Being overweight and ignoring the body's signals to get some sleep at night can have particularly negative health effects among men and women, according to a new study from Oregon Health & Science University.
The study was published this week in The Journal of Clinical Endocrinology & Metabolism.
“This study reinforces the importance of good sleep habits, such as going to bed when you're tired and avoiding screen time at night, which can help promote overall health.”
Brooke Schafer, PhD, lead author and postdoctoral researcher in the Sleep, Chronobiology and Health Lab in the OHSU College of Nursing
The study recruited 30 people, evenly split between men and women, all with a BMI of 25 or above, putting them in the overweight or obese category.
“Obesity and cardiometabolic disease are growing public health concerns,” Schafer said. “Our study shows that disruption of the circadian clock may have adverse health effects in people who may already be experiencing adverse health effects due to their weight.”
In a sleep lab on OHSU's Markham Hill campus, generally healthy participants collected saliva samples every 30 minutes late into the night to determine when their bodies naturally began producing a hormone called melatonin, which is generally thought to initiate the process of falling asleep, and whose onset varies depending on each individual's internal biological clock.
Participants then went home and recorded their sleep habits for the next seven days.
The researchers assessed the difference between each participant's melatonin onset and average sleep time and divided participants into two groups: those with narrow windows, meaning a short time between melatonin onset and sleep, and those with wider windows, meaning a longer time between melatonin onset and sleep. Those with narrow windows were shown to stay up later than their body clocks would suggest, and generally tend to be in poorer health.
A new study has identified a range of potentially harmful health behaviours in people who went to bed closer to the onset of melatonin production.
They also found important differences between men and women: The men in this group had higher levels of abdominal fat and fatty triglycerides in their blood, as well as a higher overall metabolic syndrome risk score, compared to men with better sleep quality, while the women in this group had higher overall body fat percentage, blood sugar levels, and resting heart rates.
“It's really surprising that these differences manifest in different ways by gender,” said Dr. Andrew McHill, an associate professor at the Oregon Health & Science University School of Nursing, Oregon Health & Science University School of Medicine and Oregon Health & Science University and senior author of the paper. “We sometimes think about this in academic medicine, but it's not the same for everyone.”
The next phase of the study will identify gender-specific differences in groups that experience more profound changes in sleep patterns, such as night-shift workers.
“We want to identify possible interventions to maintain the health of this important core group of the workforce,” Schafer said.
sauce:
Oregon Health & Science University
Journal References:
Shafer, BM, et al. (2024). Circadian rhythms, cardiometabolic disease, and gender differences in overweight/obese adults. Journal of Clinical Endocrinology and Metabolism. doi.org/10.1210/clinem/dgae580.
