Want To Get A Great Night's Sleep? Head To South Dakota

It's well known that Americans are not getting enough sleep. But some parts of the United States do it better than others. If you bed down in Minnesota, South Dakota or Colorado, you're likely getting seven or more hours a night. But you're less in luck if you live in Hawaii, where only 56 percent of adults get enough rest.

Not that the rest of the country is doing much better. Of the roughly 444,000 Americans polled, about 65 percent got more than seven hours a night according to the study, which was published Thursday by the Centers for Disease Control and Prevention.

And even in the states full of good sleepers, only about 70 percent of adults say they're getting the recommended seven hours or more. "If there was a place where people got 98 percent sufficient sleep, then I'd be impressed," says Dr. Lauren Hale, a family and preventative medicine professor at Stony Brook University.

Overall, states in southeast United States do more poorly on sleep, says Anne Wheaton, an epidemiologist at the CDC and an author on the study. And she thinks that might have to do with other health issues that cluster in the same areas. "If you look at the state map of obesity and frequent mental distress, you'll see similar hot spots," Wheaton says. "These are things that can affect sleep."

Race and ethnicity also tend to correlate with sleep. Nobody sleeps better than white people, according to the CDC report; 54 percent of non-Hispanic blacks get sufficient sleep, about 12 percent less than whites. "What is likely going on is probably explained by demographic composition," Hale says. "Densely populated neighborhoods might have more noise and light. African Americans compared to whites are more likely to live in those neighborhoods."

On top of that, Hale says there are a lot of stressors that non-white communities disproportionately feel that can influence sleep. "There are concerns about racism, not being able to feed one's family, relatives being incarcerated," she says. "One needs to feel safe. If you don't have that internal feeling of security whether financial, physical or emotional, it will be harder to fall asleep."

Lack of sleep has been linked to health problems including obesity, diabetes, high blood pressure, heart disease and stroke, and premature death. It also increases the risk of car accidents and medical errors.

Hawaii, though, is a bit of an anomaly. Wheaton doesn't know why so few Hawaiians, particularly native Hawaiians and Pacific Islanders, get sufficient sleep. "I really have no theories," she says. But, she says states like South Dakota might be doing better because they tend to have better health overall and generally have lower population densities.