Why do we develop Food Sensitivities? It is not exactly clear as to why individuals develop food sensitivities and allergies in the first place. The loss of oral tolerance can possibly develop due to stress, antibiotic use, NSAIDs, hormone imbalance, environmental toxins, and any disturbance to the microbiota. Even eating the same food repeatedly can be a contributor to a food sensitivity. Your gastrointestinal tract has a barrier that allows food to enter your body. But any disruption in this barrier can allow improperly digested foods to enter and cause an immune reaction; therefore, creating a food sensitivity. Although we may not know the exact cause, we can certainly find out which foods that we commonly eat are giving us an immune response and making us sick.