A recent Finnish study investigated whether there is a link between infant formulas based on cow’s milk and celiac disease.
Celiac disease is a serious autoimmune disease triggered by foods containing gluten. Gluten, a protein found in many grains, activates an immune response in the small intestine that causes chronic inflammation. If the inflammation is left unchecked, it becomes chronic and eventually damages the small intestine. The small intestine can be damaged to the point when it is unable to absorb nutrients efficiently.
Studies have shown that the risk of developing celiac disease is not linked to the age when infants first consume gluten. Rather there may be a genetic basis. Many individuals with celiac disease carry the HLA DQ2 and/or HLA DQ8 genes. These two genes are associated with an increased risk of developing type 1 diabetes.
Avoiding formula based on cow’s milk reduced antibodies associated with diabetes
Individuals with type 1 diabetes and those with celiac disease often have high levels of antibodies against the proteins found in cow’s milk. The body can also develop antibodies against its own proteins called autoantibodies, which are the typical cause of many autoimmune diseases. When infants with type 1 diabetes (who also carry the HLA DQ2 and/or DQ8 genes) avoided cow’s milk-based formula, the overall levels of diabetes-associated autoantibodies substantially decreased by the time the children were ten years old. A team in Finland wanted to know if the same was true for celiac disease.
Will the same results occur in infants with celiac disease?
The researchers wanted to determine whether a baby formula, one in which the cow’s milk proteins are broken down into small segments, could decrease the risk of celiac disease autoimmunity in children carrying the HLA DQ2 and/or HLA DQ8 genes. They also looked at whether high levels of cow’s milk antibodies could predict celiac disease autoimmunity or celiac disease. The team followed 230 Finnish infants for ten years and published their findings in Gastroenterology.
The researchers randomly divided the infants into two groups. These infants were all likely to have HLA-based type 1 diabetes and had at least one family member with this disease. Infants were fed either a conventional cow’s milk formula or a formula in which the cow’s milk proteins were broken down into small segments. These formulas were intended to supplement breastfeeding until the infants were six to eight months old. The team collected a series of serum samples from the children. They used the samples taken for the first 24 months to test for antibodies to cow’s milk, and they used the samples taken until the children were ten years old to detect celiac disease autoantibodies (TG2A).
No differences found between different formula groups
Although 25 children tested positive for celiac disease autoantibodies, only eight of these children eventually developed celiac disease. These children were equally divided between the two groups indicating that the test formula presented no protective or preventative effects.
The eight children who developed celiac disease also had significantly higher levels of antibodies for proteins found in cow’s milk compared to the other children, even those with celiac disease autoantibodies. These antibodies were detected as early as three months of age. As this occurred before the infants first began eating gluten-containing cereals, this result suggests that changes to gut permeability have already occurred before exposure to gluten and the development of celiac disease.
Mechanisms underlying celiac disease are complicated
Although there is a possibility that these results may not apply to the general population, the results demonstrate that the mechanisms underlying celiac disease are more complicated and occur much earlier than we thought. Future research needs to focus on the interplay of genetic and environmental factors, on increased levels of antibodies for dietary proteins, such as those found in cow’s milk, and how these factors all relate to increased gut permeability.
Written by Natasha Tetlow, PhD
Reference: Hyytinen M, et al. Avoidance of cow’s milk-based formula for at-risk infants does not reduce development of celiac disease: a randomized controlled trial. Gastroenterology. 2017; 153:961-970.