The government says 1 in 5 American adults suffered from mental illness during the past year. Most didn't receive treatment.

A survey being released Thursday by the Substance Abuse and Mental Health Services Administration found that 45 million experienced some form of mental illness in 2009, from major depression to more serious problems such as suicide attempts. Fewer than 4 in 10 received treatment for their mental health condition.

The survey found a strong link between mental health problems and alcoholism and drug abuse. Mental illness was also more likely among the unemployed, young adults and women. Overall, more than 8 million had serious thoughts of suicide, and 1 million tried to carry them out.