Many mothers are told that by simply breastfeeding until their baby is ready for solids (around 4–6 months of age), and then introducing foods containing gluten (wheat, rye, or barley), they can help prevent celiac disease. In fact, baby gooroo reported on a previous study that concluded early introduction of small amounts of gluten-containing foods in breastfeeding children reduced (in a big way) the incidence of celiac disease. But two new studies show that for children with a family history of celiac disease, neither breastfeeding nor early introduction of gluten makes a difference in the development of the disease—though it may be possible to delay its onset, reducing negative effects on vital organs such as the brain.
Celiac disease is an autoimmune disorder in which eating gluten causes an immune response that attacks the small intestine. These attacks lead to damage in the lining of the intestine, making it difficult for the bowel to absorb nutrients properly. While celiac disease can be diagnosed at any age, common symptoms in infants and children include chronic diarrhea, vomiting, weight loss, irritability, and delayed growth. Left untreated, the disease can lead to serious health problems including Type I diabetes, multiple sclerosis (MS), osteoporosis, intestinal cancers, and infertility and miscarriage.
Celiac disease affects an estimated 1 percent of individuals worldwide. Genetics play a significant role in disease development; an estimated 1 in 22 individuals with a family history of the disease develop celiac and that risk increases to 1 in 10 if you have a first-degree relative (parent, sibling, child) with celiac disease. (It is worth noting that researchers are seeing an increase in the incidence of celiac, possibly due to better diagnostics.)
The only treatment for the disease is a strict gluten-free diet, which is why researchers have been looking for a key to preventing onset of the disease. Past research has suggested there may be a “window of opportunity,” an optimal time to introduce gluten to the digestive system that might protect against autoimmune response to it. According to this theory, introducing gluten too early (before 4 months) or too late (after 6 months) may increase the likelihood of developing celiac disease.
Contrary to past research, a pair of recent large-scale studies, published in the October issue of the New England Journal of Medicine, found that the only factor that significantly affected the diagnosis of celiac disease in early childhood was genetics.
Research
For the first study, researchers from the Working Group on Weaning and Celiac Disease Risk of the SIGENP (Italian Society of Pediatric Gastroenterology, Hepatology, and Nutrition) sought to determine whether delaying the introduction of gluten would reduce the risk of celiac disease in high-risk children.
They recruited 832 newborns from 20 medical centers in Italy between 2003 and 2008. All study participants had a first-degree relative (parent or sibling) with celiac disease. Infants were randomly assigned to either have gluten introduced in their diet at 6 months of age, or at 12 months of age. Children underwent genetic screening for genetic markers at 15 months of age, and additional screening at 24 and 36 months of age. A total of 707 children participated in the trial. The 154 children who were found, at 36 months of age, not to have genetic markers for celiac disease were excluded from further analysis, leaving 553 infants in the final study group. Of these children, 297 were in the group receiving dietary gluten for the first time at 6 months of age, while 256 were in the group receiving it at 12 months of age.
Researchers conducted interviews with parents to obtain information on diet and intestinal infections during the first year of life. Caregivers provided information about breastfeeding duration, but gave no details about frequency and exclusivity (only breastfeeding, only formula feeding, or combined feeding). Daily intake of cereal containing gluten was assessed with a 24-hour dietary recall questionnaire.
The participants underwent serologic screenings (blood tests that identify autoimmune diseases) for celiac disease at 15, 24 and 36 months. Testing was also conducted at 5, 8 and 10 years of age; however, while all study participants were age 5 when the study ended, not all were age 8 or 10. While 451 children had serological testing at age 5, only 89 were tested at age 10.
At any point when blood test results indicated celiac disease, a small-bowel biopsy was recommended for those children in order to confirm diagnosis. Biopsies were recommended for 117 children, and parents gave permission for biopsies in 112 children. Of those, 86 were confirmed with celiac diseases, and 26 were found to have potential celiac disease. Those children with confirmed celiac disease began a gluten-free diet. If celiac disease was not confirmed and if the child was symptom-free, a normal diet was continued.
The second study, conducted by a multidisciplinary European team, recruited 944 children ages 0 to 3 years through celiac disease organizations in eight European countries to determine whether daily ingestion of gluten during the so-called “window of opportunity” (4 through 6 months of age, when first exposure might prime the immune system to accept gluten) would reduce development of celiac disease in children. All study participants had positive serological testing for celiac disease genetic markers and a first-degree relative with the condition.
None of the children had gluten in their diets before 4 months of age. About half of the children were assigned to receive 200 milligrams of vital wheat gluten mixed with 1.8 grams of lactose daily from 16 to 24 weeks of age. The other half received a placebo, 2 grams of lactose. The study was randomized and double-blind. Neither the researchers nor the parents knew which substance each child received.
Researchers collected data on health history and diet. As in the first study, breastfeeding duration but not exclusivity or frequency was considered. In addition, the children underwent blood tests for celiac disease at least seven times during the first three years of life, and annually thereafter. Children who had elevated celiac disease-associated antibodies or who had symptoms consistent with celiac disease were offered small bowel biopsies. Celiac disease was confirmed in 77 children through biopsy by the age of 3. Three additional children were diagnosed with celiac disease without small bowel biopsies, due to their medical history.
Results
In the first study, researchers found that, for children with a family history of the disease, delaying introduction of gluten to 12 months did not reduce the risk of celiac disease development in the long-term. By age 5, there was no significant difference in celiac disease incidence between the groups of children who had gluten at 6 months and those who had it at 12 months. However, they did find that delaying the introduction of gluten until 12 months significantly reduced the risk of celiac disease among younger children. At age 2, there were significantly more children diagnosed with celiac disease in the group that received gluten at 6 months than in the group that waited until 12 months.
In other words, later introduction to gluten was associated with a delayed onset of disease. The median age of diagnosis of overt celiac disease was 26 months in the first group (those introduced to gluten at 6 months) and 34 months in the second group (those introduced to gluten at 12 months). Researchers acknowledge that this “might reduce the negative effect of the disease on vulnerable organs such as the brain” and reduce the prevalence “of celiac disease, at any age, among children carrying the high-risk genotype.”
The only factor that was significantly associated with developing celiac disease was the high-risk genetic marker, known as a human leukocyte antigen (HLA). The other variables (type of relative with celiac disease, number of affected relatives, dietary pattern, and early intestinal infections) showed no association with disease risk.
“Th[e first] study minimizes the role of infant nutrition and confirms the importance of genetic factors on diseases development,” says Dr. Carlo Catassi, president of the Italian Society for Pediatric Gastroenterology, Hepatology and Nutrition and an author of the first study.
The study researchers note that their data show no protective benefit of breastfeeding on the development of celiac disease, though past observational studies have shown such an effect. However, mean breastfeeding duration was similar in both groups (about six months)—far short of the American Academy of Pediatrics and World Health Organization goals. Also, while information about the duration of breastfeeding was collected, details about frequency and duration are not shared. The researchers note that the study was not designed to address this issue.
“We were surprised to find that breastfeeding was not protective against celiac disease development, given the results of previous studies on this topic,” says Dr. Catassi. “It should be observed anyhow that previous data were retrospective and only took into account cases of diagnosed celiac disease, whereas our study evaluated the overall prevalence of disease.”
In the second study, children in the gluten group did not have a significantly lower risk of celiac disease by age 3, compared to those in the placebo group (5.9 percent versus 4.5 percent). Breastfeeding, regardless of whether it was exclusive or ongoing during gluten introduction, did not significantly influence the development of celiac disease or the effect of the gluten intervention. This study did not bear out the idea of a “window of opportunity” for establishing protection from celiac disease through carefully timed early exposure to gluten.
Recommendations
Celiac disease is a serious autoimmune condition, and one for which more research is needed. These studies suggest that dietary changes in infancy may not reduce one’s risk of developing the disease, which may be primarily determined by genetic factors. However, infant feeding practices may help to delay onset in children at high risk for the disease. (Given the upward trend of celiac disease incidence, and the potential for development of celiac disease throughout the course of the lifetime, some researchers continue to investigate environmental factors.)
There are steps you can take to support your child’s health:
If your child is at high risk for celiac disease, consider delaying introduction of gluten to 12 months. The silver lining of the “6 or 12 months” study was that while similar numbers of children in each group ultimately were diagnosed with celiac disease, significantly fewer of those who waited until 12 months for gluten were found to have the disease at age 2. Given the brain development occurring in toddlerhood, any delay in celiac disease onset can be beneficial to your child’s overall health. “In general, age at gluten introduction doesn’t influence the risk of disease development, but may be partially protective for infants at high genetic risk,” Dr. Catassi explains. The delay in disease development could have a favorable impact on the development of sensitive organs such the central nervous system.
Follow nutritional guidelines. Although the “window of opportunity” for gluten exposure was thought to be from 4 months of age through 6 months of age, the “window of opportunity” study does not bear this out. It seems there is no benefit to early introduction (and given the findings of the first study, it may be better to wait). There is no need to rush your child and introduce gluten at this time; wait to start solid foods until 6 months of age, when your child shows signs of developmental readiness.
Breastfeed your child. Breastfeeding remains good for baby’s health for many other reasons, all of which will benefit children—even those who have been diagnosed with celiac disease.
Consider celiac disease screening for school-age children. While celiac disease can develop at any age, researchers in the “6 or 12 months” study concluded that 80 percent of the children in their study population who developed celiac disease did so within the first three years. “We therefore suggest that efficient screening for celiac disease may be carried out by testing school-age children,” the researchers state.
Talk with your child’s doctor. Discuss any family history of autoimmune disease, so you can make the best possible decisions and ensure proper nutrition for your child.
Alison DeNisco is a Connecticut-based writer with a master’s degree in magazine journalism from Columbia University Graduate School of Journalism. She is currently the editor of District Administration magazine, a national publication for K-12 school leaders. Her work has appeared in Psychology Today, Marie Claire, and the Huffington Post, as well as various newspapers nationwide. She spends her spare time reading, cooking, and going to concerts.
With additional reporting by Heidi Hauser Green
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