Many symptoms of RAP are common to the symptoms of allergies/intolerances that are often triggered in relation to meals (during or after meals).
Hence the idea that certain foods are the underlying cause of the pain.
The most common suspect foods are gluten and milk.
However, there is no evidence in the scientific literature demonstrating that a gluten-free or dairy-free diet has any benefit in patients with RAP, once coeliac disease, non-coeliac gluten sensitivity, wheat allergy and primary lactose intolerance have been ruled out.
Some patients exclude gluten from their diet on their own initiative and experience an improvement. This may be simply because gluten contains fructans, which are sugars that are fermented in the gut producing wind and bloating. They feel better because they reduce the fructans in the diet, not because they exclude the gluten. Coeliac disease, non-coeliac intolerance and gluten allergy should be ruled out before switching to a gluten-free diet.
There are also patients who experience a clear cause-and-effect relationship when they eat some foods in particular, for example legumes. If the relationship is clear, it is advisable to avoid the food in question.
With regard to the food intolerance tests that may be found in pharmacies, it is important to note that their use is not endorsed by any medical or scientific society. They are based on the detection of IgG or IgA antibodies against multiple food proteins, but they are antibodies that have no role in the origin or development of allergies or intolerances. They are expensive and their results are not reproducible, that is, if we were to repeat them in the same person, they would probably give a different result. Moreover, following an exclusion diet based on the results of the test can lead to nutritional restrictions with negative consequences on health, particularly in children, who are in full growth and development