There are many reasons childhood obesity is on the rise. Among them: Children are less active than they were a generation ago and advertising bombards children with messages that make fast food, sugary sweets and fatty foods appealing. Then with many parents working full time and children involved in after-school activities, families often eat processed, easy-to-prepare, high-calorie foods, or eat high-calorie fare at fast-food restaurants.

It's easy for parents to give in to the culture's current tendency toward poor eating habits. When kids pout or throw a tantrum for a sugary cereal because its box contains an advertised glitzy toy, it's the parenting path of least resistance to buy the cereal. It's upsetting and embarrassing for parents to deal in public with the negative emotions of children when they have been told "no" to such a purchase. For the long-term health of your children, though, it's better to hold to your "no." If you can't, buy the box, give the toy and throw out the sugary cereal.

It's between ages 3 and 8 that parents exert the most influence over their children's lifelong eating habits. During these years, children's tastes and interests expand; bad and good eating habits begin to form and solidify.

With this fact comes bad news and good news. The bad news is that throughout these formative years the influence from the media enters into their lives. The good news is that parents can counter the messages that children hear from TV advertising with their own messages.

When the begging for bad food begins, repeat in monotone your own versions of these lines: "Our family doesn't eat fried foods." "I can't buy that cereal; it's not good for you." "I don't buy or drink soda." "That's a processed food; I won't buy it." "Our family doesn't eat at fast-food restaurants."

It's important to realize what you can and can't control about your children's food intake.

You control the food you bring home and put on the table, but your children control what they swallow. With that information in mind, establish this approach to mealtime: Everyone makes his or her own meal with the food that Mom or Dad put on the table. This means that you offer foods each meal you know your children will like and eat, and then offer new food items to try. With pleasant mealtime conversation, usually everyone eats what he or she needs. Resist trying to convince, negotiate or coerce your child into eating.

Some do's and don'ts:

• Do coach your child as he or she eats: "Now focus on your tummy; is it full or are you still hungry?"

• Do talk up the good, healthy foods you love: "Boy, that was a good apple!"

• Do serve new foods but realize that it might take two weeks before a child tries it.

• Do teach about nutrition; don't lecture but instead offer information in sound bites: "Whole-wheat bread is better for you than white bread."

• Do explain out loud about your own eating decisions: "I'm only eating one slice of pizza. I'm full."

• Don't call your child a "picky eater." Such labels are difficult to shed.

• Don't think because a child rejects a food once that he'll always reject it.

• Don't involve your children in your bad eating habits. If you're an ice cream-aholic, eat your bowl of ice cream when your children are in bed.

• Don't say when your child is emotional and upset, "You're sad? Here's a bowl of ice cream; you'll feel better soon."

• Don't offer food as a reward for good behavior.

Although your children may whine for junk food today, they'll thank you in years to come when they're healthy and not fighting obesity.

For more information, read "The American Academy of Pediatrics Guide to Your Child's Nutrition: Making Peace at the Table and Building Healthy Eating Habits for Life," edited by William Dietz, M.D., Ph.D., F.A.A.P., and Loraine Stern, M.D., F.A.A.P.

Jan Faull, a specialist in child development and behavior, answers questions of general interest in her column. You can contact her at janfaull@aol.com or Jan Faull, c/o Families, The Seattle Times, P.O. Box 70, Seattle, WA 98111. More columns at www.seattletimes.com/columnists