Too much white bread and pasta fed to at-risk kids under age 5 could increase their odds of developing celiac disease, a new international study has concluded.
Every extra daily gram of gluten a young child eats increases their risk of celiac disease, if they are genetically predisposed to it, researchers found.
For example, eating an extra half-slice of white bread every day at age 2 can increase a kid's risk of celiac disease at age 3 by 7%, according to findings published Aug. 13 in the Journal of the American Medical Association.
"The kids who went on to celiac disease were consuming more gluten in their diet in early childhood," said study co-author Jill Norris, head of epidemiology at the University of Colorado's School of Public Health.
However, Norris' team warned it's too soon to recommend eliminating gluten from the diets of young children, even those with a genetic risk for celiac disease.
"The worry is you would cut out healthy foods high in fiber and other nutrients simply to cut out gluten," Norris said. "There are ways to remove gluten from the diet and maintain a healthy diet, but it's actually quite difficult."
Who's at risk?
Celiac disease is an immune reaction in the small intestine to gluten, a protein found in some grains. It often causes diarrhea, fatigue, weight loss, bloating, abdominal pain and anemia, and can lead to serious complications.
A person with a parent, child or sibling who has celiac disease carries a 1-in-10 chance of developing the disorder, according to the Celiac Disease Foundation.
It often develops in early childhood, but it hasn't been clear why some kids at risk for celiac disease wind up with it while others don't, Norris said.
"Virtually everybody is exposed to gluten during their lifetime, and there are a number of people who we consider genetically at increased risk but they never get the disease," Norris said. "We're trying to figure out what's different about the people who do end up getting the disease."
For this study, researchers followed more than 6,600 children from birth through age 15 at six clinical research centers in Finland, Germany, Sweden and the United States. All had an inherited risk for celiac disease.
Their diets and gluten intake were tracked based on three-day food diaries taken at regular intervals throughout their lives.
About 18% of the kids developed autoimmune responses related to celiac disease and 7% developed full-blown celiac disease, with the onset of both conditions peaking at 2 to 3 years of age, researchers found.
Every 1-gram increase in daily gluten intake -- about a half-slice of white bread -- at age 2 was associated with an increased chance of celiac disease by age 3, they concluded.
"We can now confirm that besides certain genes, high intake of gluten also is an important risk factor for celiac disease," said senior researcher Dr. Daniel Agardh, a pediatrician with the Diabetes and Celiac Disease Unit at Lund University in Sweden.
Tough to 'micromanage' diet
Still, more research is needed before doctors can offer parents solid advice about their young child's diet, experts said.
Other possible factors in celiac disease still need to be considered, such as early childhood infections, changes in gut bacteria, and antibiotic exposure, noted Dr. Jacqueline Jossen. She's a pediatric gastroenterologist at the Susan and Leonard Feinstein Inflammatory Bowel Disease Clinical Center at Mount Sinai Hospital in New York City.
"There's a lot that was not specifically analyzed in this study, and there is previous literature to suggest those things may have a role as well," said Jossen, who had no part in the research.
At this point, she wouldn't recommend any dietary changes based off these findings.
"It's such a small amount of gluten they're talking about here. Even half a slice of bread can make a difference? Even on a practical level, it's hard to micromanage something like that," Jossen said.
Jossen speaks from experience. She has celiac disease and has a 3-year-old daughter with a genetic predisposition toward the condition.
"Even for me on a personal level, I wouldn't change her diet based on this yet," Jossen said of her daughter.
Is testing worth it?
And how do you even know for sure that you or your child is at risk?
Genetic tests for celiac disease risk are available, but often are not covered by insurance, said Dr. Maureen Leonard, clinical director of the Center for Celiac Research and Treatment at MassGeneral Hospital for Children in Boston.
"Online commercially available tests do not always assess all compatible genes for celiac disease," said Leonard, who wrote an editorial published with the study. "Therefore, I would suggest parents speak with their physician about whether a genetic test may be appropriate for their child."
Agardh doesn't think genetic testing would be of much help, "since these genes are common in the general population."
"In fact, the majority of individuals carrying these risk genes eating gluten will not develop celiac disease," he said.
A second study this week in JAMA Pediatrics found that gluten also can boost children's risk of developing type 1 diabetes.
Among children with a genetic susceptibility for type 1 diabetes, a high intake of gluten was associated with an increased risk of an immune response that can damage or destroy the body's ability to produce insulin over time.
"Given that these cereals are eaten by most children daily and are important sources of many essential nutrients, further studies are warranted to confirm or rule out the findings," said the authors led by Leena Hakola from Tampere University in Finland.
The Celiac Disease Foundation has more about celiac disease.