Though the reasons are not clear, researchers have discovered that adults whose households include children have worse diets -- that is, higher in saturated fats -- than adults who do not live with kids.

Their findings, based on data from a US government health survey, are scheduled for publication in the Journal of the American Board of Family Medicine in January.

This research departed from most other studies of family dietary habits by examining the influence of children on adults instead of the other way around, noted the study's primary author, Helena Laroche, MD, of the University of Iowa's Roy J. and Lucille A. Carver College of Medicine.

"The study doesn't prove that the presence of children causes adults to eat more fat," she said. "People living with children may have different eating habits for many reasons. However, an important implication of the study is that healthy changes in eating need to focus on the entire household, not just individuals. Healthcare professionals must also help families find ways to fit healthy foods into their busy lifestyles."

Laroche and colleagues at the University of Michigan Health System analyzed questionnaires given to 6,600 adults ages 17 to 65 living with and without children under age 17. The participants came from a variety of racial, ethnic and economic backgrounds. Trained nutritionists asked detailed questions about their dietary habits and those of other family members.

Compared to adults living without children, adults living with children ate an additional 4.9 grams of fat daily, including 1.7 grams of saturated fat, the study team found. Adults with children in the home were more likely to eat cheese, ice cream, beef, pizza and salty snacks.

"Adults with children in the home ate more of those snacks and other foods that we considered convenience foods," Laroche 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. Once these foods are in the house, even if bought for the children, adults appear more likely to eat them."

Saturated fat has been linked to heart disease. Foods high in saturated fat include butter, lard, coconut oil, cottonseed oil and palm kernel oil; dairy products, especially cream and cheese; meats; and a variety of prepared foods.