Allergic reactions to foods occur when the immune system identifies a food protein as a harmful substance and attacks it.
Some reactions are immediate, while others can be delayed by hours or even a few days. Symptoms can vary and frequently will increase in severity with continued exposure.
People just beginning to understand food allergies often find themselves overwhelmed with questions, especially when their children's health is at stake.
The following are some of the most commonly asked questions, along with answers whose accuracy was reviewed by local allergy specialist Dr. Seth Craig:
What are the symptoms or signs of allergies in infants?
Colic, difficulty sleeping, bloating or constant abdominal pain, frequent gas, blood or mucus in the stool, reflux or projectile vomiting, persistent infant acne, eczema, hives and slow growth.
Can an allergy be avoided?
There is no definitive way to avoid allergies. But doctors recommend that, if there is a family history of allergies, the mother avoid common allergens during the last trimester of pregnancy and while nursing.
Doctors also recommend that, when possible, mothers delay the introduction of solid foods and breast-feed exclusively for six months. Breast-feeding not only limits direct exposure to allergens, it also boosts the baby's immune system and allows the digestive system to mature.
How accurate are allergy tests?
Allergy testing is accurate even in infancy, but at any age, a positive test does not always predict an adverse reaction to actually eating the food. Nor does a negative test guarantee against future reactions. However, tests can frequently offer some needed information and give parents a starting point.
The most common initial test is the SPT, in which a small amount of protein is "scratched" onto the baby's skin. The doctor measures reaction based on a histamine control. Another test is the RAST, in which blood is sent off to a lab. Results take approximately one to three weeks to return.
If the tests are not completely accurate, how can I identify possible allergens?
An elimination diet for both the nursing mother and infant (if the baby is eating solids) can help narrow down problematic foods. The most effective diets are limited to three to five lower-allergenic, unprocessed foods, such as rice, lamb, olive oil, quinoa, sweet potatoes and beans. Add one new food every two weeks. If there is a reaction, remove the problematic food and wait another two weeks before adding another food.
Isn't there a shot?
There is no vaccine or shot to treat food allergies. There is no cure or treatment beyond avoidance. People with severe allergies carry EpiPens (shots containing epinephrine) in case of an anaphylactic reaction.
Who should be involved in my child's care?
It's very important that parents put together a strong, knowledgeable medical team. The team might include a pediatric allergist, a pediatric gastroenterologist, a nutritionist, a lactation consultant and a pediatrician.
Food allergies often appear as subtle behavioral changes or skin irritations that medical professionals can easily dismiss as normal. As parents, we know our babies, and we frequently have to trust our instincts and seek out a professional who will listen to our concerns--and refer us to a specialist when their own knowledge is limited.
What are the biggest challenges facing the parents of food-allergic children?
The first is school. Beyond the obvious lunchroom concerns, teachers have become accustomed to, using food in the classroom as a teaching tool.
Playgrounds, grocery stores and play groups also present hazards. Proteins from a small smear of peanut butter can still be dangerous six months later. Crumbs left in a grocery store cart can be the source of a sudden "mystery" reaction. (Parents learn to travel with antibacterial wipes to clean potentially hazardous surfaces.)
Inaccurate or unclear food labels also are problematic. Terms like dextrose and citric acid don't scream "corn," but that's just what they are. Supposedly lactose-free creamers frequently contain casein, a dairy protein. And the wax used on fresh produce can contain corn, soy or dairy.
Finding a variety of foods that are safe to eat and affordable can be tough--and frequently, those foods present baking challenges.
Prescription drugs can also be dicey. Medication is seldom well-labeled. Allergens lurk in sorbitol and glucose and natural flavoring. Many parents of food-allergic children build a strong relationship with a good compounding pharmacist.
The social scene can also be challenging. Even if a restaurant or friend is able to cook safe food, there's always concern about cross-contamination. (A pan or utensil used to cook "safe" foods can pass along allergens if it previously came in contact with other foods.) These concerns can be very isolating.
Brief, well-meaning contact with people can be harmful. People love to touch babies, but sometimes those touches are not just unhealthy, but potentially lethal.
Doctors, too, can create problems if they don't understand food allergies and make recommendations based on common myths.
Even among family and friends, it's hard to find people who really understand or accept the full impact of food allergies, and who are willing to adjust their lifestyle or environment even temporarily to remove potentially deadly allergens.