July 19, 2010 -- Children with autism spectrum disorder tend to be extremely picky when it comes to what they will or won't eat, but new research shows that it doesn't seem to affect their growth and development.
The findings appear in the August issue of Pediatrics.
"Although the autism spectrum disorder [ASD] children were eating less variety of foods compared to the rest, they were not growing less well or more likely to have anemia (low levels of iron in the blood)," says Pauline Emmett, PhD, a senior research fellow at the Nutrition Centre for Child & Adolescent Health at the University of Bristol, England, in an email. "Their diets were similar in energy and most nutrients, so it suggests that parents of ASD children can relax a little about whether the diet their children are eating is likely to be adequate."
The CDC estimates that about one in 110 children in the U.S. have an autism spectrum disorder, the umbrella term given to a group of disorders that can range from the mild to the severe and that often affect social interaction and communication.
Feeding Problems Show Up Early in Autism
In the new study, children who were on the autism spectrum started eating solid foods later than their counterparts who did not have autism, and they were more likely to be called "slow-feeders" by their moms starting at around 6 months of age.
Children with autism were also described as "difficult to feed" and "very choosy" from the age of 15 months to 4.5 years, when compared with children not affected by autism, the study shows. Starting at age 15 months, children with autism tended to eat a more selective diet than their counterparts without ASD and were less likely to eat the same foods as their moms starting at age 2. By 4.5 years, 8% of children with autism in the study were on a special diet.
No Effect on Nutritional Status
In general, children with an autism spectrum disorder ate fewer vegetables and fruit, sweets, and carbonated drinks than their counterparts without autism. Still, these eating habits did not have any bearing on energy or calorie intake or result in any significant nutritional shortfalls at age 7.
"There are many ways of making up an adequate diet, and although nutritionists usually advise 'plenty of variety' in foods eaten, a less varied diet can be adequate," Emmett says.
"If the behaviors are very extreme in a minority of ASD children there could be a chance of nutritional inadequacy, but our study is saying that this is not the case for the majority," she says. "Parents who are worried about this should see their family doctor or ask to see a trained registered dietitian."
Daniel Coury, MD, chief of developmental behavioral pediatrics at Nationwide Children's Hospital in Columbus, Ohio, and the medical director of the Autism Treatment Network, says that the findings are reassuring for many parents. "If parents are concerned about nutritional intake among their children with autism because they eat a selective diet, it looks like most are getting adequate nutrition," he says.
The Autism Treatment Network is a network of 14 centers across the U.S. and Canada focused on developing standards of care for treating children with autism spectrum disorder.
"There has been concern that food preferences reflect parents' food preferences [meaning] if mama doesn't liked broccoli, she won't serve broccoli, and this study suggests that intrinsic food selectivity in children on the spectrum is probably related to the spectrum, not their parents' eating habits," he says.
This too should help vindicate parents who may blame themselves for their children's food or feeding issues, Coury says.
Picky Eating Is Not a Red Flag
None of this should suggest that finicky eating is a sign of autism, he stresses.
"If you have a picky eater or a child that is difficult to feed, this does not mean that they have autism or even are at increased risk," Coury tells WebMD. "The children in this study were more likely to have feeding issues, but if a parent of a 4-month-old or an 8-month-old is trying to get their toddler to eat baby food and their baby is refusing, I would not worry."
Autism is more of a big-picture diagnosis, he says.
"At this young age, hallmarks of autism are in the social and communication areas, so if the child is socially showing interest and interaction with parents and siblings, that is a good sign," Coury says. "If the child is starting to mimic sounds and use words and repeat words like mama and dada, these are also good signs."
The new findings may not apply to the autism diet, a gluten-free, casein-free eating plan that has grown in popularity in the U.S.
"It depends on the special diet, but nutritional deficiencies are a possibility depending on what they are focused on, and some diets may require supplementing," he says. "If your child is not on a regular diet, you may need some monitoring to make sure that all their nutritional needs are being met."
Coury's advice? Run it by your doctor.
Susan Hyman MD, an associate professor of pediatrics and the division chief of neurodevelopmental and behavioral pediatrics at Golisano Children's Hospital of the University of Rochester Medical Center, N.Y., agrees. "When you manipulate what children would normally eat, you change the rules," she says. "This study would not be reassuring if your child eats a little mac and cheese, a little frozen waffle and 30 or so other foods, which is a more typical restricted autism diet," she says.
That said, "this is a lovely study and what it does is give increased awareness on the part of parents and pediatricians that feeding problems may just be feeding problems, but need to be interpreted as they may be another set of behaviors to alert you that something may be different," Hyman says.
"This is helpful information as we whittle away at the behaviors associated with autism and the health problems that are secondary to autism," she tells WebMD.