For the third year in a row, Hawaii snagged the No. 1 spot as the least stressed state, while Utah and Kentucky kept their distinctions as the two most stressed U.S. states, according to Gallup poll results released Wednesday.

Overall, an average of 40 percent of American adults reported experiencing stress when asked whether they experienced it "a lot of the day yesterday," according to the survey by Gallup-Healthways Well-Being Index. As such, Gallup officials say further studies are needed to tease out what drives stress and how it affects people. Past research has shown job stress is linked with weight gain; stress in general can make you more susceptible to health conditions ranging from the common cold to cancer.

Low-stress states — ones that have less than 38 percent of residents experiencing stress — were primarily located in parts of the Midwest. Those with 40 percent or more residents reporting a lot of stress were clustered in the West and Northeast, though they also included other states.

Here are the five most stressed states and the percentage of residents who said they had experienced stress "a lot of the day" the prior day:

  • Utah: 45.1 percent
  • Kentucky: 44.9 percent
  • West Virginia: 43.6 percent
  • Idaho: 43.0 percent
  • Massachusetts: 42.6 percent
Five least stressed states:
  • Hawaii: 30.2 percent
  • Wyoming: 34.4 percent
  • North Dakota: 34.6 percent
  • South Dakota: 35.5 percent
  • District of Columbia: 36.7 percent
[See full list of U.S. states and stress]

Stress is a complex emotion, it seems, with no one factor explaining the least- and most-stressed regions. For instance, some frazzled states have more low-income residents, while others are home to wealthier individuals. Stressed-out Kentucky and West Virginia have residents who tended to be poor in health; Utah and Massachusetts, coming in at No. 1 and No. 5 on the most-stress list, respectively, boasted of physically healthy residents. [Read: Happiest States of 2010]

But perhaps stress isn't always such a downer. Residents of the highly stressed Connecticut, Utah and Massachusetts rated their lives highly. (Residents answered a question about which step on a ladder they would rate their lives now and in five years, with the top step representing the best possible life and the bottom rung the worst possible life.)

Stress levels decreased at least somewhat for residents living in about half of the states in 2010, as compared with 2009; the year prior (2009 compared with 2008), residents' stress levels increased in most states. The fact that there wasn't an increase in 2010 during the recessions suggests that our definition of stress goes beyond economics.

The results are based on telephone interviews conducted Jan. 1 through Dec. 31, 2010, with a random sample of 352,840 adults, ages 18 and older, living in all 50 U.S. states and the District of Columbia.

This article was reprinted with permission from LiveScience.

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