"It's an interesting juxtaposition," says Doug Thomas, director of the Utah Division of Substance Abuse and Mental Health. "If I knew the answer, I'd be a wealthy man."
While both trends have been apparent for years, there's still no definitive research into why Utahns suffer the highest rate of mental illness while also enjoying relatively good health and well-being.
There are plenty of theories, though, many having to do with cultural influences of the predominant faith, a dearth of psychiatrists and inadequate health insurance even while healthy living is prized, and the fact that statistics can be interpreted in differing ways.
But one idea continues to gain ground in mental health circles: Mental illness might sometimes be linked to altitude.
The theory places Utah in the wider context of Rocky Mountain states, which generally see the same pattern: high mental illness and suicide but otherwise healthy residents. The region is sometimes called the suicide belt.
The elevated brain • Research at the University of Utah and elsewhere so far supports the hypothesis that there's a link between high altitude and increased incidence of mood disorders and suicide.
The theory is that diminished oxygen at high altitudes may affect the brain chemistry in a detrimental way for those prone to depression, bi-polar disorder or schizophrenia. There's also indication that some medicines don't work as well high up.
There are hundreds of studies showing the benefits of athletic training at a higher elevation, and even many showing that people are healthier living at higher altitudes, says Douglas Kondo, a child psychiatrist and researcher at the U.'s Brain Institute.
But there's been little research on altitude's effect on the brain which may change, thanks to a team led by U. psychiatrist Perry Renshaw that is doing research on individual patients, mice and population studies using data from the Centers for Disease Control.
Everyone knows that mountain climbers' thinking can go haywire at high altitudes, and yet skeptics question a mental illness link, says Kondo.
"It's so basic and fundamental," he says, "it strains credulity that someone wouldn't have thought of it before."
And the surveys say ... • In a February report by the Substance Abuse and Mental Health Services Administration, Utah had the highest rate of all mental illnesses in the years 2011 and 2012.
Of adults surveyed in Utah, 22.35 percent reported having mental illness of any kind, including depression, in the prior year.
For serious mental illnesses, the Beehive State had the third highest rate, at 5.14 percent.
The national averages were 18.19 percent for any mental illness and 3.97 percent for serious mental illness.
Other Rocky Mountain states also were above the national average, with Idaho and New Mexico not far behind Utah.
But also in February, the Gallup Healthways Well-Being Index found Utah had the 12th best well-being in 2013 based on 55 measures.
Questions revolved around how respondents felt about their life prospects, health, work, healthy behaviors and access to food, shelter and health care.
That was a big drop from the 2012 index, when Utah was ranked fourth, and was the state's lowest ranking since it debuted at No. 1 in 2008.
Nonetheless, the state also did well in another health study, America's Health Rankings, which put the state at No. 6 in 2013. That study looked at a range of public data on disease, behavior and public policy, and credited Utah's high ranking in part to its low smoking and binge-drinking rates.
Jack Jensen, director of psychological services at Utah Valley University, says it's hard to compare studies that use different methodologies.
Moreover, "just because a minority of the population are determined to be depressed, it really doesn't have an influence on the majority of the population that considers themselves healthy and happy," he writes in an email.
A question of faith • Mental health professionals generally agree about one theory on why Utah stands out in mental illness studies: the predominance of members of The Church of Jesus Christ of Latter-day Saints and the church's high expectations for adherents.
They don't buy it.
"It's an easy thing to say, but it doesn't pan out in the research," says Kim Myers, statewide suicide prevention coordinator.
"It's a sensible theory," says Ted Wander, medical director for LDS Hospital's psychiatric unit and spokesman for the Utah Psychiatric Association. "But it just isn't borne out by the numbers."
LDS teachings that eschew tobacco and alcohol surely influence Utah's low smoking, drinking and cancer rates. But research also shows that religious faith helps protect adherents from mental health problems.
There has been little research, however, about the mental health of those raised in but not practicing a religious tradition.
Jensen at UVU attempted to get at that question in a survey of 1,000 UVU students in 2010. He and colleague Cameron John did not ask for the students' religion, but 85 percent of UVU students identify themselves as LDS.
Students who were active in their faith tradition said the religious community helped them avoid depression, while those who were alienated reported more depression, Jensen says.
Likewise, those who had over-the-top perfectionism were more likely to be depressed.
Jensen cautions that the study showed only correlations, not causation, and that more research is needed.
Hikes, not help • The same survey, Jensen says, indicated that Utahns may be more likely to seek professional help rather than self-medicate with alcohol or drugs. That could explain some of the high rates of residents reporting mental illness.
Other mental health leaders wonder if Utah's shortage of psychiatrists, particularly child psychiatrists in rural areas, means people wait too long.
It can take weeks to get an appointment, says Thomas at the state.
Carol Ruddell, who serves on the Salt Lake Catholic Diocese's disabilities commission and a similar national board, speculated that inadequate insurance might prevent Utahns from getting help promptly.
And she observes that the stigma of mental illness is still far too common.
Myers, the suicide prevention coordinator, wonders if the apparent contradiction between healthy Utah and mentally ill Utah lies in the culture's emphasis on outdoor recreation. Everyone knows where to hike.
"We haven't really had concentrated efforts to say, 'What do we do to take care of our brains?' "