When compiling our list of the best cities for sleep, we started with sufficient vs. insufficient sleep and then tied in some other crucial metrics. How did we pick these metrics in particular? We looked at the latest research and found a strong connection between healthy sleep and certain behaviors and environmental factors.
Here’s the breakdown of the data we chose:
Adult obesity rates
The current obesity rate in the United States hovers around 35%. Rates of obesity tend to be more prevalent in the south but are increasing country wide. We looked at obesity rates by state to help us rank the best cities for sleep. Why obesity? A larger body mass index is strongly associated with sleep apnea, a sleep disorder characterized by pauses in breathing, daytime sleepiness, and an increased risk of diabetes and cardiovascular disease. (1)
Obesity can also contribute to insomnia and other sleep disorders such as hypersomnia (excessive sleeping) and restless legs syndrome. Weight gain and changes in fat metabolism can result from long-term sleep deprivation and sleep apnea. Obesity can also cause other sleep-related issues such as snoring and a chronic lack of oxygen called obesity hypoventilation syndrome.
Number of mentally healthy days
Depression and other psychiatric disorders can cause sleep disorders, and sleep disorders can contribute to psychiatric issues. (2) An analysis of major studies revealed that volunteers who suffered from insomnia symptoms were twice as likely to be diagnosed with depression as those without sleep difficulties. Medications to treat psychiatric disturbances can also cause insomnia.
Though the connection between mental health and sleep disorders isn’t entirely understood, it is well-known that hormones and neurotransmitters are affected by poor sleep and may have a strong influence on mood and the development of psychiatric conditions. Because of the significant impact of mental health on sleep disorders, we gave the number of mentally healthy days significant weight when compiling our list of the best cities for sleep.
We included excessive alcohol consumption on our list due to its effect on REM sleep and overall sleep quality. Rates of drinking are increasing in the United States, particularly among women, older people, and lower income groups. Binge drinking rose nearly 30% between 2002 and 2013, while alcohol abuse surged 50%.
Studies prove that alcohol can reduce sleep efficiency and change sleep patterns. (3) Although alcohol can reduce the time it takes to fall asleep, it can cause waking during the night once its effects on the central nervous system wear off. For these reasons, we included the drinking habits of a city’s residents in our data when selecting the best cities for sleep.
Because physical activity can impact sleep and the circadian rhythm, we included exercise — or the lack of it — when making our list of slumber-friendly cities. Studies show that exercise has a positive effect on sleep, particularly in people with chronic insomnia. (4) Exercise impacts the effect of stress hormones like cortisol and adrenaline, which can contribute to hyperactivation of the central nervous system, a common cause of insomnia.
Sufficient sleep is also necessary for the proper functioning of muscles and the repair and rebuilding of tissues after a workout. The majority of muscle regeneration takes place during sleep when growth hormone is released by the pituitary gland. It’s no coincidence that cities with a higher percentage of regular exercisers tend to rank higher on our list of best cities for sleep.
Smoking or consuming nicotine in any form is a hazard to sleep health. Nicotine is a powerful stimulant that can prevent or delay sleep. (5) Withdrawal from nicotine is a common cause of insomnia, as well. Because of its effect on the lungs and blood vessels, nicotine can increase breathing disorders that impact sleep, such as asthma and sleep apnea. Although vaping does not involve the inhalation of smoke, it can deliver more powerful stimulant effects than smoked nicotine, disrupting sleep even further.
Studies show that people who consume nicotine in any form spend less time in deep sleep, particularly during the early part of the night when blood levels of nicotine are highest. Sleep can also be disrupted as nicotine levels drop toward morning and cravings increase. The data is so convincing that we included nicotine use on our list of behaviors that influence sleep.
Air pollution was a key factor in our rankings of the best cities for sleep. Metrics included particulate pollution from cars and ozone levels. Higher levels of air pollution are linked to increased rates of asthma, cardiovascular disease, chronic obstructive pulmonary disease, and lung cancer. (6) There is a strong connection between asthma and obstructive sleep apnea, which can cause weight gain, heart problems, increased risk of stroke, and diabetes.
Air pollution can also cause upper airway congestion, leading to snoring and raising the risk of sleep apnea. Cities with higher levels of pollutants experience more days of unhealthy air quality, making physical exercise and outdoor activities more harmful to the lungs. Air pollution is often caused by urban conditions including traffic and construction, which can create a noisy environment that further disrupts sleep.
We added food insecurity to our list of important sleep metrics because of its influence on physical and mental health. (7) Food insecurity describes a lack of available food, lack of access to food, and/or a lack of food that contains adequate nutrition. A recent study showed that people who sleep less than seven hours a night tend to consume fewer vitamins and minerals such as A, D, and magnesium.
The US government measures food insecurity by asking questions on the Census Bureau’s Current Population Survey. Not surprisingly, food insecurity is more common in lower-income households. People who don’t eat enough nutritious food are more likely to suffer from health problems, which can also cause sleep issues.
Food insecurity is a significant source of stress. The anxiety, hunger, and economic uncertainty associated with lack of food or inadequate nutrition can contribute to poor sleep and insomnia. Sleep difficulties can also make work or school more challenging and cause further economic hardship.
Number of unemployed residents
Like food insecurity, unemployment can contribute to chronic sleep issues. Unemployment can also lead to hypersomnia, or excessive sleep and sleepiness. Longer-term unemployment may trigger depression, which is strongly associated with sleep difficulties, especially insomnia. Unemployment can go hand in hand with other issues that have a negative effect on sleep, including inconsistent income, poor living conditions, depression and/or anxiety, and substance abuse.
A recent study shows that people with sleep apnea are more likely to have a history of job loss and unemployment. (8) Sleep disorders can result from job loss and contribute to it, as well. This may be because sleep apnea, insomnia, and other sleep difficulties can cause illness, diminished brain function, irritability, and other physical and emotional effects that make keeping a job more difficult.
In our search for the best cities for sleep, we included data on median income. Studies show that more sleep may equal more income, particularly over time. (9) Sleep improves productivity, which can directly correlate to a higher salary. Better work performance is linked to adequate sleep, while poorer performance, including on-the-job accidents and mistakes, is tied to poor sleep.
Workers tend to make more money in cities where the residents get more sleep. Just one extra hour of sleep each week could lead to 5% more earnings over the long-term. People who live in cities where it gets darker earlier generally sleep more and make a higher salary than people who live in areas where the sun goes down later. This is probably related to the body’s circadian rhythm, which is designed to respond to light cues and cause sleepiness once night falls.
Perhaps the most crucial metric we looked at is insufficient sleep. Most adults need between seven and nine hours of sleep each night, but more than a third of US adults get less than that. Insufficient sleep can be caused by a number of reasons, including mood disorders, stress, sleep apnea, negative psychological associations with the bed and sleep, medications, and chronic pain. Lack of sleep accounts for about $400 billion in lost productivity each year.
Insufficient sleep is linked to serious and potentially irreversible health effects. Possible consequences of short-term sleep loss include fatigue, trouble concentrating, irritability, and a higher risk of illness. Sleep deprivation over the long term can lead to obesity, diabetes, heart disease, and dementia. Insufficient sleep also increases the risk of microsleep episodes, which can lead to car accidents and workplace injuries. (10)
Cities where residents sleep fewer than the recommended number of hours may have a greater risk of certain medical conditions and unhealthy behaviors. People in the Appalachias get the least amount of sleep and also report higher rates of obesity, physical inactivity, and smoking.
- Beccuti G, Pannain S., Sleep and Obesity, Current Opinion in Clinical Nutrition and Metabolic Care, July 14, 2011
- Krahn LE., Psychiatric disorders associated with disturbed sleep, Seminars in Neurology, March 25, 2005
- Stein MD, Friedmann PD., Disturbed Sleep and Its Relationship to Alcohol Use, Substance Abuse, November 10, 2009
- Chang JJ, Pien GW, Stamatakis KA, Brownson RC., Association between physical activity and insomnia symptoms in rural communities of southeastern Missouri, Tennessee, and Arkansas, Journal of Rural Health, June 29, 2013
- Jaehne A, Unbehaun T, Feige B, Lutz UC, Batra A, Riemann D., How smoking affects sleep: a polysomnographical analysis, Sleep Medicine, December 13, 2012
- Billings ME, et al., The Association of Ambient Air Pollution with Sleep Apnea: The Multi-Ethnic Study of Atherosclerosis, Annals of the American Thoracic Society, March 16, 2019
- Meng Ding, Food Insecurity Is Associated with Poor Sleep Outcomes among US Adults, The Journal of Nutrition, March 2015
- Jose R. Bautista, et al., Individuals with Obstructive Sleep Apnea have Higher Likelihood of Multiple Involuntary, Job Losses, Sleep, April 2019
- Mattew Gibson, Time Use and Labor Productivity: The Returns to Sleep, The Review of Economics and Statistics, December 2018
- Williamson AM, Feyer AM., Moderate sleep deprivation produces impairments in cognitive and motor performance equivalent to legally prescribed levels of alcohol intoxication, Occupational and Environmental Medicine, October 2000