When a person eats food he is allergic to, his immune system triggers any number of allergic responses. Gastrointestinal symptoms occur when the GI tract becomes inflamed, resulting in stomach pain and other digestive problems like vomiting, diarrhea, constipation or blood in the stool, according to an October 2005 issue of the journal "Nutrition in Clinical Practice." The person may also experience other symptoms such as hives and swelling, eczema, wheezing or difficulty breathing.
Milk Allergy
A milk allergy is common in children, affecting about 2.5 percent of infants and toddlers, notes a publication from the American Academy of Allergy Asthma & Immunology. Cow's milk formula-fed infants and toddlers ingesting cow's milk are the most commonly affected group. However, a breastfed baby may also experience allergic reaction through the mother's milk. Sources of foods that cause milk allergy include all milk and dairy products from sheep, goat or cow.
Egg Allergy
Egg allergies affect around 2.5 percent of children, causing digestive problems such as stomach cramps, vomiting and diarrhea; asthma; rhinitis; and hives within minutes of eating egg. This allergy can also cause anaphylaxis, a life-threatening response that includes swollen throat, shock, stomach pain and cramping, rapid pulse and dizziness, notes MayoClinic.com. Egg allergy is difficult to avoid because egg is a basic ingredient in many baked good, processed meats, deserts and noodles.
Peanuts and Nuts
According to MayoClinic.com, even tiny amounts of peanuts and nuts can elicit an allergic reaction that ranges from mild to life-threatening, within minutes to hours of exposure. Persons allergic to peanuts and nuts can experience gastrointestinal symptoms that include stomach cramps, diarrhea, nausea or vomiting. Digestive problems can happen when a person eats peanuts or peanut-containing foods, cross-contaminated foods processed in the same facility as peanuts or nuts.
Shellfish Allergy
Although shellfish allergy is more common in adults, children with shellfish allergy rarely outgrow them, notes the AAAAI. Even tiny amounts of ingested shellfish can cause allergic gastrointestinal reactions such as pain, diarrhea, nausea or vomiting, notes MayoClinic.com. Further, allergic response to shellfish can be potentially severe as even small amounts may bring about a reaction and usually result in anaphylaxis, notes the AAAAI. People who are allergic to one kind of shellfish may also react to other kinds.
References
- "Nutrition in Clinical Practice"; Gastrointestinal manifestations of food allergies in pediatric patients; M. Garcia-Careaga; October 2005.
- American Academy of Allergy Asthma & Immunology: Food Allergy Practice Parameter
- MayoClinic.com: Egg Allergy
- MayoClinic.com: Peanut Allergy
- MayoClinic.com: Shellfish Allergy
