NEW YORK (Reuters Health) - For babies at higher risk of childhood diabetes because of family history or genes, a gluten-free diet in the first year of life does not lower the chances of developing the disease, German researchers report.
The findings undercut previous studies, including work from the same scientists, suggesting that babies exposed to gluten as part of their early diet might be more likely to develop type 1 diabetes later in childhood.
Although the new study included only 150 children, Dorothy Becker, director of the diabetes program at Children’s Hospital of Pittsburgh, told Reuters Health the results are reasonably clear.
“It doesn’t mean that it if you did a huge study there wouldn’t be an effect (of gluten),” said Becker, who was not involved in the study. “But it makes it unlikely.”
Gluten is the protein in wheat and other grains that makes dough elastic and gives bread its chewiness. Roughly 1 percent of people in the United States have a condition called celiac disease, in which immune reactions to gluten damage the intestines.
Each year about 20 kids per 100,000 under the age of 10 in the U.S. are diagnosed with type 1 diabetes, according to the National Institutes of Health. In contrast with type 2 diabetes, which is usually a disease of adults and associated with old age or obesity, type 1 diabetes typically strikes children.
Many of them likely inherited a genetic predisposition to the disease from their parents. Yet genes alone don’t fully explain why people develop the condition. Other factors, such as environmental exposures, are thought to be necessary to trigger it.
In the latest study, the researchers followed 150 babies with at least one parent or sibling who had been diagnosed with type 1 diabetes — marked by the death of islet cells in the pancreas that secrete the hormone insulin. The body requires insulin to convert dietary sugars into energy.
Half of the children were exposed to gluten in their diet for the first time at the age of six months. For the rest, exposure to the protein was delayed until after their first birthday.
The different diets appeared to have no impact on the babies’ ability to grow or gain weight.
By age 3, three children exposed to gluten early had developed type 1 diabetes, compared to four in the late-exposure group. Signs that the children had developed immune reactions to their own islet cells - a possible precursor to diabetes, especially in those with a genetic predisposition for the disorder - appeared in 11 children given gluten at six months of age, compared to 13 who first ate gluten when they were 12 months old.
Some research has suggested that delaying exposure to gluten can increase the risk of developing celiac disease. However, the German scientists said they found no evidence for such a link.
Roughly 30 percent of parents said they did not strictly follow the diet plan. Still, the researchers said, the results of the study show that although delaying the introduction of gluten into a baby’s diet causes no harm, it doesn’t appear to reduce the risk of diabetes or immune-related early-indicators of insulin problems.
The researchers did not respond to requests for comment on their study, which appeared online last month in the journal Diabetes Care.
Research into other potential food triggers for type 1 diabetes is ongoing. Last November, researchers in Finland reported that babies with a genetic predisposition for type 1 diabetes who were fed an infant formula called Nutramigen were about half as likely as those given conventional cows’ milk formulas to show signs of islet cell autoimmunity later in childhood. The milk proteins in Nutramigen (sold as Enfamil by Mead Johnson & Co.) are altered in a way that makes them more tolerable to the immune system.
Becker is helping to lead a large international trial funded by the National Institutes of Health to further explore the Finish findings. The results of that study, which includes nearly 2,200 babies, are expected in 2017, she said.
SOURCE: bit.ly/hzGutn Diabetes Care, online April 22, 2011.