Adults living with children tend to eat more fat than grown-ups in kid-free homes, consuming as much saturated fat each week as found in an individual-size pizza, a new study suggests.

It may not exactly be the kids' fault, but household cupboards are more likely to be stocked with high-fat convenience foods like cookies, cheese, peanuts and processed meats when children are around, the researchers said.

"These dietary choices may be due to time pressures, advertising aimed at children that also includes adults, or adults' perception that children will eat only hot dogs or macaroni and cheese," said study author Dr. Helena Laroche, who works in internal medicine and pediatrics at the University of Iowa College of Medicine.

"Once these foods are in the house, even if bought for the children, adults appear more likely to eat them," she said.

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Laroche cautioned that the report "doesn't prove that the presence of children causes adults to eat more fat," but shows that people living with children may have different eating habits for many reasons.

Laroche and University of Michigan researchers examined data from the federal government's National Health and Nutrition Examination Survey. The researchers scoured detailed food questionnaires given to 6,600 adults living with and without children under age 17. The survey reviewed what the adults ate over a 24-hour period.

Adults living with children ate almost 5 more grams of fat each day, for a total of more than 91 grams, compared to 86.5 grams for adults not living with children, according to the study. That included nearly 2 grams more of saturated fat daily, the kind linked to heart disease, or about 12 grams of saturated fat per week — an amount equal to a 6-inch, personal size pepperoni pizza.

An adult eating a 2,000-calorie diet should consume less than 65 grams of total fat a day, including less than 20 grams of saturated fat, according to the U.S. Department of Agriculture.

Tracey Adamowski, a 39-year-old mother of two from West Des Moines, Iowa, knows about the struggle to eat healthier foods. She recently lost 30 pounds on Weight Watchers, but said trips to the grocery store usually revolved around her kids' tastes.

"You buy cookies and you buy snack foods and you buy hot dogs and you buy canned raviolis and all this, and now that's there when you open the cabinet," said Adamowski, who sent her son off to college last year and has a 13-year-old daughter at home.

Before adopting healthier eating habits, Adamowski stocked the cupboards with those foods, picked at her kids' leftovers in restaurants, cooked easy-to-fix hot dogs or grabbed fried fast-food for dinner.

"It's very easy to go through a drive-thru, especially when that's the only way you can eat together as a family sometimes," said Adamowski, who does about 30 hours a week of volunteer work.

Jam-packed schedules are a problem for many families, said Susan Mitchell, a registered dietitian, author and nutrition expert who hosts a radio program in Orlando, Florida.

"Adults pick up foods that the kids want, so the kids end up driving the nutrition habits of the household instead of parents," she said. "Parents then eat what they eat, and everyone gets a fatty diet."

She recommends families adopt one or two small changes at a time — such as cutting back on the number of times each week they eat fast food, or adding fresh fruit to their diet. That way, there will be less rebellion to new, healthy habits.

"Everyone in the family needs to get on board with healthy eating, and it needs to be promoted as a positive move," she said.

What's unique about the University of Iowa-led study, Laroche said, is that it examines how children's eating habits affect adults. Most other studies look at adult habits and their influence on children.

Rachel Tolbert Kimbro, a medical sociologist at the University of Wisconsin in Madison, said it is an important study that shows that giving children access to healthy foods can also benefit their parents' health.

"It's important for busy parents to recognize the effect that having children in the household can have on their diets — and that by keeping high-fat food around in the house that they believe their children want, they may be putting their own health at risk," she said.

The study, which got funding from the Robert Wood Johnson Clinical Scholars Program and the National Institutes of Health, appeared this month in the online edition of the Journal of the American Board of Family Medicine.

Now, Laroche said, she wants to study the many reasons adults are influenced by children's eating habits.

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