Explain, at a physiologic level, what causes the allergic responses Tyler experiences when he eats peanuts and other legumes. Specifically, how is this related to protein nutrition, digestion, and absorption?

Answer 1

A peanut allergy is an abnormal response of the body to the proteins found in peanuts. As explained in the chapter, sometimes larger proteins can be absorbed into the blood and circulate. In the case of a peanut allergy, the larger protein that is circulating in the blood would be known as an allergen, a type of protein that the body physiologically mounts an immune response against. The immune response to a large polypeptide (protein) is known as an “allergic response” (this is an oversensitive immune response) and commonly called a food allergy. In Tyler’s case, the specific food allergy is known as a peanut allergy. When the body recognizes the allergen (peanuts and legumes) it will release histamines that cause swelling, itching, mucus production, muscle spasms, hives, rashes, and a variety of other responses that are unique to each individual. This oversensitive immune response by Tyler is known as the inflammatory response and can be quite serious and possibly fatal. An epinephrine injection is necessary to slow this over-zealous inflammatory response.
The “allergen” is the protein(s) in the peanut products or legumes. So, Tyler’s diet must provide adequate protein (including all essential amino acids) without using any of the proteins harmful to his immune system.