The numbers are astounding.
One in five American adults experience mental illness. One in five children ages 13-18 have, or will have, a serious mental illness. Sixteen million American adults live with major depression.
Yet we often hear things like: “you just have to choose to be happy” or “we all feel sad from time to time.”
Make no mistake. Major depression is not simply a bout of sadness. I know this because I have suffered from major depression. At the time, I didn’t know. In fact, I didn’t really know what was wrong with me until more than 10 years later, when I—a 42-year-old professor!—was sitting in a seminar about major depression and its consequences. The speaker listed the criteria for diagnosing major depression:
  • Depressed mood or a loss of interest or pleasure in daily activities for more than two weeks
  • A mood that is a change from normal
  • Impaired social, occupational, educational functioning
  • Specific symptoms—at least five of the following nine—nearly every day:

  Depressed mood or irritability most of the day, either self-reported or observed by others
  Decreased interest or pleasure in most activates for most of the day
  Significant change in weight (5%) or appetite
  Insomnia at night or excessive sleepiness during the day
  Change in activity
  Fatigue or loss of energy
  Feelings of guilt or worthlessness
  Diminished ability to concentrate, or mere indecisiveness
  Serious thoughts of suicide and how to carry it out

Wow. That was me. I was suffering from major depression: When I quickly lost 20 pounds, becoming thinner than I’d been since age 12. . . . When I camped out under my desk at work in tears for hours on end, with no apparent explanation. . . . When I was up half the night, pacing in my living room. . . . When I thought—often—about how much better off my family would be if I was no longer around. I made bad choices and did stupid things. Normally a control freak, I was out of control. Normally a very careful person, I was extremely careless.
I could have lost the very things I worked so hard for: my family, my job, my life. But I was lucky. I have a strong support system, with people who love and care for me, who look after me. I have a good job, which provides me with good health insurance, and a decent wage. I was able to get the help I needed. Luckily, I have not experienced a bout of depression since.
Millions of people are not that lucky. More than half of adults with a mental illness didn’t receive treatment for it in the previous year; nor did nearly half of young people, ages 8 to 15, with mental illness. The rates are even lower for African Americans and Hispanic Americans suffering from mental health disorders, and research suggests that living in poverty exacerbates these disparities.
The consequences of mental health disorders are severe. An estimated 10.2 million adults in the U.S. with mental health disorders also suffer from addiction. About one-fourth of homeless adults in shelters live with serious mental illness, with countless others on the streets. About a quarter of inmates in state prisons report a recent history of a mental health condition.
What can you do?
Be aware. Know the signs of depression and look after those around you. Ask others to look after you. These conditions do not discriminate—mental illness can afflict anyone regardless of age, race or sex. Pay attention to small changes in the ones you love, and help them to get help. Or seek out help for yourself—there is always someone willing to help, 24 hours a day, seven days a week.
My family recognized that something was wrong and encouraged me to get help. I found a therapist who helped me understand that I had an illness, and what I could do to treat it. I know that I could have a recurrence at any time—researchers are still trying to understand what causes major depression to return and how to prevent it. Until they do, I have to pay attention to my mental health and insist that my family does too.
There is strong evidence that having parents who suffer from depression is a risk factor for depression. Adolescence is a common time for depression to show up, so worrying about the return of my own depression is not enough; I also need to be aware of the signs in my children, who are entering adolescence, and make sure to act at the first sign that something may be wrong.
Fifty percent of all lifetime cases of mental illness begin by age 14, and 75% by age 24. Depression is the leading cause of disability in the U.S. and around the world. Yet government support for research on mental health lags behind that of other areas.
Aren't the numbers astounding?

Leslie McClure is professor and chair of Epidemiology and Biostatistics at Drexel University's Dornsife School of Public Health.

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