Depression Guides & Articles

Karina Thadani
Last updated:
Brindusa Vanta, MD, DHMHS
Medical Editor

What Is Clinical Depression?

Depression is a mood disorder that causes negative thoughts, emotions, and behaviors. Many people experience mild, short-term episodes of feeling blue. However, there are specific criteria required for a clinical depression, or major depressive disorder, diagnosis.

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How Are Depression and Addiction Related?
in Depression

Depression and addiction are complex and can feel impossible to manage—especially if someone is dealing with them simultaneously. Fortunately, help is available for both disorders. Understanding the risk factors, symptoms, and treatment options can help people with dual diagnoses feel more empowered and engaged in their healing process. Relationship Between Depression and Substance Abuse Depression […]

Living With: Postpartum Depression
in Depression

What is Postpartum Depression? There are two forms of postpartum depression. The first form is postpartum or maternity blues, which is a mild mood condition that lasts for a short time. A more severe form, called postpartum major depression, is a serious, potentially life-threatening condition. How Can I Recognize Postpartum Blues? The postpartum blues have […]

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Living With: Depression in Older Adults
in Depression

Depression affects more than 35 million adults each year. Of these, 6.5 million are over the age of 65. In the later years of a person’s life, changes occur that can lead to depression. These include medical illnesses, death of spouses or other loved ones and retirement. Depression prevents older adults from enjoying their lives […]

Depression in Women
in Depression

One in four women will experience an episode of depression at least once in their lives. Depression affects men at a much lower rate. However, many experiences unique to women, such as menstruation, pregnancy, and menopause, trigger depressive episodes. Depression Caused by Menstruation Some women experience severe symptoms of depression before they start menstruating each […]

Depressive Disorder in Older Patients
in Cognitive

Do the Elderly Face Depression? Depression over the age of 65 can be difficult; patients may have difficulty functioning and feel distressed. Later-life depression can be caused by medical illnesses. About 15 percent of people over 65 have symptoms of depression, and these symptoms can make them feel physically ill and increase mortality. Depression can […]

Living With: Depression During Pregnancy
in Depression

Depression during pregnancy is a very difficult and sensitive subject. Statistics from the American Congress of Obstetricians and Gynecologists suggest that between 14 and 23 percent of women suffer from some form of depression during pregnancy. There are many questions that the pregnant woman and her family must struggle with. Is she truly suffering from […]

Depression Treatment Program Options
in Depression

Major depression, also commonly referred to as clinical depression, major depressive illness, unipolar disorder and major affective disorder, is a serious medical illness that is sometimes brushed aside as being less severe than it actually is. Major depression goes beyond the typical feelings of sadness or occasional blue periods. Depression affects your thoughts, feelings, mood, […]

How to Find Help Treating a Depressive Disorder
in Depression

According to the Anxiety and Depression Association of America, approximately 14.8 million Americans suffer from major depressive disorder, and another 1.5 percent of the population struggle with chronic, mild depression called dysthymic disorder. Depression is a mental illness that can have a profound effect on sufferers, often leading to emotional, psychological and physiological problems and […]

Depression Symptoms, Causes and Effects
in Depression

Depression is likely to strike many people to some degree in their lifetime. According to the Centers for Disease Control and Prevention, 9.1 percent of people reported current major or minor depression. If you or someone you know is depressed, it can cause a marked drop in interest in pursuing life to the fullest, and […]

Depression Symptoms

A major depressive episode, which is characterized by a depressed mood that lasts most days for at least 2 weeks, may come with the following symptoms:

  • Persistent sadness and hopelessness
  • Difficulty concentrating and remembering things
  • Loss of interest in hobbies and activities
  • Changes in sleep patterns (either too little or too much sleep)
  • Fatigue or loss of energy nearly every day
  • Changes in appetite (either increased or decreased appetite), leading to weight changes
  • Restlessness or feeling slow
  • Feeling excessive worthlessness or guilt
  • Suicidal thoughts 1

In the United States, over 20 million adults have experienced depression at some point, according to data from 2020. 2 When left unaddressed, this mood disorder can greatly impact day-to-day life, including the ability to complete work obligations or maintain social relationships.

Although many people suffer from clinical depression, the cause isn't always clear. Researchers suggest that genetics, hormones, environment, brain chemistry and other factors play a role in the development of depression. 3 It's worth noting that there are different types of depression, each of which has its own cause.

Types of Depression

Major depressive episodes aren't the only type of depression a person can experience. Other forms of depression include the following.

  • Persistent depressive disorder (PDD): PDD is a mild to moderate form of chronic depression. It occurs when someone experiences depression for over 2 years. 4
  • Postpartum depression (PPD): As the name suggests, this type of depression impacts women after pregnancy. 5
  • Seasonal affective disorder (SAD): This is a temporary form of depression associated with seasonal changes. Typically, it arises during the winter. 6
  • Bipolar disorder: Formerly called manic depression, this disorder causes sudden mood changes. 7
  • Psychotic depression: Put simply, psychotic depression is a form of clinical depression that comes with psychotic features like hallucinations and delusions. 8 Psychotic depression is also common among the elderly.
  • Premenstrual dysphoric disorder (PMDD): PMDD is connected to a woman's menstrual cycle. It causes depression and increased irritability. 9

In 2017, over 264 million people across the globe experienced some form of depression. 10 Considering they're all classified as types of depression, these conditions share many similarities. For example, they each cause symptoms like sadness, hopelessness, and loss of interest in previously enjoyable activities. However, they also have some key differences. To better understand these differences, here's a closer look at a few of the most prevalent depression types.

What Is Major Depression?

Major depression, also called major depressive disorder (MDD) and clinical depression, is one of the most common forms of depression. As mentioned earlier, it impacts over 20 million Americans and is characterized by a consistently poor mood that occurs nearly every day for 2 weeks and interferes with day-to-day life. If it continues for over 2 years and the symptoms are mild to moderate, it becomes persistent depressive disorder.

For diagnosis, must experience at least five out of nine symptoms listed in the diagnostic criteria for a major depressive episode. There are many factors that can increase a person's risk factors of MDD, including substance use, a negative environment, and having a family history of depression. 11

What Is Postpartum Depression?

After giving birth, it's common for women to feel sad, hopeless, or overwhelmed. Many women also have difficulty sleeping or experience episodes of intense crying. These emotions and behaviors are known as "the baby blues" and generally fade after a few days. If they last for more than 2 weeks, it's called postpartum depression (PDD). Women with PDD typically experience the following:

  • Empty, sad emotions
  • Sadness that impacts day-to-day life
  • Feeling disconnected from their child 12

PDD is a fairly common condition that impacts about one in seven women. 13 Although it can affect any new mother, it's more common among women who have a family history of depression, experience a lack of familial support, or have struggled with depression during their pregnancy. 14

What Is Seasonal Depression?

Seasonal depression, or seasonal affective disorder (SAD), is a form of depression that's directly connected to the seasons. For most people, SAD begins during autumn, continues throughout the winter, and resolves around springtime. In addition to causing common major depression symptoms, SAD may result in the following:

  • Oversleeping
  • Weight gain and cravings for carbohydrates
  • Persistent low energy 15

SAD affects up to 3% of the general population and up to 20% of MDD patients. 16 While the cause isn't certain, research suggests it may be connected to the lack of sunlight in the winter. Reduced sunlight is associated with lower levels of serotonin (a brain chemical that impacts mood), as well as lower levels of vitamin D. 17

How to Know If You Have Depression

Unlike most physical medical conditions, depression cannot be diagnosed through blood or laboratory work. The best way to determine if someone has depression is by analyzing symptoms. Anyone who notices persistent sadness that affects day-to-day life should speak with their doctor.

During a consultation, doctors will ask about symptoms. They may also inquire about risk factors, such as family history or substance use. If they suspect depression, the next step is treatment. 18

How to Treat Depression

Treatment for depression varies depending on the cause. Oftentimes, doctors recommend a combination of antidepressants and talk therapy.

Antidepressants are a type of medication that impacts brain chemicals known to influence mood. In many cases, antidepressants have a positive effect on depression symptoms — in one study, between 40% and 60% of patients who took them noticed an improvement in mood within 8 weeks. 19

Along with medication, many doctors recommend psychotherapy (or talk therapy). One of the most common depression treatments is cognitive-behavioral therapy. During these sessions, patients work with counselors to transform negative thought patterns into positive ones. 20

How to Deal With Depression

Being diagnosed with depression isn't easy. Many people feel guilty or ashamed about their emotions, which causes them to try and hide their depression. 21 Over 50% of people with a mental illness do not seek treatment. 22 Unfortunately, withdrawing from others can actually worsen symptoms and increase negative thoughts.

Whether someone has temporary SAD or long-lasting PDD, it's essential to seek the support of loved ones and speak to a doctor about symptoms. Many individuals with depression patients eventually experience symptom relief after starting treatment. 23 To learn more, visit How to Find Help Treating a Depressive Disorder.