bipolar, or thought disorder have inadequately responded to psychotherapies and a number of medication trials. Although alternative treatments for mood disorders like St. John's wort or ginkgo biloba are not recognized standard care for bipolar disorder, as many as one-third of some patients being treated for a mental illness use them.

Is it possible to prevent mental health disorders?

A variety of factors can contribute to the prevention of mental-health disorders. For example, people who feel less isolated and alone tend to be less likely to develop a mental-health disorder. Those who engage in regular practice of endurance exercise seem to have a more favorable self-image, more resistance to drug and alcohol addiction, and a higher sense of general physical and psychological well-being compared to those who do not exercise regularly. Adolescents who engage regularly in physical activity are characterized by lower levels of anxiety and depression compared to their more sedentary counterparts.

Clear communication by parents about the negative effects of alcohol, as well as about their expectations regarding drug use, has been found to significantly decrease alcohol and other drug use in teens. Adequate parental supervision has also been found to be a deterrent to substance use in children and adolescents. Alcohol and other drug use has been found to occur most often between the hours of 3 p.m. and 6 p.m., immediately after school and prior to parents' arrival home from work. Teen participation in extracurricular activities has therefore been revealed to be an important measure in preventing use of alcohol in this age group. Parents can also help educate teens about appropriate coping and stress-management strategies. For example, 15- to 16-year-olds who use religion to cope with stress tend to use drugs significantly less often and have less problems as a result of drinking than their peers who do not use religion to cope.

What is the prognosis for mental health problems?

Individuals with mental illness are at risk for a variety of challenges. For example, children who have either a father or mother who have been psychiatrically hospitalized seem to be at higher risk of dying from sudden infant death syndrome (SIDS). Depression in adults can lead to a significantly greater likelihood of health risk factors such as a lack of physical activity, smoking, binge drinking, obesity, high blood pressure, high cholesterol, and poor health. Fortunately, treatment for mental illness can go a long way to restoring the emotional and behavioral health of individuals with mental illness.

Where can people get support for mental health disorders?

National Alliance on Mental Illness (NAMI)

3803 N. Fairfax Dr., Ste. 100
Arlington, VA 22203
Main: 703-524-7600
Fax: 703-524-9094
Member services: 888-999-NAMI (6264)

National Depression and Bipolar Support Alliance (DBSA)
730 N. Franklin Street, Suite 501
Chicago, Illinois 60654-7225 USA
Toll-free phone: 800-826-3632
Fax: 312-642-7243

National Foundation for Depressive Illness, Inc.
PO Box 2257
New York, NY 10116

Mental Health America
2000 N. Beauregard Street, 6th Floor
Alexandria, VA 22311
Phone: 703-684-7722
Toll-free phone: 800-969-6642
Fax: 703-684-5968

Where can people get more information about mental illnesses?

National Institute of Mental Health
9000 Rockville Pike
Bethesda, Maryland 20892
[email protected]

Substance Abuse and Mental Health Services Administration (SAMHSA)
SAMHSA's Health Information Network
PO Box 2345
Rockville, MD 20847-2345
Phone: 877-SAMHSA-7 (877-726-4727)
[email protected]

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Medically Reviewed on 3/31/2021
Medically reviewed by Marina Katz, MD; American Board of Psychiatry & Neurology


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