What Is Depression?

We all get the blues sometimes. But when those bad feelings hang on for weeks or months, it’s probably more than a response to the ordinary hard times that everyone goes through in life. It may be an illness called depression.

If you’re depressed you probably feel sad, discouraged, and hopeless for an extended time. You may have trouble functioning. You might feel exhausted all the time and have difficulty thinking clearly or quickly. Sometimes you might not even feel sad. Instead you feel flat and “blah” and unable to care about anything. The 2023 U.S. Centers for Disease Control and Prevention (CDC) Youth Risk Behavior Survey revealed that 42 percent of high school students felt sad or hopeless almost every day for at least two weeks in 2021. Its findings were especially high with teen girls, with nearly 3 in 5 saying they felt persistently sad or hopeless—the highest level reported over the past decade. One in three girls also said they seriously considered attempting suicide, up nearly 60 percent from a decade ago.

A January 2024 report from the nonprofit organization Common Sense Media found similar results. Its “The State of Kids and Families in America” found that girls are more likely than boys to rank mental health challenges as most important. The majority of teens rate the mental health of youth in their community as just fair or poor. Girls are especially pessimistic, with 69 percent giving these low ratings compared to 59 percent of boys. When asked about causes of the youth mental health crisis, teens cite social media and bullying/discrimination as major contributing factors.

Worldwide, depression impacts about 280 million people, and is the largest cause of disability. Depression is observed in women more frequently than in men, but men are still at risk. Researchers say that men may report depression symptoms differently or may be less likely to seek help for depression, leading to them being diagnosed less often than women.

Unfortunately, most depressed teens never get the professional help they need. Some people believe that only people with serious behavioral disorders seek the help of a mental health expert. But that’s not true. Serious depression isn’t something that you can simply “get over” or break out of. There is nothing wrong with seeking professional help, just as you would if you got a really bad flu.

If you can’t seem to shake the blues—or if you know someone who can’t—you do not have to feel hopeless or alone. Depression can be treated and, in most cases, relieved.

It Can Happen to Anyone

It’s a common belief that people with depression cannot function, but many depressed individuals can actually keep going to work or school. Some take medication or get some other form of treatment. Many try to carry on in spite of their deep emotional pain. Increasingly, celebrities, musicians, and athletes are opening up about depression. Figures including Pete Davidson, Simone Biles, Prince Harry, Kid Cudi, Michael Phelps, Michelle Obama, Cara Delevingne, and Billie Eilish have spoken openly about it to break the stigma.

Some people are able to carry on with their lives despite major depressive episodes. Others are knocked flat by less major ones. Perhaps this shouldn’t be surprising. Some people carry on with their lives when they are very ill—undergoing treatment for cancer, for instance—and others take to their beds at the first sign of a cold. Individuals respond differently to depression, just as they do to other life experiences. Depression is only one part of who a person is.

Depression Statistics

Depression is remarkably common. Most studies show that at any given time, about one in eight American teens has depression, and about 10–20 percent of Canadian youth are affected by a mental illness or disorder. The COVID-19 pandemic saw a threefold spike in depression, especially among those most at risk. At least 15 percent of people will experience a serious depressive episode during their lifetime. Statistically, depression impacts women and girls more frequently, and research is demonstrating that this disparity begins early in the adolescent years. According to a study published in the journal Translational Psychiatry, 36 percent of teenage girls reported depression compared to 13 percent for boys. Depression is also very common among LGBTQ+ youth. The Trevor Project reported in its National Survey on LGBTQ Youth Mental Health 2021 that 62 percent of LGBTQ+ youth report symptoms of a major depressive episode, including more than two in three nonbinary and transgender young people.

Experts say 60 percent of people treated for depression will experience the illness again, and recurrence rates increase the more times the disease has occurred. One out of every three people who have struggled with depression never has another serious problem with it. In a nutshell: Lots of people experience depression, lots of people get over it, and some people may get it again if they’ve had it before.

Symptoms of Depression

People who are depressed may feel sad all the time. But depression can affect people differently. It can affect you physically. For example, depression can make you feel tired, and yet you may have trouble sleeping at night. (Or you might sleep excessively.) You might lose your appetite or you may suddenly start overeating. You may have strange aches and pains and wonder if you are getting sick.

Depression also has emotional and mental symptoms. When you’re depressed, nothing seems to work out the way you’d hoped. Whatever you do seems to go wrong. Even if it doesn’t, you can see only the bad things. After several failures, you begin to think nothing will ever work out. “See—why did I even bother trying?” you might ask yourself. “I knew I was going to mess things up.” A depressed person can feel hopeless, helpless, worthless, and, worst of all, alone. It becomes easy for depressed people to feel trapped by their troubles and become withdrawn.

Types of Depression

Many of the symptoms of mild depression are the same as those of major depression. The difference lies in how severe the symptoms are and how often the person experiences them.

If a person is grieving from loss or the death of a loved one, sadness is a normal reaction that is to be expected. If the sadness persists, however, it may take professional judgment to decide if a person is still grieving or is becoming depressed. Unfortunately, friends, relatives, and family doctors may miss the signs that point to a need for professional help. In such cases, clinical depression (depression requiring treatment) sometimes goes undiagnosed and untreated.

People overlook depression because so many symptoms can hide it. If someone experiences headaches, back pain, irritable bowel syndrome, chronic fatigue, or sleep problems, symptoms of these physical ailments can mask depression. Anxiety, too, often accompanies depression. So someone may experience feelings of panic, shortness of breath, and rapid heartbeat and not recognize the symptoms as being part of underlying depression. In addition, different types of depression present different symptoms that can affect a person to very different degrees. Types of depression are listed below.

• Reactive depression is a temporary depression. It is related to feelings that arise because of a specific life situation. Symptoms can be severe, but they usually subside within two weeks to six months.

• Major depression is a serious condition that can cause someone to be unable to function and possibly even attempt suicide. Major depression can go in cycles, meaning someone who has it might recover from it (sometimes even without treatment), but then it comes back. Treating major depression can make it go away faster and make it less likely to come back.

• Persistent depressive disorder (formerly known as dysthymia) describes a chronically depressed mood. That means the symptoms are less intense than with major depression, but the depression lasts longer. A major depression will be diagnosed if the person has had severe symptoms for two weeks; persistent depressive disorder is diagnosed only after two years of illness. (That doesn’t mean the person should wait two years to seek help!)

• Bipolar disorder (also called manic-depressive disorder) involves major depressive episodes alternating with periods of extremely energetic activity. People who are manic may need very little sleep and be full of ideas, or they may go on wild shopping sprees. But then they crash into a depression. Bipolar disorder is the “roller coaster” of depressions. About 1 percent of the American population experiences bipolar disorder in a given year.

• Atypical depression is not constant. A person with this condition might seem deeply depressed for a few days, then fine for a while, or anxious and cranky.

• Seasonal affective disorder (SAD) is often referred to as “winter blues.” It is a psychological and physical reaction to lack of sunlight. Typically, people who have SAD experience the onset of depression in late autumn. This depression, which can be mild or major, then clears up in early spring, as daylight hours start to get longer. This condition becomes more common as distance from the equator increases. In Greenland, where winter nights go on around the clock, seasonal affective disorder is common.

• Postpartum depression results from the enormous hormonal changes that take place when women give birth and begin the challenges of caring for an infant. Around 70 to 80 percent of new mothers experience minor postpartum depression, sometimes called “baby blues” and lasting a few days. However, for about 10 to 15 percent of mothers, postpartum depression develops into clinical depression.