Reducing Obese Moms' Sitting Time Lowers Fat Mass in Newborns

Becky McCall

October 04, 2019

BARCELONA, Spain — Improving diet, increasing physical activity, and reducing sedentary time among obese pregnant women seems to have a knock-on effect on their babies, who were born with lower fat mass than the offspring of women in control groups, a new analysis of the Vitamin D and Lifestyle Intervention study for gestational diabetes prevention (DALI) trial has shown.

Mireille van Poppel, PhD, from the Institute of Sport Science, University of Graz, Austria, presented the results at the European Association for the Study of Diabetes (EASD) 2019 Annual Meeting.

Of interest, "It was the sedentary behavior that seems to be responsible for the change in neonatal body composition [according to leptin and skinfold measurements], not the reduction in gestational weight as many people might have thought," remarked van Poppel in an interview with Medscape Medical News.  

She stressed that this is one of the first reports of a link between the two and the finding about sedentary time provides an important message for public health.

"Sitting less, getting out of a chair, and pottering around the house can be effective in terms of health benefits, which might be easier to do, especially in pregnancy, than having to be more active by going to a fitness center or gym," she said.

Cuilin Zhang, MD, PhD, National Institutes of Health, Bethesda, Massachusetts, who has a special interest in the determinants and health consequences of diabetes and obesity, commented on van Poppel's work.

"Identifying the risk factors for...obesity and cardiometabolic early life or in utero may shed new light" on how these can best be prevented, she observed.

"Greater attention has been paid to the promotion of physical activity and a healthful diet during pregnancy, but less for the reduction in sedentary time," remarked Zhang.

"Findings from the DALI study are among the first...demonstrating that reducing sedentary time during pregnancy can lower blood leptin levels, and potentially reduce neonatal fat mass, which may have lifelong benefits for both pregnant women and their offspring's health," she stressed.

Neonatal Outcomes of the DALI Trial

The DALI study tested different strategies to prevent development of gestational diabetes among obese pregnant women (body mass index ≥ 29 kg/m2) from nine EU countries. Participants were assigned to one of eight intervention arms, which included advice on healthy eating and physical activity, alone or in combination, vitamin D administration or not, and placebo/control groups.

"We saw an improvement in gestational weight gain in the group that received advice on diet and physical activity, with a reduction of over 2 kg at 35-37 weeks of pregnancy compared to controls," said van Poppel, reviewing the results originally reported in 2016. However, this did not lead to a significant reduction in gestational diabetes.

Nor did vitamin D supplementation have any effect on the risk of gestational diabetes, as reported earlier this year.

The latest DALI analysis went on to examine whether the lifestyle changes were associated with differences in neonatal outcomes.

"We know that maternal obesity and gestational weight gain affect the child, who has a higher risk of developing obesity later in their life. One obvious solution is to intervene during the pregnancy to try and prevent the negative effects of maternal obesity on adiposity in the child," said van Poppel.

Among 436 women, improvements were seen in the amount of physical activity in the group that received counseling on this, compared with controls, and there were improvements in diet and a reduction in sedentary behavior in the women who received advice on both healthy eating and physical activity, she said.

But there was no difference in birthweight, nor any significant change in risk of large-for-gestational age babies, because of these interventions.

"Birthweight is a poor outcome because it doesn't tell you anything about body composition, which is why we wanted to look at neonatal skinfolds," said van Poppel, explaining the rationale for their further investigation.

Leptin Levels Linked to Amount of Time Sitting

On further analysis, the researchers found a significant reduction in skinfold thickness, and in body fat, of neonates of women who received combined counseling (on diet and physical activity) compared with controls, van Poppel reported at EASD.

The results were also recently published in Diabetologia (2019;62:915-925).

The difference was 1.8 mm, equating to an 8% reduction (P = .03), in skinfold thickness, and a similar reduction in body fat of 9% (P = .04 vs controls) even after adjusting for confounding factors.

A reduction in cord blood leptin was also seen in neonates born to mothers in the combined intervention group (P = .03) and women in the physical activity alone group (P = .05), compared with those assigned to usual care.

Leptin is a marker for neonatal adiposity that is independent of skinfold measurements.

And when the researchers analyzed this further, they found that sedentary time was the parameter of most interest.

Reduced sedentary time, but not differences in gestational weight, mediated intervention effects on leptin in both the healthy eating plus physical activity and physical activity alone groups.

"The more women sat, the higher the neonate's cord blood leptin level," explained van Poppel.

However, more research is needed to understand the implications of the findings for future adiposity and diabetes risk of the offspring, she concluded.

Van Poppel and Zhang have reported no relevant financial relationships.

EASD 2019 Annual Meeting. Presented September 19, 2019.

For more diabetes and endocrinology news, follow us on Twitter and Facebook.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.