Mental health is all about how people think, feel, and behave. Mental health specialists can help people with depression, anxiety, bipolar disorder, addiction, and other conditions that affect their thoughts, feelings, and behaviors.
Mental health can affect daily living, relationships, and physical health.
However, this link also works in the other direction. Factors in people’s lives, interpersonal connections, and physical factors can contribute to mental ill health.
Looking after mental health can preserve a person’s ability to enjoy life. Doing this involves balancing life activities, responsibilities, and efforts to achieve psychological resilience.
Stress, depression, and anxiety can all affect mental health and disrupt a person’s routine.
Although health professionals often use the term mental health, doctors recognize that many psychological disorders have physical roots.
This article explains what people mean by mental health and mental illness. We also describe the most common types of mental disorders, including their early signs and how to treat them.
What is mental health?

According to the World Health Organization (WHO)Trusted Source:
“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 just the absence of mental disorders or disabilities.” Peak mental health is not only about managing active conditions but also looking after ongoing wellness and happiness.
It also emphasizes that preserving and restoring mental health is crucial individually and at a community and society level.
In the United States, the National Alliance on Mental Illness estimates that almost 1 in 5 adults experience mental health problems each year.
In 2020, an estimated 14.2 million adultsTrusted Source in the U.S., or about 5.6%, had a serious psychological condition, according to the National Institute of Mental Health (NIMH).
Risk factors for mental health conditions
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, mental disorders are one of the leading causes of disability.
Social and financial circumstances, adverse childhood experiences, biological factors, and underlying medical conditions can all shape a person’s mental health.
Many people with a mental health disorder have more than one condition at a time.
It is important to note that good mental health depends on a delicate balance of factors and that several elements may contribute to developing these disorders.
The following factors can contribute to mental health disruptions.
Continuous social and economic pressure
Having limited financial means or belonging to a marginalized or persecuted ethnic group can increase the risk of mental health disorders.
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 affect the availability and quality of mental health treatment for certain groups.
Modifiable factors for mental health disorders include:
- socioeconomic conditions, such as whether work is available in the local area
- occupation
- a person’s level of social involvement
- education
- housing quality
- gender
Nonmodifiable factors include:
- gender
- age
- ethnicity
- nationality
The researchers found that being female increased the risk of low mental health status by nearly 4 times. People with a “weak economic status” also scored highest for mental health conditions in this study.
Childhood adversity
Several studiesTrusted Source support that adverse childhood experiences such as child abuse, parental loss, parental separation, and parental illness significantly affect a growing child’s mental and physical health.
There are also associations between childhood abuse and other adverse events with various psychotic disorders. These experiences also make people vulnerable to post-traumatic stress disorder (PTSD).
Biological factors
The NIMH suggests that genetic family history can increase the likelihoodTrusted Source of mental health conditions as specific genes and gene variants put a person at higher risk.
However, many other factors contribute to the development of these disorders.
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 illness can still have mental health issues.
Chronic stress and mental health conditions such as depression and anxiety may develop due to underlying physical health problems, such as cancer, diabetes, and chronic pain.
Types of mental health disorders
Specific mental disorders are grouped together due to features they have in common. Some types of mental illness are as follows:
- anxiety disorders
- mood disorders
- schizophrenia disorders
Anxiety disorders
According to the Anxiety and Depression Association of America, anxiety disorders are the most common mental illness.
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:
- restlessness
- fatigue
- poor concentration
- tense muscles
- interrupted sleep
A bout of anxiety symptoms does not necessarily need 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 a panic disorder experience regular panic attacks involving sudden, overwhelming terror or a sense of imminent disaster and death.
Read more about panic attacks here.
Phobias
There are different types of phobia:
- 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 subject to the judgment of others. People with social phobia often restrict their exposure to social environments.
- Agoraphobia: This term refers to a fear of situations where getting away may be difficult, such as being in an elevator or a moving train. Many people misunderstand this phobia as the fear of being outside.
Phobias are deeply personal, and doctors do not know every type. There could be thousands of phobias, and what may seem unusual to one person can be a severe problem that dominates daily life for another.
OCD
People with obsessive-compulsive disorder (OCD) have obsessions and compulsions. In other words, they experience constant, stressful thoughts and a powerful urge to perform repetitive acts, such as handwashing.
PTSD
PTSD can occur after a person experiences or witnesses an intensely stressful or traumatic event. During this type of event, the person thinks that 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.