Posted on November 30, 2022

Daylight Saving Time Sheds Light on Lack of Sleep’s Disproportionate Impact in Communities of Color

Jacqueline Howard, CNN, November 25, 2022

As the United States rolled back the clocks one hour this month to observe the end of Daylight Saving Time, many people got a bit more sleep than usual – but some not as much as others.

Growing evidence shows that lack of sleep and sleep disorders, such as obstructive sleep apnea, remain more prevalent in Black, Asian, and Hispanic or Latino communities, and these inequities can have long-term detrimental implications for physical health, even raising the risk of certain chronic diseases.

Meanwhile, Daylight Saving Time itself – enacted in the US to reduce electricity usage by extending daylight hours – has long been controversial in the United States.

The American Academy of Sleep Medicine, the Sleep Research Society and other medical groups have advocated for ending the practice, calling for the adoption of a permanent standard time that would not involve shifting forward each spring and falling back each autumn.

“Daylight saving time is associated with increased risks of sleep loss, circadian misalignment, and adverse health consequences,” Dr. Beth Malow, professor of neurology and pediatrics and director of the Vanderbilt University Medical Center Sleep Division in Nashville, said in a news release this month. {snip}

In March, the US Senate unanimously passed the Sunshine Protection Act, which would make Daylight Saving Time permanent across the country – meaning there would be no reverting to “standard time” from early November through mid-March – but the legislation would have to pass the House and earn President Joe Biden’s signature before becoming effective in November 2023.

Now, some sleep researchers worry about the potential effects that continuing to change standard time twice each year may have on sleep health inequities.

“Poor sleep is associated with a host of poor health outcomes, including obesity, hypertension, type 2 diabetes, cardiovascular disease and certain cancers, including of the breast and colon. Many of these health outcomes are more prevalent in the Black population,” said Chandra Jackson, a researcher and epidemiologist with the National Institute of Environmental Health Sciences, who has been studying racial and ethnic disparities in sleep.


As for the inequities seen in sleep health, it’s not that White adults don’t also experience a lack of sleep and its health consequences – but people of color appear to disproportionately experience them more, and that’s believed to be largely due to social systems in the United States.


Yet the racial and ethnic disparities in sleep duration appear to be getting worse across the United States, according to recent research by Caraballo-Cordovez, Jackson and their colleagues. Their study, published in April in the medical journal JAMA Network Open, found that among more than 400,000 adults in the US, between 2004 and 2018, the prevalence of short and long sleep duration was persistently higher among those who were Black and Hispanic or Latino. Short sleep is less than seven hours in a day, and long sleep is more than nine hours.

Although there was a significant increase in the prevalence of insufficient sleep across all groups during the study period, the prevalence of short sleep increased 6.39 and 6.61 percentage points among Black and Hispanic or Latino adults, respectively, compared with 3.22 percentage points among White people.


Many social and environmental determinants of health – including living conditions or work schedules that don’t support sleep – may emerge, at least in part, from historical and persistent forms of structural racism, which Jackson considers as the “totality of ways in which societies foster racial discrimination through mutually reinforcing systems of housing, education, employment, wages, benefits, credit, media, health care and criminal justice.”

Jackson added that she often reflects on how the shooting death of Breonna Taylor in Louisville in March 2020 and the shooting of George Floyd’s 4-year-old grandniece in Houston on New Year’s Day both happened when they were asleep – and how systems of structural racism in the US can cultivate conditions that make such incidents more likely to happen in Black communities. {snip}