NEW YORK – Children with autism tend to be picky eaters, but a new study suggests that their growth may not be impaired because of it.
The study, which followed 79 UK children with autism spectrum disorders (ASDs) and nearly 13,000 autism-free children to the age of 7, found that although children with ASDs were more often rated as picky eaters by their parents, their average intake of calories and major nutrients was similar to their peers'.
Moreover, there were no differences in the two groups' weight and height attainment, researchers report in the journal Pediatrics.
"We think that these are reassuring findings, and that in general, parents of children with ASD symptoms need not worry that their children will not grow properly," Dr. Pauline Emmett, a senior research fellow at the University of Bristol in the UK, told Reuters Health in an email.
But, she noted, parents who are worried about their child's eating habits should bring it up with their doctor — and can ask for a referral to a dietitian if they want more advice.
The term "autism spectrum disorders" refers to a group of developmental disorders that hinder people's ability to communicate and build relationships. The conditions range from severe cases of "classical" autism to Asperger's syndrome — a disorder in which a person has normal intelligence and verbal skills, but difficulty socializing and understanding subtler forms of communication, like body language and vocal tone.
It's been known that children with ASDs often have unusual eating patterns or will only eat a limited selection of foods — at least in part because of the general aversion to new experiences and the repetitive, ritualistic behaviors that mark the disorders.
But whether that tendency toward picky eating has consequences as far as growth and development has been unclear.
For the new study, Emmett and her colleagues used data from a long-term project that has followed the health of nearly 14,000 UK children since their birth in 1991 to 1992.
Of those children, 79 were diagnosed with an ASD at some point, including 30 with classical autism and 23 with Asperger's. The rest were diagnosed with "atypical" autism, which shares some of the features of classical autism but tends to be milder, or could not have their ASD classified.
Overall, children with ASDs had less varied diets than their peers, based on parents' responses to dietary questionnaires completed when their children were 6 months, 15 months and 2, 3 and 4 years old.
At the age of 4, for example, 37 percent of children with ASDs were deemed to be "very choosy" eaters, versus 14 percent of children without the disorders. Among those with ASDs, children with classical autism had more-limited diets than those with other ASD types.
However, the average intakes of calories, protein, fat and carbohydrates were all similar between children with ASDs and those without. And while children with the disorders tended to eat fewer vegetables and fruit than other children, they also drank less soda and ate fewer sweets.
There were also no differences between the two groups of children when it came to average height, weight and body mass index — a measure of weight in relation to height — or in blood levels of iron.
There were two differences in the children's diets overall: those with ASDs averaged less vitamin C — probably, the researchers note, because they ate fewer fruits and vegetables — and less vitamin D, which is obtained in the diet mainly from fortified milk products and fish.
Those vitamin gaps were not large, however, and were "unlikely to be important for the majority of the children," Emmett said.
Still, she added, the study looked at average differences between two groups of children. It's possible that some individual children with ASDs had deficiencies in vitamins C or D.
The bottom line for parents, the researchers say, is that, despite their often-picky eating, children with ASDs seem to typically get enough major nutrients and grow normally.
They do point out, however, that if children with ASDs have "extreme" limits on what they will eat, it may signal an eating disorder that needs attention.