(CNN)Frustrated with your child's picky eating? If you're trying to fix the problem by becoming the food police, you're probably making your child's habit of picky eating worse, according to a new study that followed more than 300 parent-and-child pairs for five years.
Demanding that a child eat, or restricting food are associated with some of the pickiest eaters, according to the study, published Tuesday in the journal Pediatrics.
"Eating is one of the few domains kids can exert some control over," said senior author Dr. Megan Pesch, a developmental and behavioral pediatrician at Michigan Medicine C.S. Mott Children's Hospital.
Lower levels of picky eating in children were associated with parents imposing few restrictions on foods and a lack of pressure to eat.
Families in the study were eligible for the United States Department of Health and Human Services' Head Start program, meaning they were living at or below the federal government's poverty level for a family of four, currently $25,000 a year. Researchers asked parents to respond to questionnaires describing their child's level of picky eating and how the parents were handling the issue.
Parent completed the questionnaires when their child was 4, 5, 8 and 9 years old.
"What makes this study really unique is that we were able to map this behavior over a longer period of time," Pesch said, adding that the study did not find that a child grew out of his or her picky eating behavior within that five years. Whether that would continue as the child grew, she said, was an "important question for future study."
Children were divided into levels of low, medium and high pickiness about food. About 15% of the children in the study fell into the "high" picky eater group, in which children didn't accept vegetables often or were highly nervous about new foods.
These kids probably have "thousands of negative memories about food," such as conflict over meals, unexpected tastes and discomfort, said Nancy Zucker, a Duke University School of Medicine associate professor of psychiatry, and Sheryl Hughes, Baylor College of Medicine associate professor of pediatric nutrition, in an accompanying editorial.
"It is critical that caregivers let go of their need for a child to taste something and instead focus on accumulating pleasant experiences," they wrote.
"Don't force kids to clean their plate," Pesch said. "Don't make them sit at the dinner table until they eat a certain amount of the food. And avoid bribing with food."
That can be hard for parents, Pesch acknowledged, sharing that she too struggles not to do the same with her three small children.
"It's a natural inclination to say, 'If you eat your green beans, you can have dessert.' But that can backfire and create an even larger negative association with that food," she said.
The study found no difference among children due to socioeconomic demographics, but did find higher rates of picky eating among children who had problems regulating their emotions. Those children were more prone to exaggerated changes in mood with possible heightened irritability or temper.
"Some kids are wired to be more cautious, to be a little bit more anxious," Pesch said. "I don't think parents should really feel a personal blame for this. Some kids are just going to be picky."
Try these 'best practices'
Because picky eating was evident by age 4 and didn't ease during the five years of the study, "interventions need to begin at younger ages because of the stability of picky eating trajectories over time," wrote Zucker and Hughes in the editorial.
The best time to introduce new foods is when the baby begins solid foods at six months, experts said, and then continue to offer a variety of foods throughout the formative years of toddlerhood.
Pediatrician Dr. Tanya Altmann, author of "What to Feed Your Baby" has a list of "11 foundation foods" she believes will help children learn to love healthy food. "Let your infant lean in and open his mouth when he wants to eat," Altmann told CNN in a prior interview. "Don't force feed or play airplane games -- that doesn't help."
More tips from experts, which can apply at almost any age, include:
Don't give up on a food. One of the best practices for parents dealing with picky eaters is to expose your child to the food multiple times, experts said, and always without stress.
"It might take multiple times before they even tolerate having it on their plate or are interested in taking a bite. But keep putting it on the dinner table," Pesch suggested.
If fact nutrition science research suggested kids may need up to 12 exposures — not eating, just exposures such as looking at it or helping prepare it — to say they "like" a food. Interrupt that with a negative experience, and they may prematurely put the food into the "don't like" bucket.
Role model enjoying the food. Parents and older siblings and caregivers should role model eating and enjoying a variety of foods, experts said.
"Seeing someone who is loved and trusted eating that food multiple times will normalize it a bit and that has been shown to increase food acceptance, especially for those children who may have a more anxious or cautious temperament," Pesch said.
Involve kids in picking out food and preparing it. When you go to the grocery store, have your child choose one or two vegetables, and, if possible, let her help prepare the food to eat.
"Seeing where the food comes from and getting them to participate in the preparation demystifies it a little bit," Pesch said. "They can become more connected with the food and proud of something they did, which creates more positive associations with the intake of novel food."
Give options. Don't give in to the "green beans is the only vegetable my child will eat," experts said. That just teaches your child that meal time is monotonous. Variety is the spice of life, so to speak.
Make meals fun. Sit down as a family for meals, without TV or phones. Then tell stories, ask everyone about their day, play fun music — the choices are endless for making mealtimes something to look forward to. That also reinforces that food is for fuel, not fighting, and puts mealtime into the category of a pleasurable activity that builds family togetherness.
Don't make separate meals. If your child has developed some picky notions about what she will eat, don't fall into the trap of making a meal for her and a meal for the rest of the family. Have something nutritious she can eat on the table, and then let it be, experts said.
Picky eaters and weight
The good news about picky eating is that studies show it doesn't appear to cause weight gain. That was evident in this new study as well, where picky eating was associated with lower body mass (BMI) scores. Is that because of their poor nutrition?
"Picky eaters do generally tend to eat high-carb, high-fat, hyper-palatable processed foods more," Pesch said. "Yet studies have really shown that in developed countries, like the United States, we don't see many — if any — micro-nutrient deficiencies in picky eaters.
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"I go back to the mac-and-cheese dinner sort of picky eater — even if it's not the healthiest food choice, it's been enriched with some vitamins and minerals and so at least the picky eaters aren't lacking," Pesch added. "So overall we're seeing that these kids are growing well, which I hope can be really reassuring for parents."
More reassuring: Giving up the power struggle over food may actually cut your child's picky eating behavior. If it doesn't, experts say there's no shame in reaching out to your pediatrician or nutrition health professional for more advice.
