Depression can hit with the force of a tornado, tearing down lives and wrecking stability, but treatment is effective in four out of five cases.

It’s almost as prevalent these days as the common cold. Nearly everyone claims to have suffered it at some point in life. Children as young as 2 may develop it, as may mothers with newborns or men in the midst of life.

You guessed it: I’m talking about depression, the No. 1 mental health problem in America.

At any one time, more than 10 percent of the population is being treated for some form of depression. That means about 22 million people are spending millions of hours on therapists’ couches and popping millions of antidepressants daily. Little wonder that Elizabeth Wurtzel — beautiful, clever and for many years depressed — titled her best-selling treatment memoir Prozac Nation.

Depression takes three main forms. The most severe is major depression, where the largest number of symptoms comes into play. Dysthymic depression is similarly chronic, but often the only symptom is an almost daily depressed mood that can last for years. Bipolar disorder is the third form, characterized by behavior that cycles between mania and depression. Mania may not look like depression to the untrained eye, but its high-energy symptoms are a kind of parody of happiness. Manics have delusions of grandeur, are excitable and voluble, never tire, seldom sleep, and have little need for food.

The curious thing about depression is that it can surface at any time in life. In recent years, physicians and therapists have been coming to terms with the fact that the threshold for depression has been getting lower and lower, in some instances starting in infancy. Childhood depression often begins with another disorder or emotional problem, such as Attention Deficit Disorder or hyperactivity, and then it literally evolves.

According to the National Institute of Mental Health, around 2.5 percent of children and 8 percent of adolescents in America suffer from some form of clinical depression.

Dr. David Fassler, chairman of the Council on Children, Adolescence and their Families at the American Psychiatric Association, is the first to admit that his field has seen a revolution.

“When I was at medical school,” he says, “we were taught that children weren’t emotionally mature enough to experience depression. Now we know that at any time something like 5 percent of children in America are depressed and that over half of depressed adults seeking treatment report being depressed in childhood or adolescence.”

Depression in children can have the same effects as in adults: The child will seem sad, will cry and mope, lose his appetite and sleep badly. Often, however, depression manifests itself as agitation or irritability, and the child will get into trouble at school, play truant, get involved in drugs or become sexually promiscuous. In either case, it is important for teachers to recognize whether such symptoms represent a change in the child, and to determine whether the symptoms are lasting. Children who are identified as depressed tend to respond well to treatment.

“Parents, too, need to realize that it’s not their fault if their child is depressed and that their child cannot simply snap out of it,” says Fassler.

It’s helpful for parents to learn which factors can reduce the risk of depression, especially in children who’ve already had an episode, and ways they can advocate for them during hard times, says Fassler.

“These include establishing a secure environment, so making the world relatively predictable; fostering open and honest communication, so your kids know they can talk to you about anything; adopting a constructive approach to discipline; and encouraging your kids to take up activities that will enhance their self-esteem.”

Parents with children suffering from bipolar disorder tend to have the most difficult experiences. (In 2013, the American Psychiatric Association reclassified bipolar disorder in children as disruptive mood dysregulation disorder.

In children with this disorder, every day their moods may swing through the gamut of human emotion. It’s exhausting for them — many are filled with rage and flip between hyperactivity and seemingly endless tantrums — and for their parents. One parent, a single mother with a 9-year-old son, said, “Hearing your child tell you that they want to die is crushing. It’s just not what you expect to hear.”

Considering the high rate of treatment success for depression, it’s clear that lack of diagnosis is a large part of the problem. The best results, says Fassler, come from a combination of individual and family therapy and medication. Teenage depression goes undiagnosed most frequently because people assume that a heavy dose of Sturm und Drang comes with the territory, that mood swings are harmless and hormonal. Signs of depression to watch out for include an attraction to risk-taking — experimenting with drugs and alcohol, promiscuity and fast cars — as well as its opposite, extreme social withdrawal.

Dr. Allan Cooperstein, a clinical and forensic psychologist affiliated with Philadelphia’s Northwestern Hospital, works with depressed adults. He says that at the core of depressive behaviors and causes “is one single common denominator: It’s truly a depression of something.

“If you consider emotions to be a palate of colors, and an individual, through their socialization, is taught never to express anger, the anger is still there, but it’s internalized. It’s like they’ve been told never to use blue, so they have to depress it to keep it out of sight.”

For instance, if you came from a home where machismo ruled and you were taught to hide fear, you might become depressed, and the root of your depression would be fear.

“There are even examples,” says Cooperstein, “where happiness triggers depression. A journalist might feel happy every time she get something published, but then she may be assailed by fear that it will be the last article she will ever have published. This is like the kid who comes home with an A grade and whose parents say ‘make sure you get an A next time, too.’”

This sort of person will always sabotage their happiness, because deep down they suspect they don’t deserve it.

Depression can also be summoned by persistently ignoring your needs. Cooperstein cites an example of a PhD student who finished his dissertation and then committed suicide. First he ignored his emotional needs in order to complete his PhD, becoming depressed in the process, and then he ignored his depression in order to finish. When he did, the whole torrent of dissatisfaction washed over him, ultimately drowning him.

Adults usually try to ward off their depression, though their attempts are often unconscious. “One person may try to deal with depression by going on spending sprees. In essence, they’re trying to run ahead of their depression. Someone else may try to offset its effects by comfort eating. Alcohol and drug abuse, too, are forms of self-medication,” says Cooperstein.

The good news is that with treatment, nearly 80 percent of people with depression show an improvement in their symptoms within four to six weeks of beginning medication, psychotherapy, attending support groups or a combination. Despite its high treatment success rate, however, nearly two out of three people suffering with depression do not actively seek or receive proper treatment. This is particularly true of seniors.

According to the World Federation for Mental Health, of the 32 million Americans over age 65, nearly 5 million experience serious symptoms of depression. Many seniors have to contend with a high level of loss — loss of social status and self-esteem, loss of physical capacities and the death of friends and loved ones.

Kathryn Riley, associate professor of Preventative Medicine at the University of Kentucky, says that resistance to treatment is a big problem. “People who are old now do not seek out mental health treatments; (such help is) simply not part of their life experience. Yet when treatment is made available, they make great strides.

“Untreated, people can get so depressed they lose hope, stop taking care of themselves and end up in nursing homes, even though physically there may be little wrong with them. Among elderly men in particular, suicide is also a major problem.”

Riley cites a form a behavior therapy that reintroduces pleasurable activities slowly, to create what she calls an “upward spiral.” Intergenerational activity also is valuable in helping the elderly regain outside interests.

There’s no question that depression is a debilitating disorder that some people have to manage for the rest of their life. It’s important to remember, however, that treatments for it are statistically among the most effective in the area of mental health. Perhaps we just need to get better at spotting the symptoms of depression and offering help.

Learn more: Depression Information, Symptoms, and Treatment

Depression is the cause of more than two-thirds of the 30,000 reported suicides in the United States each year (White House Conference on Mental Health, 1999; National Institute of Mental Health, 2016).

An estimated 16.2 million adults in the United States had at least one major depressive episode. This number represented 6.7 percent of all U.S. adults. The prevalence of adults with a major depressive episode was highest among individuals aged 18-25 (10.9%) (National Institute of Mental Health, 2016).

Women are disproportionately affected by depression, experiencing it at twice the rate of men. This 2:1 ratio exists regardless of racial and ethnic background or economic status. The annual prevalence of major depressive episode was higher among adult females (8.5%) compared to males (4.8%). The lifetime prevalence of major depression is 20 to 26 percent for women and 8 to 12 percent for men, generally because men do not report their symptoms or seek treatment as readily as women (Journal of the American Medical Association, 1996).

Clinical depression costs the United States $44 billion annually, including workplace costs for absenteeism and lost productivity ($23.8 billion), direct costs for treatment and rehabilitation ($12.4 billion) and loss of earnings due to depression-induced suicides ($7.5 billion). (Analysis Group and Massachusetts Institute of Technology, Journal of Clinical Psychiatry, 1993).