Depression is a serious medical disorder, but it’s not considered a disease. Here’s why.

Some people use the terms “disease“ and “disorder“ interchangeably. However, these terms have different definitions:

  • A disorder disrupts your typical physical or mental functioning, resulting in distress or difficulties in your daily life.
  • A disease is a type of sickness that involves a specific, distinct process in the body that is clearly defined.

When it comes to mental health, clinicians usually use the term “disorder“ rather than “disease.“

Depression is a common condition, so you’re not alone if you’re experiencing symptoms. Depression is highly treatable, and most people respond well to treatment.

The Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) categorizes depression under the class of depressive disorders.

Depression is also classed as a mental illness and a mental health condition, but not as a disease.


Disorders are often a collection of symptoms that come together to disrupt how your body or brain functions.

Other examples of disorders include epilepsy and type 1 diabetes. Epilepsy disrupts how your nervous system usually functions, and type 1 diabetes affects the body’s ability to regulate blood sugar levels.


A disease is a type of sickness that doctors can diagnose using medical testing. Diseases have an identifiable cause, such as infection, inflammation, or environmental factors.

Diseases cause a problem for a specific part of the body, like how cancer can grow in a particular location from a specific type of cell.

Diseases can be prevented with vaccines or treated with medical interventions, such as surgery or medication.

Depression isn‘t something you can catch from another person or see on a CT scan. It’s not a sickness in part of the body from infection. Although medication is a successful depression treatment, you can’t cure it with surgery or prevent it with a vaccine.

Diseases can be infectious and spread in various ways, like through air, water, or food. Examples of diseases include:

  • COVID-19
  • influenza
  • tuberculosis
  • hepatitis
  • typhoid
  • measles

Diseases can also be noncontagious, such as cancer, cataracts, and heart disease.

Depression is a disorder that interferes with your daily functioning. It can affect you both mentally and physically.

Most people have felt sad or unmotivated at some point in their lives. This doesn‘t necessarily mean they’re experiencing depression. But if the symptoms persist and interfere with your life, you might meet the criteria for a depressive disorder diagnosis.

There are several types of depression, including major depressive disorder, also known as clinical depression.

Depression isn‘t just an issue with emotions and feelings. It affects multiple areas of a person’s life, as described by the biopsychosocial model of health.

The biopsychosocial model acknowledges that when a person has a diagnosis, it can impact multiple areas of their life. Diagnoses are no longer viewed as isolated issues, but things that affect the whole person. This has led to a compassionate and empathetic approach in medicine.

This model was introduced in 1977 by American psychiatrist George Engel as a model for a holistic (whole person) approach to caring for patients.

Now, clinicians focus on the big picture. For example, they consider how a physical illness can impact a person’s state of mind and social experience. It’s more than just a medical issue.

The biopsychosocial model consists of three realms:

  • biological (physical)
  • psychological (thoughts, behaviors, and emotions)
  • social (cultural, socioenvironmental, and socioeconomic)

Depression is a mental, physical, and social issue, with causes and risk factors from all three areas.

Depression meets the criteria for a disorder because of the way it disrupts a person’s functioning in all three areas of the biopsychosocial model.


Depression can cause physical changes that result in multiple health issues.

For example, the increase in heart rate and blood pressure that can accompany depression can also reduce the blood flow to your heart. This, combined with a rise in the stress hormone cortisol, can lead to heart disease.

A 2014 study featuring 2,981 participants found a link between depression, anxiety, and physical pain, with cardiorespiratory pain (pain related to the heart and lungs) being the most reported type.

In addition to problems for your heart, depression can also cause:

  • inflammation
  • immune system changes
  • fatigue
  • appetite changes
  • weight fluctuations
  • increased pain sensitivity
  • headaches
  • body aches
  • digestive issues


It’s easy to connect a depression diagnosis and changes to a person’s psychology. This is another area where this disorder can disrupt daily life.

Depression can contribute to:

  • apathy
  • low self-esteem
  • hopelessness
  • sadness
  • grief
  • guilt
  • loss of interest in things that previously brought enjoyment
  • cognitive changes, like loss of concentration and difficulty making decisions


Feeling physically and psychologically unwell can impact your social connections. Depression can interfere with your social life in various ways, such as:

Each of these areas can affect each other. For example, social withdrawal can lead to hopelessness, resulting in appetite loss. This, in turn, can lead to weight loss, malnourishment, and more physical and cognitive changes.

These interactions can make untreated depression feel overwhelming. It’s not just you, though. Many people with depression feel this way.

That said, depression is very treatable. The American Psychiatric Association (APA) states that about 80% to 90% of people with depression respond to treatment. A combined approach of medication and therapy works well.

A disease is an illness with an identifiable cause that medical professionals can diagnose and treat. A disorder is a disruption in typical functioning.

The DMS-5 classifies depression as a disorder. It can disrupt a person’s physical, psychological, and social health.

Depression responds well to treatment, and there is a lot of support available.

The first step is visiting your doctor, who can refer you to a mental health professional. You can also search online to find a doctor in your area:

If you or someone you know is contemplating suicide, the National Suicide Prevention Lifeline is available 24/7 to offer free and confidential support at 800-273-8255.