Americans in general do not sleep well. But those who sleep the worst live in the South, according to a new study by the Journal of Clinical Sleep Medicine. 24/7 Wall St. looked at the six states with the highest rates of sleep disturbance and identified a number of quality of life indicators that may help residents of some states sleep better than others.

The researchers characterize sleep disturbance as “problems falling asleep, problems staying asleep, and/or sleeping too much.” According to the study, the states with the highest rates of sleep disturbance have a number of other traits in common. “Regional differences in sleep disturbance could be explained by a number of factors, the strongest of which being differences in mental and physical health, healthcare access, smoking, latitude/longitude and body mass index,” Dr. Michael Grandner, lead author of the study, told 24/7 Wall St.

The data 24/7 looked at certainly supports Dr. Grandner’s explanation. Obesity, as measured by body mass index, is high in all six states with the poorest sleep. Three of the states have the absolute highest obesity rates in the country, and the other three are in the top 12. Obesity often implies poorer health. All six states with the worst sleep are also among the top 11 states with the highest smoking rates among adults. West Virginia, which has the highest rate of sleep disturbance, also has the highest rate of smokers in the country.

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Income may also be related to sleep disturbance, although this is not mentioned in the study. There are well-established relationships between low income and mental and physical health. Five of the six states with the worst sleep are also among the 10 states with the lowest median household incomes in the country, and the sixth falls among the lowest 15.

The researchers of the original report identified the states with the highest rates of sleep disturbance by asking 157,319 participants from 33 states a number of questions regarding the quality of their sleep in the 14 days leading up to questioning. In addition to the data published in the Journal of Clinical Sleep Medicine, 24/7 Wall St. looked at data from the Census Bureau, the Centers for Disease Control and Prevention and the American Human Development Project.

These are the six worst states for sleep.

6. Missouri
> Prevalence of sleep disturbance: 21.3%
> Obesity: 30.5% (10th highest)
> Adult population who smoke: 21.1% (11th highest)
> Median income: $44,301 (14th lowest)

More than one in five of surveyed Missouri adults reported difficulty falling asleep, staying asleep or sleeping too much. The state’s population is generally unhealthy, with a high smoking rate and more than 30% of the population overweight. According to the study, there is a strong correlation between general health and good sleep. Missouri has the 11th-shortest life expectancy in the U.S. at 77.4 years.

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5. Arkansas
> Prevalence of sleep disturbance: 22.1%
> Obesity: 30.1% (12th highest)
> Adult population who smoke: 22.9% (4th highest)
> Median income: $38,307 (3rd lowest)

All of the states with the highest prevalence of sleep disturbance are located in poor, southern states. Arkansas is no exception to this. The state’s median income is just $38,307, the third-lowest in the country. A whopping 18.4% of the population lives below the poverty line — the third highest rate in the country. According to the study, 22.1% of the population is reporting having trouble sleeping.

4. Alabama
> Prevalence of sleep disturbance: 22.3%
> Obesity: 32.2% (3rd highest)
> Adult population who smoke: 21.9% (8th highest)
> Median income: $40,474 (5th lowest)

Life expectancy in Alabama is the third-lowest in the country. This is a reflection of the general health of the population, which is extremely poor. Nearly one-third of Alabamans are overweight, and more than one-fifth are regular smokers. The state also has the seventh-highest cancer rate and the seventh-highest rate of heart disease. A staggering 13.2% of the population has diabetes, the highest rate in the country. Sleeping troubles are also an issue in the state. More than 22% of the population report some type of sleep disturbance.

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3. Mississippi
> Prevalence of sleep disturbance: 22.4%
> Obesity: 34% (the highest)
> Adult population who smoke: 22.9% (5th highest)
> Median income: $36,851 (the lowest)

General health in Mississippi is one of the worst in the U.S. It has the highest rate of obesity in the country, at 34% of the total population. It also has among the highest rates of smoking in the country of 22.9%. Life expectancy in the state is just 74.8 years — the shortest estimated lifespan of any state. State residents are also extremely poor. Mississippi’s median household income is just $36,851 and the poverty rate is 21.8% — the worst state in both categories. Over 22% of state residents report experiencing sleep disturbance.

2. Oklahoma
> Prevalence of sleep disturbance: 24.7%
> Obesity: 30.4% (11th highest)
> Adult population who smoke: 23.7% (3rd highest)
> Median income: $42,072 (8th lowest)

Oklahoma has the third-highest rate of smoking among its adult population in the country. Although its obesity rate is not one of the highest, ranking 11th among the states, it still exceeds 30%. Like other state with the highest levels of sleep disturbance, median income is among the lowest in the country.

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1. West Virginia
> Prevalence of sleep disturbance: 26.0%
> Obesity: 32.5% (2nd highest)
> Adult population who smoke: 26.8% (the highest)
> Median income: $38,218 (2nd lowest)

West Virginia is a largely unhealthy state. It has the second-most obese population in the country and the largest percentage of smokers. Although the measure is not mentioned in the report, life expectancy can be one of the most telling figures when it comes to physical health. West Virginia has the second-lowest life expectancy in the country, at 75.2 years.

Charles B. Stockdale