Mental health is about how people think, feel, and behave. Mental health care professionals can help people manage conditions such as depression, anxiety, bipolar disorder, addiction, and other disorders that affect their thoughts, feelings, and behaviors.

Mental health can affect a person’s day-to-day life, relationships, and physical health. External factors in people’s lives and relationships can also contribute to their mental well-being.

Looking after one’s mental health can help a person maintain their ability to enjoy life. This involves balancing their activities, responsibilities, and efforts to achieve psychological resilience.

Stress, depression, and anxiety can affect mental health and may disrupt a person’s routine.

Although healthcare professionals often use the term “mental health,” doctors recognize that many mental health conditions have physical roots.

This article explains what mental health and mental health conditions mean. It also describes the most common types of mental health disorders, including their early signs and how to treat them.

“Mental health is a state of mental well-being that enables people to cope with the stresses of life, realize their abilities, learn well and work well, and contribute to their community.”

The WHO states that mental health is “more than the absence of mental disorders.” Peak mental health is about managing active conditions and maintaining wellness and happiness.

The organization also emphasizes that preserving and restoring mental health is important at individual, community, and societal levels.

In the United States, the National Alliance on Mental Illness estimates that almost 1 in 5 adults experience mental health problems each year.

In 2021, an estimated 14.1 million adultsTrusted Source in the U.S., about 5.5% of the adult population, had a serious psychological condition, according to the National Institute of Mental Health (NIMH).

Everyone is at some risk of developing a mental health disorder, regardless of age, sex, income, or ethnicity. In the U.S. and much of the developed world, depression is one of the leading causesTrusted Source of disability.

Social and financial circumstances, adverse childhood experiences, biological factors, and underlying medical conditions can allTrusted Source shape a person’s mental well-being.

Many people with a mental health disorder have more than oneTrusted Source condition at the same time.

It is important to note that mental well-being depends on a balance of factors, and several elements may contribute to the development of a mental health disorder.

The following factors can contribute to mental health conditions.

Socioeconomic pressure

Having limited financial means or belonging to a marginalized ethnic group can increase the risk of mental health disorders as a result of biases in healthcare.

A 2015 Iranian studyTrusted Source describes several socioeconomic causes of mental health conditions, including poverty and living on the outskirts of a large city.

The researchers also described flexible (modifiable) and inflexible (nonmodifiable) factors that can affect the availability and quality of mental health care treatment for certain groups.

Modifiable factors for mental health disorders include:

  • socioeconomic conditions, such as whether work is available in a local area
  • occupation
  • a person’s level of social involvement
  • education
  • housing quality

Nonmodifiable factors include:

  • gender
  • age
  • ethnicity
  • nationality

The researchers found that being female increased the risk of low mental health status by nearly four times. People with a “weak economic status” scored highest for mental health conditions in this study.

Childhood adversity

Several studiesTrusted Source report that childhood traumas such as child abuse, parental loss, parental separation, and parental illness significantly affect a growing child’s mental and physical health.

There are associations between childhood abuse and other adverse events and mental health disorders. These experiences also make people vulnerable to post-traumatic stress disorder (PTSD).

Biological factors

The NIMH suggests that a person’s family history can increase the likelihoodTrusted Source of mental health conditions, as specific genes and gene variants put a person at higher risk. However, having a gene associated with a mental health disorder does not guarantee that a condition will develop.

Likewise, people without related genes or a family history of mental health conditions may have a mental health disorder.

Chronic stress and mental health disorders such as depression and anxiety may develop due to underlying physical health problems, such as cancer, diabetes, and chronic pain.

Mental health resources

Visit our dedicated hub for more research-backed information and resources on mental health and well-being.

Healthcare professionals group mental health disorders according to the features they have in common. They include:

Anxiety disorders

According to the Anxiety and Depression Association of America, anxiety disorders are the most common mental health disorders.

People with these conditions have severe fear or anxiety related to certain objects or situations. Most people with an anxiety disorder try to avoid exposure to whatever triggers their anxiety.

Below are some examples of anxiety disorders.

Generalized anxiety disorder

Generalized anxiety disorder (GAD) involves excessive worry or fear that disrupts everyday living.

People may also experience physical symptoms, including:

Anxiety symptoms do not always have a specific trigger in people with GAD.

They may experience excessive anxiety when encountering everyday situations that do not pose a direct danger, such as chores or appointments. A person with GAD may sometimes feel anxiety with no trigger at all.

Panic disorder

People with panic disorder experience regular panic attacks involving sudden, overwhelming terror or a sense of imminent disaster and death.

Phobias

There are many types of phobias, and what may seem typical to one person might be a severe problem that dominates daily life for another. Different types include:

  • Simple phobias: These may involve a disproportionate fear of specific objects, scenarios, or animals. A fear of spiders is a typical example.
  • Social phobia: Sometimes known as social anxiety, this is a fear of being watched or judged by others. People with social phobia often restrict their exposure to social environments.
  • Agoraphobia: The term “agoraphobia” refers to a fear of situations where getting away may be difficult, such as being in an elevator or a moving train. People sometimes misunderstand this phobia as a fear of being outside.

Obsessive-compulsive disorder

People with obsessive-compulsive disorder (OCD) may experience constant, stressful thoughts and an urge to perform repetitive acts, such as handwashing.

PTSD

PTSD can occur after a person experiences or witnesses a stressful or traumatic event. During this type of event, the person thinks their life or other people’s lives are in danger. They may feel afraid or that they have no control over what is happening.

These sensations of trauma and fear may then contribute to PTSD.

Mood disorders

People may also refer to mood disorders as affective disorders or depressive disorders.

People with these conditions have significant mood changes, generally involving either mania, a period of high energy and joy, or depression. Examples of mood disorders include:

  • Major depression: An individual with major depression experiences a constant low mood and loses interest in activities and events that they previously enjoyed (anhedonia). They may feel prolonged periods of sadness or extreme sadness.
  • Bipolar disorder: A person with bipolar disorder experiences unusual changesTrusted Source in their mood, energy levels, levels of activity, and ability to continue with daily life. Periods of high mood are known as manic phases, while depressive phases bring on low mood.
  • Seasonal affective disorder (SAD): Reduced daylight during the fall, winter, and early spring months triggers SAD, a type of major depressionTrusted Source. It is most common in countries far from the equator.

Schizophrenia disorders

The term “schizophrenia” often refers to a spectrum of disorders characterized by features of psychosis and other severe symptoms. These are highly complex conditions.

According to the NIMH, signs of schizophrenia typically develop between the ages of 16 and 30Trusted Source. A person will have thoughts that appear fragmented, and may also find it hard to process information.

Schizophrenia has negative and positive symptoms. Positive symptoms include delusions, thought disorders, and hallucinations, while withdrawal, lack of motivation, and a flat or inappropriate mood are examples of negative symptoms.

Early signs

No physical test or scan reliably indicates whether a person has developed a mental health condition. However, people should look out for the following as possible signs:

  • withdrawing from friends, family, and colleagues
  • avoiding activities they would usually enjoy
  • sleeping too much or too little
  • eating too much or too little
  • feeling hopeless
  • having consistently low energy
  • using mood-altering substances, including alcohol and nicotine, more frequently
  • displaying negative emotions
  • being confused
  • being unable to complete daily tasks, such as getting to work or cooking a meal
  • having persistent thoughts or memories that reappear regularly
  • thinking of causing physical harm to themselves or others
  • hearing voices
  • experiencing delusions
Diagnosis

Diagnosing a mental health disorder requires a multistep process. A doctor may begin by looking at a person’s medical history and performing a thorough physical exam to rule out a physical condition that may be causing the symptoms. They may also order laboratory tests, such as imaging exams and bloodwork, to screen for possible underlying causes.

The healthcare professional will also do a psychological evaluation. This includes asking about a person’s symptoms and experiences and how these affect the individual’s life. The doctor may ask a person to complete mental health questionnaires to help understand their thoughts, feelings, and behavior patterns.