Celiac disease is hereditary, according to the Celiac Disease Foundation. The illness sometimes runs in the family. A person whose parent, brother, or sister, for example, have celiac disease has a 1 in 10 risk of developing the condition as well.
About 90% of people with celiac disease have the HLA-DQ2 or the HLA-DQ8 gene, both of which help the immune system recognize foreign objects such as viruses and bacteria that need to be killed. About 30% of people carry those genes. Because having the gene only means you’re at risk of developing celiac disease, but won’t necessarily develop it — only about 5% of this group actually develop celiac disease.
Other autoimmune disorder
Celiac disease is an autoimmune disorder — disorders where the immune system attacks the body. When a person with celiac disease eats foods containing gluten — a protein found in wheat, rye, and barley — the immune system reacts by attacking the small intestine, hindering nutrient absorption. People with one autoimmune disorder are prone to developing other autoimmune disorders, and the risk increases with age, but why that is is unclear. Two of the more common autoimmune conditions in people with celiac disease are type 1 diabetes and rheumatoid arthritis.
Being overweight or obese
It’s common for celiac disease patients to be overweight, and as many as 13% may be obese, according to research cited by the Celiac Disease Foundation. The reason is the diet — gluten-free foods are often low in fiber, and many processed gluten-free foods have high glycemic index, more fat, and not much protein.
Diet during infancy
An emerging body of research is exploring the connection between feeding practices during infancy and developing celiac disease during adulthood. While the science is not conclusive, some research suggests a link between the duration of breastfeeding and a lower risk of celiac disease, at least the early onset disease. Other studies show no evidence that breast milk has any effect on the risk of celiac disease. However, the research still recommends breastfeeding.