MONDAY, April 11 (HealthDay News) -- Young mothers tend to be heavier than their peers who don't have children, and they also consume more saturated fat, sugary beverages and total calories, a new study suggests.

Examining data from Project EAT (Eating and Activity in Teens and Young Adults), researchers from the University of Minnesota focused on the link between parental status, dietary intake, physical activity and body mass index (BMI) in 838 women and 682 men with an average age of 25.

While fathers were no heavier than their non-parenting peers, mothers had significantly higher BMIs, and both moms and dads exercised less frequently. But despite their greater intake of fat, sugar and calories, the young mothers also consumed as much fruit, dairy, whole grains and calcium as non-mothers, the study found.

Study author Jerica Berge said these mothers might be assuming more child-care duties than the dads, leading to the weight disparity. The aftereffects of pregnancy might also be a factor, she said.

"Maybe moms are taking on more responsibilities -- including cooking the food for the kids, with these high-fat choices," said Berge, an assistant professor of family medicine and community health. "In parenting, there are conflicting demands and tradeoffs. It could [also] be they're too tired at the end of the day and might not want to go to the gym."

The study is published online April 11 in the journal Pediatrics.

Project EAT, a longitudinal population study, followed young participants through three age points between 1998 and 2009, as they progressed into young adulthood.

Participants who became parents between the second and third follow-ups and had a child aged 5 or younger formed the parent group in the study.

Height and weight were self-reported, while a food-frequency questionnaire was used to assess the typical intake of such foods as fruit, dark green and orange vegetables, milk products and sugar-sweetened beverages over the prior year.

Young adults were also asked how many hours in a usual week they spent doing activities ranging from jogging or rollerblading to biking, skiing, dancing or bowling.

The fact that young mothers also consumed a similar amount of healthy foods than non-mothers may suggest they are trying to be good role models for their children, Berge said, although their use of higher-fat foods may stem from having less time to cook.

"I do think the study makes some good points about the struggles of being a young parent and balancing work and family life, and finding the time to plan physical activity," said Jen Brennan, clinical nutrition manager at Lenox Hill Hospital in New York City. "It's really easy to grab something unhealthy."

Health care professionals have many opportunities to intervene in this dynamic, Berge and Brennan said, because young children typically see pediatricians at least several times a year. Public health campaigns can also encourage healthy lifestyles among parents to set the stage for their children, they said.

"They already have time to talk about dietary intake and physical activity. There might be an opportunity to throw in, 'how does this work from a family perspective?'" Berge noted.

"Obviously, we need more research before we go off and change everything," she added. "We're not out there to make parents feel guilty about it -- it's more for us to step back and ask, how can we support them?"

More information

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