Strategic Communications and Marketing News Bureau

Long work hours for moms mean less sleep, higher BMI’s for preschoolers

CHAMPAIGN, Ill. – The majority of preschoolers may not be getting the amount of sleep they need each night, placing them at higher risk of being overweight or obese within a year, according to a new study.

Published online by the journal Sleep Medicine, the study investigated links between mothers’ employment status and their children’s weight over time, exploring the impact of potential mediators, such as children’s sleep and dietary habits, the amount of time they spent watching TV and family mealtime routines.

“The only factor of the four that we investigated that mediated the relationship between maternal employment status and child obesity was how much sleep the child was getting each night,” said lead author Katherine E. Speirs, a postdoctoral research associate in human and community development at the University of Illinois.

Speirs and co-authors Janet M. Liechty and Chi-Fang Wu for one year followed 247 mother-child pairs from the STRONG Kids study. A health awareness initiative for families that focuses on preventing child obesity, the study is coordinated by the university’s Family Resiliency Center.

The children, who ranged from 3 to 5 years old, were weighed, measured and had their body mass index calculated at the outset of the study and again one year later.

At the second weigh-in, 17 percent of the preschoolers were overweight and 12 percent were obese, according to BMI-for-age growth charts.

Sixty-six percent of the mothers in the sample were employed full time, defined as working 35 hours or more per week. Another 18 percent of the women were employed part time, or 20 to 34 hours per week.

Children whose mothers worked full time got fewer hours of sleep than peers whose mothers worked less than 20 hours per week. The children of women who worked full time also tended to have higher BMIs at the second weigh-in.

Just 18 percent of the preschoolers in the sample were getting the 11 to 12 hours of nightly sleep recommended by the National Heart, Lung and Blood Institute, the researchers found.

On average, the children were getting about 9.6 hours of nighttime sleep. Each additional hour of nighttime sleep that a child obtained was associated with a 6.8 percent decrease in their BMI at the second weigh-in, the researchers found.

“We looked at nighttime sleep in particular, because studies show that the amount of nighttime sleep matters for regulating weight,” said Liechty, a professor of medicine and of social work.

“We think that it might be the more hours that mothers are working, the less time they have, and there may be some sort of tradeoff going on, ‘Do I spend quality time with my child or do we get to bed early?'” Speirs said. “And then in the morning, when mothers leave for work, their children also wake up early to get to day care.”

How much sleep is enough?

Age Recommended hours

of daily sleep

Newborns 16-18
Preschool-aged children 11-12
School-aged children At least 10
Teens 9-10
Adults, including the elderly 7-8

Source: National Heart, Lung and Blood Institute

Mothers whose children were enrolled in 32 licensed day care centers in Central Illinois were recruited for the study. Sixty-six percent of the women had college degrees; about a third had household incomes under $40,000 a year, and just over half the sample had household incomes under $70,000 a year.

“The challenges of ensuring that children obtain adequate sleep may be even greater for low-income women, who often hold multiple jobs or work rotating shifts or nonstandard hours,” Speirs said.

“There are lots of characteristics about mothers’ employment that are really important to help us better understand the relationship between mothers’ employment status and child obesity, such as whether women are working part time voluntarily or involuntarily, or scheduled or nonscheduled hours,” said Wu, a professor of social work.

The authors are exploring some of these characteristics and possible links with child obesity in a related study, which is underway.

To reach Katherine E. Speirs, call 217-300-4487; email kspeirs@illinois.edu.
Janet M. Liechty, call 217-265-0577; email jliechty@illinois.edu.
Chi-Fang Wu, call 217-244-5222; email cfangwu@illinois.edu.

The paper, “Sleep, but not other daily routines, mediates the association between maternal employment and BMI for preschool children,” is available online from ScienceDirect

Read Next

Life sciences Portrait of the research team posing together.

Minecraft players can now explore whole cells and their contents

CHAMPAIGN, Ill. — Scientists have translated nanoscale experimental and computational data into precise 3D representations of bacteria, yeast and human epithelial, breast and breast cancer cells in Minecraft, a video game that allows players to explore, build and manipulate structures in three dimensions. The innovation will allow researchers and students of all ages to navigate […]

Arts Photo of seven dancers onstage wearing blue tops and orange or yellow flowing skirts. The backdrop is a Persian design.

February Dance includes works experimenting with live music, technology and a ‘sneaker ballet’

CHAMPAIGN, Ill. — The dance department at the University of Illinois Urbana-Champaign will present February Dance 2025: Fast Forward this week at Krannert Center for the Performing Arts. February Dance will be one of the first performances in the newly renovated Colwell Playhouse Theatre since its reopening. The performances are Jan. 30-Feb. 1. Dance professor […]

Honors portraits of four Illinois researchers

Four Illinois researchers receive Presidential Early Career Award

CHAMPAIGN, Ill. — Four researchers at the University of Illinois Urbana-Champaign were named recipients of the Presidential Early Career Award for Scientists and Engineers, the highest honor bestowed by the U.S. government on young professionals at the outset of their independent research careers. The winners this year are health and kinesiology professor Marni Boppart, physics professor Barry Bradlyn, chemical and biomolecular engineering professor Ying […]

Strategic Communications and Marketing News Bureau

507 E. Green St
MC-426
Champaign, IL 61820

Email: stratcom@illinois.edu

Phone (217) 333-5010