As the world wakes up to racial disparities in healthcare, scientists are uncovering fundamental differences in wellness outcomes among people of differing races and ethnicities. Good health depends on high quality sleep — so why do some people get much less shut-eye than others?

Sleep is a vital component of health. People who sleep well enjoy a wide range of mental and physical benefits, from better concentration, sharper cognitive skills, and a stronger immune system to lowered chances of developing cardiovascular disease, depression, overweight, and obesity. Everyone needs an adequate amount of meaningful sleep to function well.

In this article, we assess the racial disparities in sleep duration and quality.

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According to the American Academy of Sleep Medicine, all adults need 7 hours of sleep every night. That’s challenging for many people, with at least one-quarter to one-third of Americans having trouble falling asleep or staying asleep at night, per 2020 data. And in a closer look at the statistics, racial and ethnic disparities emerge.

In a national survey of more than 400,000 Americans that the Centers for Disease Control and Prevention (CDC) conducted, also published in 2020, 34.8% of all U.S. adults revealed that they were not getting enough sleep. Results further showed that 43.5% of Black or African-American individuals had trouble sleeping, compared with 30.7% of white respondents.

Similar results have been borne out in other research over the past decade — and they point to a serious problem.

A growing body of research highlights racial disparities in sleep.

In 2022, scientists at the Yale School of Medicine published research that examined sleep trends among 429,195 U.S. adults between 2004 and 2018.

It found that Black respondents were consistently less likely to get 7 hours of sleep a day compared with their white counterparts and other people of color. Over the course of 15 years, that disparity worsened, with Black adults falling nearly 11 percentage points behind white respondents.

In fact, the study revealed that more than 41% of Black individuals were not getting enough sleep in 2018, versus 31% of white participants. This increase in sleep disparities serves to support similar findings from the National Health Interview Survey, a data collection arm of the CDC.

“The proportion of people reporting short sleep duration has increased across different racial and ethnic groups, widening the gap between Black and white individuals in recent years,” the Yale-led researchers affirmed.

Too much sleep

Black individuals were also more likely than other respondents to overly exceed the recommended amount of sleep, which researchers defined as more than 9 hours per night. Sleeping too much is not a positive event: The study linked it to potential health disparities.

“Both short and long sleep duration put individuals at increased risk of depression, reduced quality of life, cardiovascular disease, diabetes, and death, among other conditions,” the researchers wrote.

Sleep quality

Racial disparities exist not just in the amount of sleep, but in the quality, or “architecture,” of sleep. One study suggests that Black adults get less deep, slow-wave sleep than white adults do, and are more likely to report fatigue.

Other racial disparities

In most sleep studies, people of other races and ethnicities — not including Black and white individuals — who also experience sleep challenges, are often left out of demographic surveys, so there may be underrepresentation in the research.

A CDC sleep surveillance undertaking found that native Hawaiians and other Pacific Islanders are the least likely of any racial or ethnic group surveyed to sleep less than 7 hours a night, followed by Black adults.

Another study found that Hispanic individuals experience short sleep at levels approaching those of Black adults.

Poor sleep is often associated with poor health.

A 2021 study that compared the health of nearly 600,000 Americans of differing races and ethnicities over two decades found that Black individuals living in lower-income households were the most likely to report poor or fair health outcomes.

Sleep and chronic conditions

Many studies highlight the links between poor sleep, obesity, and heart conditions.

Regular sleep loss can:

  • disturb metabolic pathways
  • increase insulin resistance
  • affect the immune system
  • amplify hunger

It also drives up plasma levels of a pro‐inflammatory cytokine called interleukin 6 (IL-6), which is associated with a higher risk of:

The prevalence of sleep deprivation among Black adults may well account for some chronic conditions — such as high blood pressure, weight gain, and diabetes — occurring more frequently in this group of individuals.

Other systemic factors perpetuating health inequities, such as lack of access to quality healthcare, have been shown to also play a role in their health outcomes.

Health equity resources

Visit our dedicated hub for an in-depth look at social disparities in health and what we can do to correct them.

There are several reasons that Black adults may face more sleep challenges.

Discrimination

One reason may be that Black people frequently experience racial discrimination, which significantly affects their ability to sleep, according to the Yale-led study.

Research, such as a 2015 study involving further analysis of the Jackson Heart Study data, indicates that racial discrimination takes a particular toll on Black women. Study results found Black women had the greatest sleep deficit compared with white women. Black women also reported the highest occurrence of oversleeping. Research suggests socioeconomic stressors and health issues may also play a role.

Discrimination regarding socioeconomic status can also negatively affect sleep quality, according to studies. Researchers found that socioeconomic discrimination was associated with poor sleep quality in African American participants, but not white participants.

Other social experiences

Increasingly, researchers across multiple academic disciplines theorize that the sleep disparities that Black people experience are the result of:

  • historical stress
  • maltreatment
  • inequities in healthcare

Socioeconomic factors

It’s been theorized that genes and circadian rhythms play a role in sleep disparities. However, research has found that when people sleep in controlled environments, such as sleep labs, most of the disparities disappear.

A 2017 meta-analysis of 14 studies with more than 4,100 total participants compared sleep efficiency, total sleep time, and sleep latency in African Americans and European Americans. It found that disparities “were only present in community-based studies but not in studies where participants were examined in a laboratory setting, where time in bed is controlled.”

The finding once again suggests that cultural and social factors are the cause. Some of the following may further explain sleep disparities among Black adults:

  • Urban residence: Black people may be prone to “residential segregation,” which disproportionately locates them in urban or disadvantaged areas, “with increased crowding, noise, light, and air pollution,” all of which affect sleep. “Environmental and social features may modify sleep habits and contribute to poorer sleep quality, more sleep fragmentation, and less sleep opportunity,” relays a 2021 Chest study.
  • Work schedule: Research from The Shift Project, a survey group run by Harvard and the University of California at San Francisco, reveals that Black and Latinx Americans are disproportionately more likely to have jobs with unconventional hours, such as shift work, compared with their white peers. According to the American Academy of Sleep Medicine, shift work is known to disrupt sleep and can cause a condition caused shift work disorder.
  • Job strain: A 2022 analysis confirmed that people who experience discrimination have poorer sleep outcomes. Encountering racism at work can predict the onset of insomnia in Women of Color. For older Black men, insomnia is associated with feeling stressed or trapped by a job, reports a 2022 Duke University study.

Sleep apnea

Untreated sleep apnea may also be a contributing factor. The condition is much more prevalent among African American individuals than among their white counterparts. It also tends to be more severe, and is fatal more often.

A 2018 study that also further analyzed data from the Jackson Heart study showed that 95% of Black participants found to have sleep apnea had not been previously diagnosed.

Good sleep is essential to good health. But the research shows that Black Americans are less likely than white Americans or people of other races and ethnicities to get enough of it. And that may be affecting their health.

Reasons for poor sleep vary. But the research shows that Black Americans are more likely to report sleep deprivation (or less sleep) than most other racial/ethnic groups.