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types of mental health disorders

6 Types of Mental Health Disorders

There are several common types of mental health disorders. It’s estimated that about one in five adults in the US experienced the symptoms of a mental health disorder in 2020, and about one in 20 adults struggles with serious mental health issues. 

Statistically, we all know at least one person who has had a brush with depression, anxiety, or another mental health issue, and awareness of the prevalence and severity of mental health problems is, thankfully, higher than ever. 

In this article, we’re exploring several common types of mental health disorders.

Types of Mental Health Disorders

Access to mental healthcare is still greatly limited, and less than 40 percent of those who need it, get it. The modern public outlook on therapy is still outdated, giving many the impression that it is ineffective or unnecessary. And more systemically, therapy remains costly and financially inaccessible to those who need it the most. 

Supporting ourselves and our loved ones is central to long-term mental health management. A big part of that includes understanding how mental health disorders can affect people, change their lives, and respond to different kinds of treatment. 

Mental health issues vary greatly in type and severity, but most of the common mental health disorders we face today can be distinguished between the following types.  

Here are six common types of mental health disorders.

Anxiety Disorders

Anxiety disorders encompass the most common mental health disorders known throughout the world. While most people are familiar with concepts like social anxiety and stage fright, anxiety disorders also encompass generalized anxiety, agoraphobia, panic disorder, and stress- or trauma-related conditions like post-traumatic stress disorder. 

Worry and nervousness are normal elements of the human condition, but a person struggling with an anxiety disorder experiences an inordinate amount of fear and alarm even under calm circumstances. They will fixate and remember worries without any apparent triggers and can experience powerful intrusive thoughts, ones that often influence behavior as well. 

While anxiety disorders encompass a wide range of different mental health disorders, it is very important not to conflate one for another or generalize all anxiety disorders as being the same. 

There are very distinct differences between being diagnosed with generalized anxiety and a phobia, or with panic disorder and post-traumatic stress. The risk factors and causes for these disorders differ greatly, as do their treatments. A few common anxiety disorders include: 

  • Generalized anxiety disorder
  • Social anxiety disorder
  • Panic disorder
  • Post-traumatic stress disorder
  • Separation anxiety disorder
  • Selective mutism
  • Phobias
  • And more

Mood Disorders

Mood disorders are the second most common type of mental health disorder in the world. They include unipolar depression and bipolar disorder and encompass a variety of different conditions characterized by excessively low or high mood.

The two dichotomous symptoms of a mood disorder are depression and mania. Depression describes long periods of sadness and anhedonia, accompanied by mental and physical fatigue, as well as physical symptoms such as unexplained aches and pains. Mania describes a dangerous sense of grandeur, accompanied by bursts of energy and restlessness. 

Some mood disorders are caused by physical conditions, medication, or substance use, while others can be

Most mood disorders involve depression, the most common being major depressive disorder. Bipolar disorder, formerly known as manic depression, is commonly diagnosed in patients who experience two or more alternating periods of hypomania, mania, or depression (each period lasting months, usually). Different mood disorders include: 

  • Major depressive disorder
  • Seasonal affective disorder
  • Premenstrual dysphoric disorder
  • Bipolar disorder
  • Cyclothymic disorder
  • And more

Obsessive-Compulsive Disorder

Previously considered an anxiety disorder, an obsessive-compulsive disorder has now been given its own category. 

There are two elements to an obsessive-compulsive disorder: the intrusive and unwanted obsessive thought, and the compulsive behavior used to soothe that thought. This creates the cycle that fuels OCD, creating a loop of repeating intrusive thoughts and compulsive behavior. 

When a person washes their hands fifteen times or locks and unlocks every door in the house multiple times per day, they’re engaging in a ritual that helps them ease an irrational yet deep-seated worry that they cannot get rid of on their own. OCD can take on many different forms, but some of the most common unwanted thoughts and fears include: 

  • Fear of contamination and contact with germs, vermin, animals, and bodily fluids
  • Fear of losing control or doing something irrational
  • Fear of accidentally hurting others
  • Unwanted thoughts
  • Worrying about not being moral enough
  • Fear of losing objects or forgetting important things
  • Worrying about symmetry and evenness in the world around you
  • Inability to make decisions
  • Hoarding things in a fear of throwing them away

Common rituals associated with OCD include: 

  • Excessive cleaning or washing
  • Arranging by size, number, or other physical characteristics
  • Counting or muttering words or phrases
  • Seeking reassurance from others constantly
  • Doing things in specific multiples
  • Repeating a set routine multiple times
  • Repeatedly checking the “state” of something (locked and unlocked doors, open and closed windows, lights that are on or off)


Schizophrenia is one of the most misunderstood mental health disorders affecting people today. While sometimes conflated with dissociative identity disorder, schizophrenia is characterized by serious alterations in perception, mood, thoughts, and behavior. 

A person with schizophrenia is increasingly removed from reality and will become more outwardly distant and isolated while experiencing strong delusions and hallucinations. It is a lifelong condition, requiring treatment to control and reduce symptoms and allow for a normal quality of life. If left untreated, schizophrenia can be disabling. Schizophrenia affects over 20 million people across the globe. 

Personality Disorders

There are ten different recognized personality disorders split between three clusters or types. Personality disorders are often long-term conditions that are diagnosed in teenage or early adult years. 

The three main clusters of personality disorders are the eccentric cluster (Cluster A), the dramatic cluster (Cluster B), and the anxious cluster (Cluster C). In total, all ten personality disorders include: 

  • Cluster A
    • Paranoid Personality Disorder
    • Schizoid Personality Disorder
    • Schizotypal Personality Disorder
  • Cluster B
    • Antisocial Personality Disorder 
    • Borderline Personality Disorder
    • Histrionic Personality Disorder
    • Narcissistic Personality Disorder
  • Cluster C
    • Avoidant Personality Disorder
    • Dependent Personality Disorder
    • Obsessive-Compulsive Personality Disorder

Attention Deficit Hyperactivity Disorder

Attention deficit hyperactivity disorder is often diagnosed in children and adolescents but can persist into adulthood. ADHD is known as a neurodevelopmental disorder and is characterized by difficulty paying attention, impulsive behavior, and hyperactivity. 

While children aren’t always known for having long attention spans, a child, teen, or adult struggling with ADHD will have a much harder time than normal focusing on a single thing and will often seek out something else to do or fixate on. 

People with ADHD struggle to concentrate at school or work, have a harder time with executive functioning (decision-making, self-control, and day planning), and struggle with delayed gratification and long-term goals. 

Medication is an important part of treating ADHD. Alongside therapy, ADHD symptoms can be massively reduced, even at a young age, helping reduce the risk of substance use and poor outcomes at a later age. 

There are other common mental health issues affecting millions of people in the US, including eating disorders and substance use disorders. Mental health disorders can be just as challenging and debilitating as chronic physical health issues. Seeking appropriate medical help as soon as possible is important – as is educating yourself and learning more about your loved one’s condition. 

If you worry that you or someone you know may be struggling with a mental health issue, be sure to get in touch with a mental health professional and schedule an appointment together.

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