...according to a U.S. government study. More is needed to better understand and give people the help they need.
Oregon has the highest rate, and New Jersey the lowest, according to 2012-2014 data analyzed by the U.S. Substance Abuse and Mental Health Services Administration (SAMHSA).
Overall, almost 44 million Americans 18 or older had a diagnosable mental, behavioral or emotional disorder in the past year, researchers said. They reviewed national surveys on drug use and health.
"The figures in SAMHSA's report remind us how important it is to take mental health as seriously as any other health condition," Kana Enomoto, SAMHSA acting deputy assistant secretary, said in an agency news release.
The overall national rate of mental illness was about 18 percent.
In Oregon, almost 23 percent of the state residents had any type of mental illness. Utah, West Virginia, Maine and Rhode Island were next, with rates above 21 percent.
In New Jersey, the mentally healthiest state, fewer than 16 percent of adults had a mental health condition, according to the report. The other lowest rates were in Illinois, North Dakota, Florida and South Dakota (all about 16.5 percent).
"The presence of [any mental illness] in every state reinforces that mental illness is a major public health concern in the United States," the report noted. "Overall treatment levels remain low, and addressing the mental health of U.S. adults remains a concern for state and national public health officials.”
Examining changes over time is a key part of such assessments. The report said that rates of past-year mental illness among adults rose in California, Maine, North Carolina and Rhode Island between 2010-2012 and 2012-2014. There was no change in other states.