How To Define Depression: Understanding This Mental Health Disorder

While people tend to use the word “depressed” to describe their day-to-day sadness, depression is a diagnosable mental illness that usually involves a persistently low mood, a lack of interest in usual activities, and difficulty making decisions, among other physical and psychological symptoms. There can be many types of depression, such as those related to major depressive disorder, persistent depressive disorder, premenstrual dysphoric disorder, bipolar depression, postpartum depression, seasonal affective disorder, and psychotic depression. Mental health services like therapy are often used to treat various types of depression, and therapy can be effective when administered in person or online.

What is depression?

By definition, depression is generally a common but serious mental illness that can impair a person’s daily functioning by causing persistent sadness and a loss of interest in previously enjoyed activities. Those living with this mental illness often lack the energy to complete their day-to-day responsibilities and may find it harder to live life as usual because their negative thoughts and feelings may be unrelenting.  

Symptoms of depression

Like any mental health disorder, depression is usually defined by a group of specific symptoms. According to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), depression can be indicated by the presence of any five of these symptoms continuously over a two-week period:

• A sad mood
• Loss of interest in activities that you once enjoyed
• Fatigue and low energy almost every day
• Changes in weight/appetite (not eating enough or eating all the time)
• Not sleeping at all or sleeping too much
• Problems with memory, concentration, and decision-making
• Guilt and a sense of worthlessness
• Restless, agitated movements (like pacing)
• Slowed speech and movements
• Thoughts of death or suicide or a suicide attempt

Diagnosing depression and its physical symptoms

It can be important to note that these symptoms must be present for an extended time to receive a diagnosis of depression.

While it can be normal to experience some of these symptoms after an upsetting event, like job loss or the death of a family member, it's when these symptoms last for weeks at a time with no change and no relief that they can move out of the realm of sadness into something more serious. Several of these signs and symptoms could also be caused by a physical illness, such as a thyroid problem or vitamin deficiency. These other causes normally need to be ruled out by a medical professional before depression can be diagnosed.

Many people living with depression may also experience physical symptoms. Here are some common ways in which depression might manifest in the body:

• Headaches
• Back pain
• Digestive problems (queasiness, nausea, diarrhea, constipation)
• Joint pain
• Insomnia
• Muscle aches
• Chest pain

Depression can affect your body because it may alter the way your brain registers physical pain. For that reason, if you have any chronic pain, depression may cause it to worsen. For example, if you are prone to migraines or headaches, you may find that these become even more of a problem in a season of depression.

Types of depression

While there can be some defining factors of a depressive episode, depression itself can take many forms. This can make it even more difficult to give a clear definition of this mental health disorder. Below is a list of many of the various kinds of depression.

Major depressive disorder

This is the type of depression we may often talk about if we are trying to define clinical depression. Major depressive disorder is typically characterized by persistent sadness and a loss of interest in previously enjoyed activities. Your doctor might diagnose you with MDD if you've had at least five of the classic symptoms of depression for two weeks or longer and are experiencing impairment in your daily functioning. 

Persistent depressive disorder

Those who are diagnosed with persistent depressive disorder usually experience a sad, dark mood most of the time. They may have also experienced two or more of the other symptoms of depression for at least two years. This type of depression can be unresponsive to treatment and may come and go in bouts.

Premenstrual dysphoric disorder

This disorder might be diagnosed when someone exhibits symptoms of depression every month right before getting their period. In addition to the classic symptoms, those with PMDD may experience additional symptoms of irritability, mood swings, and a poor response to stress.

Bipolar depression

Bipolar disorder, previously known as manic depression, is characterized by a continual fluctuation between manic or hypomanic episodes and depressive episodes. Manic and hypomanic episodes are periods of high energy; depressive episodes, also known as bipolar depression, typically mimic the symptoms of major depression.

Postpartum depression

If you or your partner just had or adopted a child, and you are experiencing a major depressive episode, you might be diagnosed with postpartum depression.

Seasonal affective disorder

This type of depression usually strikes on a recurring basis every year, typically in the fall or winter. Besides the typical symptoms of depression, you may also find that your energy levels decrease dramatically. You can usually be diagnosed with seasonal affective disorder (SAD) if you experience symptoms of depression at the same time of the year for at least two consecutive years.

Psychotic depression

This disorder may be diagnosed if you have symptoms of depression accompanied by psychosis. In addition to the symptoms of a depressive episode, you may hear or see things that aren't there. These delusions and hallucinations are frequently known as psychotic features and may require immediate treatment.

Major depressive disorder and treatment-resistant depression

Treatment-resistant depression is a form of major depressive disorder that does not respond well to typical treatments for depression. For cases such as these, alternative treatments like electroconvulsive therapy (ECT) may be used to diminish symptoms.

Causes of depression

With some diseases, it can be easy to isolate a clear cause. However, this often isn’t the case with depression. Its causes can be complex and might be a combination of several factors. Here are a few of the most common underlying causes of depression:

Genetics

Although we don't yet know the specific reasons for this, studies have consistently shown that having a parent or sibling who lives with depression typically puts you at much greater risk of developing the disorder yourself. 

Stressful events

Substances, medications, and mental health conditions

Depression can also be a side effect of some prescribed medications. Other mental health conditions like substance use disorders are considered risk factors for depression.

Death of a loved one

Losing a loved one can create grief, and major depression can arise as one of the side effects of moving through the grieving process.

Co-occurring mental health conditions and physical illness

Depression frequently co-occurs with other mental health conditions like anxiety disorders and eating disorders, potentially due to an overlap in the negative thought patterns, social factors, and behavioral factors that can contribute to the onset of these conditions.

Additionally, physical and mental health tend to be closely linked. If you are physically ill, it can directly impact your mental well-being. Likewise, living with a chronic illness is generally a stressful circumstance that, over time, can cause you to develop depression. This is usually why it can be important for a doctor to rule out any underlying medical concerns before issuing a depression diagnosis. 

Connections between depression and grief

If you have experienced a loss or a traumatic event, you may exhibit many of the symptoms of depression. Major depression and grief can be closely related, but there are also some important differences between them.

Depression vs. grief: understanding symptoms and differences

Like depression, the symptoms of grief can include a sad mood, changes in appetite, poor concentration and focus, and trouble sleeping. However, after a certain amount of time (which can vary from person to person), these symptoms may gradually become less intense. In contrast, depression tends to last without much relief. Though you may have good and bad days, your symptoms do not usually improve with the passage of time like they often do with grief.

Major depressive disorder and its unique symptoms

Depression may also have some unique symptoms that aren’t as common among those experiencing grief. A sense of worthlessness and extreme guilt tend to be some of the defining symptoms of major depressive disorder. These symptoms are usually not present in uncomplicated grief.

Another way in which grief may be different from depression is that it can still be possible to have happy thoughts and warm feelings evoked by memories of a lost loved one. On the other hand, depression typically carries with it only dark and negative thoughts. If you are depressed, it may seem almost impossible to entertain any thoughts that are positive or happy.

However, there can be times when grief and depression seem to overlap. If the loss was especially traumatic or if you are prone to depression in the first place, grief can linger on indefinitely, never seeming to lift. This is sometimes referred to as complicated grief. When this happens, grief can evolve into major depression and may need to be treated as such.

Therapy for depression

Since depression can vary widely from person to person, it can be difficult to find one clear definition of it. If you’re experiencing symptoms of depression or another mental health disorder, it can be vital to seek the support of a licensed mental health professional. A therapist can offer a safe and supportive environment to process your depression and learn new ways to cope.

Benefits of online therapy

Your symptoms may make it difficult to function as usual, and you may have less energy to make it to in-person appointments with a therapist. With online therapy through BetterHelp, you can meet with your therapist from the comfort of your own home. Having the ability to speak with your provider through video chats, phone calls, or in-app messaging may make it easier to get the support and treatment you deserve, and having some physical distance between you and your therapist may make it less intimidating to get started.

Effectiveness of online therapy

Online therapy can be a helpful tool for individuals living with depression. Researchers have found that online cognitive behavioral therapy (CBT) was generally as effective as face-to-face therapy in treating various symptoms of depression. CBT is a therapeutic framework often used to treat symptoms of depression to teach people how to identify and shift their unhelpful thoughts to create new, more positive ways of thinking. This, in turn, may allow them to change their emotions and behaviors.