Is there a link between IBS and Food Allergy? In a study published in Nature titled “Local Immune response to food antigens drives meal-induced abdominal pain”, the authors explored the link.
IBS(Irritable bowel syndrome) is very common and a difficult to treat condition associated with GI symptoms following a meal. The relationship between these food related symptoms is unclear.
Previous studies have shown that local gastrointestinal immune reactions to food antigens is induced by bacterial infections in mice.
In mice studies, bacterial infections and toxins induced the production of food antigen-specific IgE antibodies. The immune response was limited to the intestines and there was no evidence of systemic response. Subsequent ingestions of the implied food allergen led to an IgE and mast cell dependent hypersensitive response. With abnormal pain signaling in the nervous system in the gut mediated by histamine.
Further studies explored the possibility of similar reactions in humans, with and without IBS, none of them had documented food allergies. Injections of common food allergens (gluten, wheat, soy and milk) in the gut led to local swelling and mast cell activation in each of the 12 IBS patients. And in the healthy volunteers without IBS, just 2 of 8 had isolated local reactions.
These finding suggest that a possible peripheral mechanism of food induced abdominal pain, associated with immune response to food allergens locally in the intestine.
This study opens the way for further studies of possible IBS treatments related to abdominal pain and mechanisms of mast cell activation and sensitization.
There seems to be a local mucosal IgE-mediated allergic response in the gut and absence of systemic sensitization. This study shows evidence of “local food allergy” in a mouse model of post infectious IBS patients, finding evidence of allergic reactions in the gut.
These preliminary studies support a link of IBS and food allergy. More studies will be needed to further support this link and if there is a strong link, how to identify which food allergens can exacerbate IBS.