A third of Americans are getting less sleep than is recommended. While insufficient sleep is often considered rather common, it can have significant and adverse effects on people’s health. After only one night with too little sleep, a person’s cognitive abilities can be dramatically diminished short term. 

Sleeping habits vary considerably across the country. To determine the states where residents report getting the most and least sleep, 24/7 Tempo reviewed the share of adults in every state who report sleeping less than seven hours per night on a regular basis. These figures were obtained from the 2021 report by the County Health Rankings & Roadmaps, a Robert Wood Johnson Foundation and University of Wisconsin Population Health Institute joint program.

In addition to cognitive abilities, sleeping less than seven hours per night on a regular basis is associated with a range of adverse physical health effects, including increased risk of diabetes, high blood pressure, and coronary heart disease.

Among the 15 states where residents are most likely to get insufficient sleep at night, just four states report a smaller share of adults with hypertension than the U.S. as a whole, and just one state has a lower diabetes rate. 

Poor or insufficient sleep can cause irritability and stress. Quality sleep prevents a chain reaction that starts with signals from the brain to release adrenaline and other hormones, chemicals that cause a person to feel under constant stress. In 13 of the 15 states where residents are most likely to get fewer than seven hours of sleep, people also report more days a month of experiencing mental health problems than the average American. 

Lack of sleep has been shown to be a contributing factor to obesity. Sleep deprivation messes with the two hormones that control appetite — ghrelin, which signals hunger, and leptin, which signals being full. Lack of sleep leads to increased levels of ghrelin (increased appetite) and decreased levels of leptin (diminished feeling of fullness). Of the 15 states where residents are most likely to get insufficient sleep, only two have an obesity rate among residents 18 and over that is lower than the national rate of 29.7%. 

Low income levels appear to increase the likelihood of a population not getting enough sleep. This is likely caused by residents working longer hours at lower-paying jobs and the higher level of stress from financial insecurity. Nationwide, 12.3% of residents live below the poverty line. The poverty rate is higher in all but four of the 15 states where residents are most likely to get insufficient sleep. 

Generally, adults need about seven or more hours of sleep each night, but every one has his or her own optimal sleep time. The quantity, however, is not all that matters. Sleep quality matters, too. Here are 19 secrets to sleep better at night.

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