Babies who sleep longer at night and with fewer breaks are less likely to be overweight in the first six months of life, according to a study published in the journal SLEEP. While research shows only a link – not a causal link – between sleep and baby weight, the findings show that newborns can reap some of the same health benefits that others derive from consistent, quality eye closure.
The study emerged from the Rise and SHINE study, which analyzes the ways in which sleep can affect a newborn’s growth and development. The five-year study is supported in part by the National Heart, Lung and Blood Institute (NHLBI), part of the National Institutes of Health.
“What’s particularly interesting about this study is that the association with sleep obesity that we see throughout life occurs in early childhood and can predict future health outcomes,” says Dr. Mariska K. Brown. , director of the National Center for Sleep Disorders Research, located at NHLBI. Brown noted that numerous studies have shown links between good sleep and improved health. For children, this includes a reduced risk of developing obesity and diabetes, while supporting development, learning and behavior.
In the current study, researchers looked at 298 newborns and found that for every hourly increase in nighttime sleep, measured between 7 p.m. and 8 a.m., babies were 26 percent less likely to become overweight. Similarly, with each decrease in nocturnal awakening, they are 16% less likely to become overweight.
To conduct the study, the researchers partnered with mothers who gave birth to a baby at Massachusetts General Hospital between 2016-2018. Unlike other sleep studies of infants that rely on parental reports, the researchers used ankle activation clocks to objectively track nocturnal movement, capturing data for three nights in the first and six-month periods.
Parents also keep diaries of the baby’s sleep and share information about activities that could affect each baby’s sleep or weight, such as how often they are breastfed or whether the baby has eaten solid foods before the age of four months.
To estimate weight, the researchers used age and gender-specific growth tables from the World Health Organization. A baby is considered overweight if he is at or above the 95th percentile for weight and length. In reviewing the data, the researchers also took into account maternal health considerations and sociodemography.
Susan Redline, MD, author of the study, who is also a senior physician at Brigham and Women’s Hospital and a professor of sleep medicine at Harvard Medical School, said her colleagues were intrigued by the idea of studying the links between sleep patterns. baby and weight. Basically, they wanted to know what happened when babies progressed from sporadic sleep patterns, common in early childhood, to a longer sleep pattern at night. They found that babies who switched to a stable night’s sleep – an average of 8.8 hours a night by the end of the study – and who had fewer nocturnal awakenings were less likely to be overweight in the first six months. .
After the first month, the researchers found that 30 of the babies (10.3% of the sample) were overweight, although most – 21 – reached a normal weight at six months. At the end of the six-month assessment, 26 babies (8.8%) were overweight, including 15 who had not previously been overweight.
Researchers suspect that several factors may explain these results. Some parents can soothe infants who have trouble sleeping by providing milk or introducing them to solid foods. Also, if a baby did not get enough high-quality sleep at night, it could feel hungry and tired the next day – which leads to more feeding and less exercise, which in turn can contribute to the baby’s weight. . Although additional data are needed to monitor these potential links and any other influencing factors, data to date suggest that adequate and consolidated sleep can be a powerful tool in reducing the risk of obesity at an early age.
This study emphasizes the importance of sleep health not only for adults but also for people of all ages. Parents should consult with their pediatricians about best practices for promoting healthy sleep, which may include maintaining consistent sleep schedules, providing a dark and quiet sleeping space, and finding the most appropriate ways to respond to wakefulness. the baby. “
Susan Redline, author of the study
National Institutes of Health
Reference in the magazine:
Lee, X., and others. (2021) Longitudinal relationship of sleep, assessed by actigraphy, with physical growth during the first 6 months of life. Sleep. doi.org/10.1093/sleep/zsab243.