The need for something quick may be why half of total U.S. food expenditures today go to meals prepared outside the home.

Why fret: Studies suggest that the more you purchase fast food, the greater your girth. “This should come as no surprise because what is often ordered is mostly out-of-control portions higher in calories, fat, sugar, and salt than what would be served at home,” says Ayoob. Even shunning the Golden Arches for what you believe to be a smarter option could pack on pounds. Researchers reported in the Journal of Consumer Research that you are likely to underestimate the calories in a meal from a restaurant marketed as “healthier,” like Subway, than those in a meal from a perceived bad guy such as McDonald's. This mistake often leads to overeating when you purchase extra or bigger sides, suggest the study authors.

Parents should also take heed of a recent University of Minnesota study suggesting that adolescents who are part of families that rely on fewer than three purchased meals per week are more likely to consume milk and vegetables with meals and less prone to indulge in soda and chips at home.

Try this: Skip the drive-through and wipe the dust off your Joy of Cooking. “Preparing more home-cooked meals is all about planning and implementing time-saving strategies,” says Ponichtera, a mother of two. Take time during the weekend to create dinner menus for the coming week, with input from all family members, and make a detailed grocery list. This way you can get everything you need ahead of time and in one shot. Ponichtera also stresses the “cook once, serve twice” trick where you purposely make double the recipe and serve leftovers later — with different sides for variety. Need help with menu planning? Check out Delicious Living's healthy, affordable dinner recipes, or check out Ponichtera's Quick and Healthy Recipes and Ideas, Volume II (Small Steps, 2009).

When time becomes a premium, toss ingredients for stews or chilies into a slow cooker in the morning. “Always have a few homemade dishes that can be easily warmed up, such as lasagna, soups, and casseroles, in your freezer,” adds Ponichtera. You can also freeze food in lunch-size containers to take to work. On days when you do have time to cook, make salads and dressings, or bean, vegetable, and grain side dishes, so they will be ready accompaniments for the week's entrées. If possible, get your kids to help. “Involving children in the meal prep not only saves parents time but also teaches kids valuable cooking skills they might otherwise lack,” says Ponichtera.