When Jocelyn Malamy’s daughter, Eve, was 2 years old, she says the only thing the toddler wanted to eat at mealtime was cheddar cheese “by the handful.” Now 7, Eve likes only six or seven different meals, and that’s a triumph in itself.

“It took us a while to get here,” says Malamy, of Chicago. It took work to expand Eve’s diet, but her mom knew it was a battle worth fighting.

“You want to feed your kid healthy food. It’s a primal need to feed them good food and have them eat it.”

Despite her selectiveness, Eve’s diet is healthy overall, and she is a vibrant 7-year-old, full of energy. She’s mostly vegetarian, aside from one particular brand of apple chicken sausage she likes. She even loves broccoli. But everything she eats is won through a series of negotiations.

“It’s a struggle. It’s constant stress,” Malamy says. “When she doesn’t want to eat, it can take hours. It has to be games and threats and rewards—lots of stress several times a day.”

Whether kids eat very few things or eat everything in sight, every parent worries about their child’s diet. They’re fighting for apples and milk in the face of Doritos commercials and a Starbucks on every corner. With one-third of all children and adolescents falling into the obese category, the struggle is real. And despite all the news stories and all the public service campaigns, the problem just keeps getting bigger.

“About 3 million kids are severely obese right now in the U.S.,” says Dr. Elizabeth Prout Parks, a physician nutrition specialist and childhood obesity researcher at The Children’s Hospital of Philadelphia.

“Severely obese—that’s the next level. Those are the sickest kids who are the most likely to have type 2 diabetes and other health issues.”

Without intervention, many of these severely obese kids will grow up into obese adults, and could suffer a whole host of health problems because of their weight. To avoid this dire fate, parents need real solutions for building lifelong healthy eaters, simple enough to do every day, yet effective enough to last a lifetime. With consistency and an understanding of how your child thinks about food, you can serve up the habits that will have them eating healthy for life.

Model Behavior

So how do you help a child understand how to eat healthy, and steer them toward the best choices? Explaining the concept of nutrition generally doesn’t work until middle school because kids aren’t “fully rational,” says dietitian Kathryn Hoy, manager of the Cornell Center for Behavioral Economics in Child Nutrition Programs in Ithaca, N.Y.

“You can’t say, ‘Johnny, don’t eat that because you are going to be obese long term,’” Hoy says. “Kids don’t know what obese is.”

As kids mature, it’s important to help them develop a love of healthy foods and understand how those foods strengthen and energize the body, says Monica Paduch, a pediatric dietitian at LeHigh Valley Health Network in Allentown, Pa.

Paduch recommends sitting children at a table during meal times so they can focus on eating, rather than playing or watching TV at the same time. Have the whole family eat together so children can learn and mimic the positive habits of their parents and older siblings. Have consistent meal times and avoid snacking before meals, Paduch says. Drink water before and during a meal, but save the milk for the end since it can be filling. Don’t be too thrown if they refuse a meal, but don’t let it be an excuse for them to grab junk food later. Be ready with a healthy snack.

“If the child doesn’t want to eat (dinner), that’s fine. But when 30 minutes later they say they are hungry, bring out the snack,” she says.

Modeling healthy habits is key, so incorporate fruits and vegetables into your own diet as well as your child’s, Parks says. Be patient. It takes time to get children to eat new foods. It can take as many as 20 introductions to get a young child to like something new.

It’s understandable that you may want to give up if your 3-year-old has a meltdown over Brussels sprouts, Hoy says. But persistence pays.

“There has to be some degree of perseverance of the parents,” Hoy says.

You can train your child to like vegetables, Paduch says, but you have to commit to the idea, and continually reinforce the foods.

“A lot of families give up after three or four times and think they just don’t like peas,” she says. “It’s not true.”

Teaching good tastes

Toddler: Playful eaters

During their first few years, children explore the world of foods, especially with their fingers, Paduch says. Encourage them—it’s one time in life when it’s OK to play with your food.

“Allowing that exploration is important for developing eating habits,” she says.

Also make sure to give them appropriate serving sizes. Young children don’t need that much food—usually one tablespoon of each food for each year of age is enough. So, if you’re serving a 5-year-old chicken, potatoes and green beans, five tablespoons of each will suffice. Children tend to eat only until they are full, so believe them when they tell you they’re full. Don’t make them finish. If they consistently leave food on their plate, you likely are giving them too much.

Toddlers will eat mostly anything, though whole grains are often unpopular, Paduch says. “Some toddlers also dislike different textures, like squishy seeds,” she says.

To introduce new foods, Paduch recommends making them look fun. You can stick to the classics, like spreading peanut butter on celery and dotting it with raisins to make ants on a log. Or surf the Web for new fun food recipes and ideas—check out Pinterest and recipe sites like FoodNetwork.com. And you don’t have to go it alone. Make it a family project, and let toddlers help make their own snacks.

Kids like things that are kid-sized, so chop up food in smaller pieces. It helps to cut the food into fun shapes, Parks says.

Make healthy options more attractive by filling ice cube tray compartments with cut fruits and veggies for their own little snack tray to eat from.

Try introducing new foods with foods they already like, and encourage them to take a bite. Serve up a bit of brand new broccoli alongside well liked corn, and just try to let things happen naturally.

“Don’t push it, don’t fill the plate,” Parks says. “Don’t make the new food the only thing there is. That puts a lot of pressure on them.”

Preschool to Grade School: expanding appetites

As they get older, children’s diets expand, and they also start to become more aware of and more affected by what their friends eat, Paduch says.

“They are more willing to try foods, but more often go into negative eating habits because they see what their peers are eating. Sometimes it’s not always the best beliefs or habits,” she says. “‘My friends are eating chips. Why am I eating an apple my mom packed?’”

Children this age often prefer sweet foods and tend to avoid whole grains, Paduch says, something that is evident in their choice of cereals—a favorite food among this age group. This is the time to encourage them to eat high-fiber cereals instead of sugary ones, and hope the habit will stick.

She encourages giving them a dose of reality, and playing to their sense of wanting to feel grown up.

“Tell them they need to be a big kid and step up to the plate,” she says. “It’s not going to hurt them to have a half serving of new food, and I try to ask them to eat that first, then eat the food they like.”

It also helps to make foods look fun and taste exciting, Paduch says. Pair a yogurt dip with bananas, or guacamole with pita bread. Cut sandwiches into fun shapes. Top oatmeal with raisins or other dried fruit. Or, come up with a fun name for the food—it can be as simple as naming it after your kid, like Annie’s Apple Slices.

Preteen to Teen: Taste Buds

The teen years are when many kids’ diets go off the rails. Paduch says many preteens and teens tend to gravitate toward salty and sweet snacks. Often they don’t eat enough vegetables or whole grains.

Many teens stop drinking milk, but it’s important they get enough calcium during this time, because the body absorbs less after age 20, Paduch says.

One way to encourage preteens and teens to eat healthy and try new foods is to allow them to choose a healthy meal, go shopping for food and have them cook it with guidance, Paduch says. Teens need to learn how to read recipes and cook.

“If they help make the salad and put together the entreé, they start to buy into it,” she says. “One day they have to do it themselves.”

It’s also especially important to have healthy snacks in the house for rapidly growing teens so they make good choices when they come home hungry. Stock up on baby carrots, clementines, and almonds and other protein-rich nuts. Keep chips and cookies for a special occasion.

“Treats are OK every now and then, but we don’t want to feed hunger with treats,” she says. “Try not to use treats as rewards, and, no matter how old, be a role model.”

During the preteen and teenage years, parents should keep an eye out for body image issues and unhealthy changes in eating habits like skipping breakfast, Paduch says.

“If they are a couple pounds overweight, it doesn’t take much (to upset them) if a peer says something,” Paduch says.

“It can have a lifelong impact on them if someone calls them fat, or they are being bullied (about their weight).”

If children start restricting their diet in unhealthy ways, their body may go into starvation mode or they may develop an eating disorder, Paduch says. Preteens and teens may need to be seen by a specialist or get therapy if they are being bullied.

“Sometimes how they cope can be destructive,” she says.

“They do need an outside person to help them. It’s very important to stay connected with your child.”

It’s tough, she says, but you can use food to help you here.

“Having those meals, sitting down and having conversations and time to allow kids to open up and express themselves is important,” she says.