"If your baby is allergic to a food, her body treats the food like an invader and launches an immune-system attack," says BabyCenter.com, an informational website for parents of infants. Food allergies in babies and young children occur more often than what was once thought; they affect about 1 in 18 kids under 3 years old, according to pediatrician Dr. Alan Greene, creator of DrGreene.com. He also says they're most likely to occur in a baby with a family history of allergies, asthma or eczema.
Gastrointestinal Symptoms
If a baby has food allergies and is being breastfed, she can react adversely to what the mother eats. 90% of food allergies in babies result from cow's milk, soy, eggs, peanuts or wheat, according to Dr. Greene. Colic is a typical symptom of allergies, he says, both with breastfed and formula-fed infants who are allergic to an ingredient in the formula. Of course, babies eating solid foods can have allergies, too. Other gastrointestinal symptoms include excess gas, diarrhea, constipation, vomiting and nausea. Allergies to cow's milk sometimes cause mucus or streaks of blood in a baby's stools, which can sometimes cause anemia.
Respiratory Symptoms
It may seem more likely to result from an allergy to pollen or dust, but foods allergies can bring on stuffy or runny noses, and red, watery eyes in a baby. They can also trigger breathing problems like wheezing or asthma attacks.
External Symptoms
Typical reactions to food allergies don't just happen inside the body; a baby can get immediate or long-term symptoms that often prove quite visible. Hives can also occur within minutes of eating a food a baby's allergic to, while eczema--marked by scaly dry patches of skin on the arms, legs or face--can become an ongoing issue, says BabyCenter.com. They caution that a baby can react to a food even if he's previously eaten it without any problem, especially if the allergy tendency is inherited. In some babies, food allergies become severe, and even just touching the food in question can result in tingling, itching or swelling of the tongue, lips and throat--or even anaphylactic shock, which can include the above symptoms as well as skin welts, lung spasms and a sudden blood pressure drop. The foods most likely to cause life-threatening allergic reactions include nuts, peanuts, fish and shellfish. If your baby experiences severe allergic reactions, call 911 right away.
