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Mental Health Basics

What Is Mental Health?

Mental health refers to your emotional and psychological well-being. Having good mental health helps you lead a happy and healthy life. Your mental health can be influenced by a variety of factors, including life events or even your genetics.

There are many strategies that can help you establish and keep good mental health. These can include:

  • keeping a positive attitude
  • staying physically active
  • helping other people
  • getting enough sleep
  • eating a healthy diet
  • asking for professional help with your mental health if you need it
  • socializing with people whom you enjoy spending time with
  • forming and using effective coping skills to deal with your problems

What Is Mental Illness?

A mental illness is a condition that affects the way you feel and think. It can also affect your capacity to get through day-to-day life. Mental illnesses can be influenced by several different factors, including:

  • genetics
  • environment
  • daily habits
  • biology

Mental illnesses are common in the United States. About one in five American adults experience at least one mental illness each year, and about one in five young people ages 13 to 18 experience a mental illness at some point in their lives.

Mental illnesses are common, but they vary in severity. About one in 25 adults experience a serious mental illness (SMI) each year. An SMI can significantly reduce your ability to carry out daily life. Different groups of people experience SMIs at different rates.

According to the National Institute of Mental Health, women are more likely to experience SMI than men, people ages 26-49 are most likely to experience an SMI, and people with a mixed race background are more likely to experience an SMI than people of other ethnicities.

Each type of mental illness is associated with its own symptoms, but most share some common characteristics. Some common signs of mental illness may include:

  • not eating enough or overeating
  • having insomnia or sleeping too much
  • distancing yourself from other people and favorite activities
  • feeling fatigue even with enough sleep
  • feeling numbness or lacking empathy
  • experiencing unexplainable body pains or achiness
  • feeling hopeless, helpless or lost
  • smoking, drinking, or using illicit drugs more than ever before
  • feeling confusion, forgetfulness, irritability, anger, anxiety, sadness, or fright
  • constantly fighting or arguing with friends and family
  • having extreme mood swings that cause relationship problems
  • having constant flashbacks or thoughts that you can’t get out of your head
  • hearing voices in your head that you can’t stop
  • having thoughts of hurting yourself or other people
  • being unable to carry out day-to-day activities and chores

Mental Health Disorders

Mental health professionals use the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) to diagnose mental illnesses. There are many types of mental health disorders, with almost 300 different conditions listed in DSM-5. Below are some of the most common mental illnesses affecting people in the United States:

Bipolar Disorder

Bipolar disorder is a chronic mental illness that affects about 2.9 percent of Americans each year. It causes extreme mood swings, ranging from energetic, manic highs to depressive lows. These can affect your energy level and ability to think reasonably. These mood swings are much more severe than the small ups and downs most people experience on a daily basis.


Dysthymia, also called persistent depressive disorder, is a chronic type of depression. While dysthymic depression isn’t intense, it can interfere with your daily life. People with this condition experience symptoms for at least two years. It’s estimated that about 1.5 percent of American adults experience dysthymia each year.

Generalized Anxiety Disorder

Generalized anxiety disorder (GAD) is a chronic mental illness that causes you to become extremely worried about many things, even when there’s little or no reason to worry. Those with GAD feel very nervous about getting through the day and think things won’t ever work in their favor. Sometimes worrying can keep people with GAD from accomplishing everyday tasks and chores. GAD affects 3.1 percent of Americans every year.

Major Depression

Major depression, also called major depressive disorder (MDD), causes you to experience extreme sadness or hopelessness for at least two weeks. People with MDD may become so upset about their lives that they think about or try to commit suicide. About 7 percent of Americans experience at least one major depressive episode each year.

Obsessive-Compulsive Disorder

Obsessive-compulsive disorder (OCD) causes constant and repetitive thoughts, or obsessions. This occurs with unnecessary and unreasonable desires to carry out certain behaviors, or compulsions. Many people with OCD realize that their thoughts and actions are unreasonable, yet they cannot stop them. More than 2 percent of Americans are diagnosed with OCD at some point in their lifetime.

Post-Traumatic Stress Disorder (PTSD)

Post-traumatic stress disorder (PTSD) is a mental illness that causes people who have experienced traumatic events, such as war, natural disasters, or accidents, to experience ongoing psychological problems. Some of the symptoms include flashbacks to a traumatizing event or being easily startled. It’s estimated that 3.5 percent of the population in the United States experiences PTSD.


Schizophrenia is a chronic mental illness that impairs your ability to make choices and connect with other people. It’s a serious condition that can cause you to experience hallucinations, have delusions, and hear voices. It’s estimated that 1 percent of the population experiences schizophrenia.

Social Phobia

Social phobia, also called "social anxiety disorder," is a type of mental illness that causes you to develop an extreme fear of social situations. It can cause you to get very nervous about being around other people and you may have difficulty communicating with people because you think people will judge you. Approximately 15 million adults in the United States experience social phobia each year.

Coping with Mental Illnesses

The symptoms of many mental illnesses may get worse if they’re left untreated. Reach out for psychological help if you or someone you know may have a mental illness. Start by paying a visit to your primary care doctor. They can check for signs of mental illness and help establish a treatment plan if necessary.

Content licensed from:

Written by: Erica Cirino
Medically reviewed on: Mar 11, 2016: Timothy J. Legg, PhD, PMHNP-BC

This feature is for informational purposes only and should not be used to replace the care and information received from your health care provider. Please consult a health care professional with any health concerns you may have.
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