Prevalence of Healthy Sleep Duration among Adults - United States, 2014

Abstract

To promote optimal health and well-being, adults aged 18-60 years are recommended to sleep at least 7 hours each night (1). Sleeping <7 hours per night is associated with increased risk for obesity, diabetes, high blood pressure, coronary heart disease, stroke, frequent mental distress, and all-cause mortality (2-4). Insufficient sleep impairs cognitive performance, which can increase the likelihood of motor vehicle and other transportation accidents, industrial accidents, medical errors, and loss of work productivity that could affect the wider community (5). CDC analyzed data from the 2014 Behavioral Risk Factor Surveillance System (BRFSS) to determine the prevalence of a healthy sleep duration (≥7 hours) among 444,306 adult respondents in all 50 states and the District of Columbia. A total of 65.2% of respondents reported a healthy sleep duration; the age-adjusted prevalence of healthy sleep was lower among non-Hispanic blacks, American Indians/Alaska Natives, Native Hawaiians/Pacific Islanders, and multiracial respondents, compared with non-Hispanic whites, Hispanics, and Asians. State-based estimates of healthy sleep duration prevalence ranged from 56.1% in Hawaii to 71.6% in South Dakota. Geographic clustering of the lowest prevalence of healthy sleep duration was observed in the southeastern United States and in states along the Appalachian Mountains, and the highest prevalence was observed in the Great Plains states. More than one third of U.S. respondents reported typically sleeping <7 hours in a 24-hour period, suggesting an ongoing need for public awareness and public education about sleep health; worksite shift policies that ensure healthy sleep duration for shift workers, particularly medical professionals, emergency response personnel, and transportation industry personnel; and opportunities for health care providers to discuss the importance of healthy sleep duration with patients and address reasons for poor sleep health.

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165 QuickStats
To promote optimal health and well-being, adults aged
18–60 years are recommended to sleep at least 7 hours each night
(1). Sleeping <7 hours per night is associated with increased risk
for obesity, diabetes, high blood pressure, coronary heart disease,
stroke, frequent mental distress, and all-cause mortality (2–4).
Insufficient sleep impairs cognitive performance, which can
increase the likelihood of motor vehicle and other transportation
accidents, industrial accidents, medical errors, and loss of work
productivity that could affect the wider community (5). CDC
analyzed data from the 2014 Behavioral Risk Factor Surveillance
System (BRFSS) to determine the prevalence of a healthy sleep
duration (≥7 hours) among 444,306 adult respondents in all
50 states and the District of Columbia. A total of 65.2% of
respondents reported a healthy sleep duration; the age-adjusted
prevalence of healthy sleep was lower among non-Hispanic blacks,
American Indians/Alaska Natives, Native Hawaiians/Pacific
Islanders, and multiracial respondents, compared with non-
Hispanic whites, Hispanics, and Asians. State-based estimates of
healthy sleep duration prevalence ranged from 56.1% in Hawaii
to 71.6% in South Dakota. Geographic clustering of the lowest
prevalence of healthy sleep duration was observed in the southeast-
ern United States and in states along the Appalachian Mountains,
and the highest prevalence was observed in the Great Plains states.
More than one third of U.S. respondents reported typically sleep-
ing <7 hours in a 24-hour period, suggesting an ongoing need for
public awareness and public education about sleep health; worksite
shift policies that ensure healthy sleep duration for shift workers,
particularly medical professionals, emergency response personnel,
and transportation industry personnel; and opportunities for
health care providers to discuss the importance of healthy sleep
duration with patients and address reasons for poor sleep health.
BRFSS* is a state-based, random-digit–dialed telephone survey
of the noninstitutionalized U.S. population aged ≥18 years. BRFSS
is conducted collaboratively by state health departments and CDC
(6) among both landline and cell phone respondents, and data are
weighted to state population estimates. Response rates for BRFSS
are calculated using standards set by the American Association
of Public Opinion Research Response Rate Formula #4.† The
response rate is defined as the number of respondents who com-
pleted the survey as a proportion of all eligible and likely eligible
persons. The median response rate for all states and territories in
2014 was 47.0% and ranged from 25.1% to 60.1%.
Survey respondents in 2014 were asked, “On average, how
many hours of sleep do you get in a 24-hour period?” Hours of
Prevalence of Healthy Sleep Duration among Adults — United States, 2014
Yong Liu, MD1; Anne G. Wheaton, PhD1; Daniel P. Chapman, PhD1; Timothy J. Cunningham, ScD1; Hua Lu, MS1; Janet B. Croft, PhD1
* 2014 BRFSS Summary Data Quality Report (http://www.cdc.gov/brfss/
annual_data/2014/pdf/2014_DQR.pdf).
† http://www.aapor.org/Standards-Ethics/Standard-Definitions-(1).aspx.

Morbidity and Mortality Weekly Report
138 MMWR / February 19, 2016 / Vol. 65 / No. 6 US Department of Health and Human Services/Centers for Disease Control and Prevention
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sleep were recorded in whole numbers by rounding 30 minutes
or more up to the next whole hour and dropping 29 or fewer
minutes. The age-adjusted prevalence and 95% confidence
interval (CI) of the recommended healthy sleep duration
(≥7 hours) was calculated by state and selected characteristics,
and adjusted to the 2000 projected U.S. population aged
≥18 years. For comparisons of prevalence between subgroups,
statistical significance (p<0.05) was determined by t-tests. All
indicated differences between subgroups are statistically signifi-
cant. Statistical software programs that account for the complex
sampling design of the BRFSS were used for the analysis.
Among 444,306 respondents, 11.8% reported a sleep duration
≤5 hours, 23.0% reported 6 hours, 29.5% reported 7 hours, 27.7%
reported 8 hours, 4.4% reported 9 hours, and 3.6% reported
≥10 hours. Overall, 65.2% reported the recommended healthy
sleep duration (age-adjusted prevalence=64.9%) (Table 1). The
age-specific prevalence of sleeping ≥7 hours was highest among
respondents aged ≥65 years (73.7%) compared with other age
groups. The age-adjusted prevalence of healthy sleep duration was
lower among Native Hawaiians/Pacific Islanders (53.7%), non-
Hispanic blacks (54.2%), multiracial non-Hispanics (53.6%),
and American Indians/Alaska Natives (59.6%) compared with
non-Hispanic whites (66.8%), Hispanics (65.5%), and Asians
(62.5%). Respondents who indicated they were unable to work
or unemployed had lower age-adjusted healthy sleep duration
prevalences (51.0% and 60.2%, respectively) than did employed
respondents (64.9%). The prevalence of healthy sleep duration
was highest among respondents with a college degree or higher
(71.5%). The prevalence was higher among married respondents
(67.4%) compared with those who were divorced, widowed, or
separated (55.7%), or never married (62.3%).
Prevalence of healthy sleep duration varied among states
and ranged from 56.1% in Hawaii to 71.6% in South Dakota
(Table 2). Most of the Great Plains states were in the upper
quintile for healthy sleep duration; states in the southeastern
United States and along the Appalachian Mountains tended
to be in the lower quintiles (Figure).
Discussion
This is the first published report to document state-based
estimates of self-reported healthy sleep duration for all 50
states and the District of Columbia. On average, 65.2% of
adult respondents reported a healthy sleep duration. The
geographic distribution pattern of low healthy sleep duration
prevalence is consistent with 2008 state prevalence patterns of
perceived insufficient rest or sleep among U.S. adults (7). The
lower healthy sleep duration prevalence in the BRFSS among
non-Hispanic black adults relative to non-Hispanic whites is
consistent with a previous nationwide 2007–2010 comparison
from the National Health and Nutrition Examination Survey
(NHANES) (8). The results also suggest that employment
and higher education might be determinants of healthy sleep.
A lower prevalence of healthy sleep duration was observed in
the southeastern United States and in states along the Appalachian
Mountains. This distribution is similar to geographic variations in
prevalence estimates for obesity (9) and diabetes (9) and death rates

Morbidity and Mortality Weekly Report
MMWR / February 19, 2016 / Vol. 65 / No. 6 139
US Department of Health and Human Services/Centers for Disease Control and Prevention
from heart disease§ and stroke.¶ Short sleep duration (<7 hours per
night) and other indicators of poor sleep health are associated with
greater insulin resistance, metabolic abnormalities, and weight gain
(5), which might then result in diabetes and adverse cardiovascular
outcomes. A sleep duration of ≥7 hours is associated with lower
prevalence estimates of cigarette smoking, leisure-time physical
inactivity, and obesity compared with a short sleep duration.**
Although unhealthy adults with chronic conditions might sleep
longer (2,3), little empirical evidence exists to indicate that long
sleep duration (≥9 hour per night) causes adverse conditions among
healthy adults exists (1).
TABLE 1. Age-specific and age-adjusted* percentage of adults who
reported ≥7 hours sleep per 24-hour period, by selected characteristics
— Behavioral Risk Factor Surveillance System, United States, 2014
Characteristic No.†% (95% CI)§
Total 444,306 NA
Unadjusted NA 65.2 (64.9–65.5)
Age-adjusted NA 64.9 (64.6–65.2)
Age group (yrs)
18–24 23,234 67.8 (66.8–68.7)
25–34 42,084 62.1 (61.3–62.9)
35–44 52,385 61.7 (60.9–62.5)
45–64 173,357 62.7 (62.2–63.1)
≥65 153,246 73.7 (73.2–74.2)
Sex*
Male 185,796 64.6 (64.2–65.0)
Female 258,510 65.2 (64.8–65.7)
Race/Ethnicity*
White, non-Hispanic 348,988 66.8 (66.4–67.1)
Black, non-Hispanic 33,535 54.2 (53.3–55.2)
Hispanic 29,044 65.5 (64.5–66.4)
American Indian/Alaska Native 6,862 59.6 (57.1–62.1)
Asian 8,313 62.5 (60.2–64.7)
Native Hawaiian/Pacific Islander 797 53.7 (47.2–60.0)
Multiracial, non-Hispanic 8,241 53.6 (51.5–55.7)
Other, non-Hispanic 1,943 62.0 (58.1–65.8)
Employment status*
Employed 220,751 64.9 (64.4–65.3)
Unemployed 19,300 60.2 (58.8–61.6)
Retired 130,478 60.9 (54.4–67.1)
Unable to work 31,953 51.0 (49.4–52.5)
Homemaker/student 37,393 69.5 (68.5–70.5)
Education level*
Less than high school diploma 33,833 62.5 (61.5–63.5)
High school diploma 125,462 62.4 (61.8–63.0)
Some college 120,814 62.4 (61.8–62.9)
College graduate or higher 161,088 71.5 (71.0–71.9)
Marital status*
Married 238,262 67.4 (66.9–67.9)
Divorced, widowed, separated 126,519 55.7 (54.5–56.9)
Never married 65,232 62.3 (61.5–63.2)
Member of unmarried couple 11,152 65.2 (63.3–67.1)
Abbreviations: CI = confidence interval; NA = not applicable.
* Age-adjusted to the 2000 projected U.S. population aged ≥18 years, except
for age groups.
† Unweighted sample of respondents. Categories might not sum to sample total
because of missing responses.
§ Weighted percentage and 95% CI.
TABLE 2. Age-adjusted* percentage of adults who reported ≥7 hours
sleep per 24-hour period, by state — Behavioral Risk Factor
Surveillance System, United States, 2014
State No.†% (95% CI)§
Alabama 8,335 61.2 (59.6–62.8)
Alaska 4,286 65.0 (62.9–67.0)
Arizona 14,437 66.7 (65.3–68.0)
Arkansas 5,067 62.6 (60.3–64.9)
California 8,660 66.4 (65.1–67.7)
Colorado 13,043 71.5 (70.5–72.5)
Connecticut 7,707 64.8 (63.2–66.5)
Delaware 4,153 62.4 (60.0–64.6)
District of Columbia 3,866 67.8 (65.4–70.2)
Florida 9,565 64.2 (62.7–65.7)
Georgia 6,164 61.3 (59.5–63.0)
Hawaii 7,110 56.1 (54.3–57.8)
Idaho 5,380 69.4 (67.4–71.2)
Illinois 5,023 65.6 (63.7–67.4)
Indiana 11,239 61.5 (60.2–62.8)
Iowa 7,976 69.0 (67.5–70.4)
Kansas 13,442 69.1 (68.1–70.1)
Kentucky 10,890 60.3 (58.7–61.9)
Louisiana 6,608 63.7 (62.2–65.2)
Maine 8,980 67.1 (65.6–68.6)
Maryland 12,171 61.1 (59.4–62.8)
Massachusetts 15,072 65.5 (64.2–66.8)
Michigan 8,275 61.3 (59.8–62.8)
Minnesota 16,049 70.8 (69.9–71.7)
Mississippi 4,043 63.0 (60.8–65.2)
Missouri 6,888 66.0 (64.2–67.8)
Montana 7,306 69.3 (67.5–71.0)
Nebraska 22,007 69.6 (68.5–70.7)
Nevada 3,649 63.8 (61.3–66.3)
New Hampshire 6,022 67.5 (65.7–69.4)
New Jersey 12,617 62.8 (61.5–64.2)
New Mexico 8,737 68.0 (66.3–69.5)
New York 6,641 61.6 (60.1–63.2)
North Carolina 7,034 67.6 (66.2–68.9)
North Dakota 7,635 68.2 (66.4–70.0)
Ohio 10,712 62.1 (60.5–63.6)
Oklahoma 8,237 64.3 (62.9–65.7)
Oregon 5,099 68.3 (66.4–70.1)
Pennsylvania 10,707 62.5 (61.1–64.0)
Rhode Island 6,243 63.3 (61.4–65.1)
South Carolina 10,636 61.5 (60.2–62.9)
South Dakota 7,270 71.6 (69.6–73.5)
Tennessee 4,966 62.9 (60.7–65.0)
Texas 14,950 67.0 (65.7–68.3)
Utah 14,719 69.2 (68.3–70.1)
Vermont 6,357 69.0 (67.4–70.4)
Virginia 9,225 64.0 (62.6–65.3)
Washington 9,874 68.2 (66.8–69.6)
West Virginia 6,050 61.6 (60.0–63.2)
Wisconsin 6,955 67.8 (66.1–69.5)
Wyoming 6,229 68.7 (66.5–70.8)
Median (50 states and DC) 444,306 64.9 (64.6–65.2)
Abbreviations: CI = confidence interval; DC = District of Columbia.
* Age-adjusted to the 2000 projected U.S. population aged ≥18 years.
† Unweighted sample of respondents.
§ Weighted percentage and 95% CI.
§ National map of heart disease death rates by county (http://www.cdc.gov/
dhdsp/maps/national_maps/hd_all.htm).
¶ National map of stroke death rates by county (http://www.cdc.gov/dhdsp/
maps/national_maps/stroke_all.htm).
** http://www.cdc.gov/nchs/data/hestat/sleep04-06/sleep04-06.htm.

Morbidity and Mortality Weekly Report
140 MMWR / February 19, 2016 / Vol. 65 / No. 6 US Department of Health and Human Services/Centers for Disease Control and Prevention
The findings in this report are subject to at least two limita-
tions. First, sleep duration was obtained by self-report and was
not corroborated by actigraphy (sensor-measurement of motor
activity), polysomnography (sleep study), other objective mea-
sures, or sleep journals. The overall estimate of 65.2% in the
2014 BRFSS adult population is slightly higher than the popula-
tion estimate of 60.1% from the 2007–2008 NHANES (2) and
slightly lower than the prevalence of 71.6% reported from the
2008–2010 National Health Interview Survey (NHIS).†† Some
variation might be a result of the different wording used by the
different surveys. Although BRFSS and NHIS both asked about
typical sleep duration in a 24-hour period, NHANES asked
how much sleep respondents typically get “at night on weekdays
or workdays.” Finally, institutionalized respondents were not
assessed in the present investigation, NHANES, or NHIS; if
institutionalized persons are more likely to have shorter sleep
durations because of chronic physical or mental conditions, then
the prevalence of ≥7 hours might be overestimated in the BRFSS
population. However, the relationships of healthy sleep with
sociodemographic characteristics, risk factors, and outcomes are
consistent with the other studies despite variations in definitions
of healthy or optimal sleep.
Based on recent recommendations for healthy sleep duration
(1), these findings suggest that, although almost two thirds of
U.S. adults sleep ≥7 hours in a 24-hour period, an estimated
83.6 million U.S. adults sleep <7 hours. Therefore, clinicians
might find routine discussion of sleep health with their patients as
well as pursuit of explanations for poor sleep health an important
component of providing health care. Healthy sleep duration in
adults can be promoted by sleep health education and behavior
changes, such as setting a pattern of going to bed at the same time
each night and rising at the same time each morning; making
sure that the bedroom environment is quiet, dark, relaxing, and
neither too hot nor too cold; turning off or removing televisions,
computers, mobile devices, and distracting or light-emitting
electronic devices from the bedroom; and avoiding large meals,
nicotine, alcohol, and caffeine before bedtime.§§ Insomnia
symptoms, such as trouble falling or staying asleep can usually be
resolved with improved sleep habits or psychological or behavioral
therapies (10). At present, no professional sleep organizations
have issued consensus statements or recommendations about the
efficacy or safety of either over-the-counter or prescription sleep
aids for improving sleep duration in the general adult population.
In addition, strategies to reduce risks associated with shift work
and long work hours include designing better work schedules.§§
Evaluation and monitoring of sleep might also be an important
function of health care professionals, including sleep specialists
(5). Keeping a 10-day sleep journal or diary about sleep times,
napping, and behaviors that affect sleep, such as exercise, alcohol
use, and caffeine consumption, might be helpful before discussing
sleep problems with a physician.¶¶
FIGURE. Age-adjusted percentage of adults who reported ≥7 hours
of sleep per 24-hour period, by state — Behavioral Risk Factor
Surveillance System, United States, 2014
68.8–71.6
67.1–68.7
64.1–67.0
62.2–64.0
56.1–62.1
DC
Summary
What is already known about this topic?
Short sleep duration (<7 hours per night) is associated with greater
likelihoods of obesity, high blood pressure, diabetes, coronary
heart disease, stroke, frequent mental distress, and death.
What is added by this report?
The first state-specific estimates of the prevalence of a ≥7 hour
sleep duration in a 24-hour period show geographic clustering of
lower prevalence estimates for this duration of sleep in the
southeastern United States and in states along the Appalachian
Mountains, which are regions with the highest burdens of obesity
and other chronic conditions. Non-Hispanic black, American
Indian/Alaska Native, and Native Hawaiian/Pacific Islander, and
multiracial populations report a lower prevalence of ≥7 hours
sleep compared with the rest of the U.S. adult population.
What are the implications for public health practice?
The determination that more than a third of U.S. adults report
sleeping <7 hours and findings of geographic and sociodemo-
graphic variations in low prevalence of healthy sleep duration
suggest opportunities for promoting sleep health. These
opportunities include sleep health education, reducing racial/
ethnic and economic disparities, changes in work shift policies,
and routine medical assessment of patients’ sleep concerns in
health care systems.
§§ National Institute of Occupational Safety and Health: review of the evidence
about risks associated with shift work and long workhours and strategies to
reduce these risks, including suggestions for designing better work schedules
(http://www.cdc.gov/niosh/docs/2015-115).
¶¶ http://www.cdc.gov/sleep.
†† http://www.cdc.gov/nchs/data/series/sr_10/sr10_257.pdf.

Morbidity and Mortality Weekly Report
MMWR / February 19, 2016 / Vol. 65 / No. 6 141
US Department of Health and Human Services/Centers for Disease Control and Prevention
1Division of Population Health, National Center for Chronic Disease Prevention
and Health Promotion, CDC.
Corresponding author: Anne G. Wheaton, AWheaton@cdc.gov, 770-488-5362.
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