Experiencing depression, even in the casual sense of the word, can indicate a state of being unwell that qualifies as an illness.

The words “illness,” “disorder,” and “disease” are often used interchangeably in casual conversation, but they aren’t necessarily the same.

Historically, illness has been used to describe times when you feel unwell. It’s a term that captures both physical and psychological suffering. “I feel ill” is akin to saying “I feel sick.”

“Disorder” is the medical term for illnesses that impair important areas of physical and mental function. Disorders are often persistent, presenting long-term daily challenges to normal function.

Diseases can be the cause of disorders, but “disease” typically refers to a pathophysiological process happening in the body. Heart disease, for example, describes processes affecting blood flow to the heart.

Under these definitions, depression qualifies as both an illness and a disorder, and some research supports its inclusion as a disease, as well.

Yes. Depression is considered an illness and a disorder.

It’s listed as major depressive disorder (MDD) in the Diagnostic and Statistical Manual of Mental Disorder, 5th edition, text revision (DSM-5-TR), a clinical guidebook for diagnosing mental health conditions.

According to the DSM-5-TR, mental disorders are conditions where symptoms cause significant disruption to your cognition, emotional regulation, or behavior. These symptoms are usually associated with major distress and impairment in social, occupational, and other important areas of function.

Mental health disorders in the DSM-5-TR are experiences outside of cultural norms.

Whether or not depression can be classified as a disease remains a topic of debate.

As the understanding of the causes of depression and its biological underpinnings grows, more and more experts are championing its inclusion as a disease.

In a 2016 research article, the authors explain that depression not only has its own biological characteristics, but it may also contribute to other disease processes in the body, such as inflammation, platelet activity, and autonomic nervous system activity.

In this way, they argue, depression meets the definition of a systemic (whole-body) disease.

In many nonmedical settings, “depression” has become interchangeable with “sadness,” but depression isn’t an emotion.

Depression is a mental health disorder. It involves negative feelings like sadness, dismay, and despair, but it isn’t an emotion on its own.

The word “depressed” simply means downcast, lowered. It’s natural to have days where you feel down or to experience times of sadness and loss in life. During these times you may have a depressed mood, but not necessarily a diagnosable mental health condition.

Genetics may play a role in how likely you are to experience MDD, but no clear link shows genetics cause depression.

How the two are related appears to be complex. Research is ongoing to investigate if genetics cause depression, influence its progression, or can be linked to specific variants of the disorder.

A 2018 review, for example, found genetics made only a small contribution to the progression of depression, likely through secondary mechanisms like cytokine production and disruption of neurogenesis, the production of new neurons in the brain.

A study done in 2022 using data from more than 500,000 people found genetics may significantly influence the development of early-age onset depression.

Yes. Depression can be classified as a disability if it prevents you from engaging in activities or interacting with the world around you.

The Centers for Disease Control (CDC) indicate disabilities can be conditions of the body or mind that cause:

  • physical or mental impairment
  • activity limitation
  • participation restriction

Some of the hallmark symptoms of depression involve disability. Cognitive impairment, chronic fatigue, and loss of interest in self-motivated activities are all ways that depression can limit your ability to engage with the world around you.

Major depressive disorder is listed in the Americans with Disabilities Act (ADA) as a disability that may entitle you to workplace accommodations.

Although the ADA doesn’t keep a complete list of conditions that potentially qualify as disabilities, its Psychiatric Enforcement Guidance document names MDD and other disorders that include features of depression, such as bipolar disorder.

Learn more about applying for disability with depression here.

There’s no cure for depression, but that doesn’t mean you’re going to experience symptoms for your entire life. There are many treatments and therapies designed to reduce your symptoms and improve your mental health.

In order for depression to have a cure, you’d have to be able to say with complete certainty that symptoms will never return after they go away.

Depression has no clear pathology, and that makes it impossible to say if an underlying cause has been completely resolved.

What we do know is that clinical samples show 75% of people living with depression will experience multiple episodes.

Analysis data from 2011, still used in current research models, indicates there is a 60% chance of MDD recurrence after your first episode. With every additional episode, your chance of recurrence goes up.

That still means many people never have more than one episode of major depression. Just because symptoms go away, however, doesn’t mean the condition is definitively cured.

Living with depression

Depression is a disorder that can impact major areas of your life. If at any time you feel overwhelmed or have thoughts of self-harm, you can speak with a mental health representative by calling the SAMHSA National Helpline at 1-800-662-4357.

For mental health emergencies, you can also dial 988 to reach the National Suicide and Crisis Lifeline.

To learn more about depression or find resources and support nearby, you can visit:

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Depression is not just a mood or an emotion. It’s an illness, a mental health disorder, and according to some, a disease that affects the entire body.

Although there’s no cure for depression, treatment can help alleviate symptoms and reduce your chance of recurrence.