The 5 Most Common Mental Illnesses


The root cause of many forms of mental illness is as yet strongly debated. However, science and medicine have been able to pinpoint their symptoms and developed effective therapy and treatment regimens. Here are the 5 most frequently-appearing mental illnesses in the world today.

1. Anxiety Disorders

In the U.S., anxiety disorders are one of the most common mental illnesses. It afflicts 40 million adult Americans aged 18 and over, or 18.1% of the total population. Meanwhile, an estimated 284 million people suffer from anxiety globally. Anxiety disorders can result from a variety of factors like genetic predisposition, brain chemistry, and traumatic life events. Anxiety is a highly treatable illness, and a form of anxiety known as General Anxiety Disorder (GAD) may afflict even more people than currently recorded, as it is estimated that over 75% who have the disorder don’t seek treatment. Psychotherapy and medication can help manage this condition and in Florida there are many facilities for anxiety disorder treatment.

2. Depression

The World Health Organization counts depression as the most common mental illness worldwide. According to the WHO, the number of anxiety-afflicted individuals is at 300 million. While there is no proof that hormones play a role in depression, it has been found that depression afflicts women more often than men. Depression entails feelings of guilt or low self-esteem, loss of interest or pleasure, a general feeling of sadness, sleeplessness, exhaustion, or a lack of concentration. A person can develop depression due to genetics, medical problems, medication, and traumatic life events. Since it can be recurring or long-lasting, depression can severely impair a person’s ability to function at school or work, and can impact their relationships. Severe depression can prompt suicidal thoughts and the desire to act on them. Antidepressant medication combined with cognitive-behavioral therapy and psychotherapy can effectively treat depression.

woman with dementia

3. Dementia

This mental illness is the progressive degeneration of a person’s cognitive function. Dementia can affect memory, comprehension, calculation, and language ability, along with a deterioration of emotional and social control. Dementia can be caused by many diseases that affect the brain, and there is no cure. However, there are palliative treatments that can ease the confusion and distress of the patient.

4. Bipolar Affective Disorder

This mental illness is characterized by manic and depressive episodes. Bipolar disorder afflicts as many as 60 million people globally, and seems to be more prevalent in countries where people have higher incomes. While its cause isn’t entirely known, bipolar disorder can arise from a mix of genetic, environmental, and neurochemical factors. Psychosocial support and medication are effective in treating this disorder.

5. Schizophrenia and Psychosis

Different types of psychoses and schizophrenia are mental illnesses that affect 23 million people globally. Schizophrenia is described as an illness that includes distortions in perception, thinking, emotions, behavior, and sense of self. Schizophrenics experience delusions and hallucinations in late adolescence or early adulthood, making it difficult for them to work, study, or interact socially. Psychotherapy, psychosocial therapy, and medication can treat this condition.

Mental illnesses affects nearly every person on the planet in some way, and these are only a few of the commonly documented disorders. Taking the time to recognize symptoms—whether in yourself, your friends or relatives, and getting an accurate diagnosis can help find the most appropriate treatment from a licensed professional.

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