Can you develop a food allergy later in life?

Hi Jessica,

Generally, people with allergies come from families in which allergies are common -- not necessarily to food but perhaps allergies to pollen, fur, feathers, or drugs. Thus, a person with two allergic parents is more likely to develop food allergies than someone with one allergic parent. It is possible to develop food allergies at a later time in life. 

Food allergy is a hypersensitivity reaction, meaning that before an allergic reaction to an allergen in food can occur, a person needs to have been exposed previously, or "sensitized," to the food. At the initial exposure, the allergen stimulates lymphocytes to produce the IgE antibody that is specific for the allergen. This IgE then is released and attaches to the surface of the mast cells in different tissues of the body. The next time the person eats that particular food, its allergen hones in on the specific IgE antibody on the surface of the mast cells and prompts the cells to release chemicals such as histamine. Depending upon the tissue in which they are released, these chemicals cause the various symptoms of food allergy. 

In adults, the most common foods that cause allergic reactions are shellfish, such as shrimp, crayfish, lobster, and crab; nuts from trees, such as walnuts; fish; eggs; and peanuts. Hope this information on food allergies has helped.

Best, 

Daisy