The scenarios above are examples of patients with food allergies. Food allergies can be difficult to identify initially as they present with a wide range of symptoms and history of onset.
An allergic reaction to food is immune-mediated. Meaning the body’s immune system identifies the food as something foreign that should be attacked and expelled from the body. The symptoms observed therefore, are the result of the immune system at work (although inappropriately so). Many organs/area of the body can be affected, only a small amount of food is required to illicit a reaction, and symptoms can present immediately.
No. The difference between food intolerance and food allergy is that with food intolerance small amounts of the food can often be eaten without the individual suffering from symptoms. Moreover, the symptoms when experienced are limited to the digestive system (such as bloating, cramping, diarrhea, and vomiting). Examples of food intolerance include: food poisoning, lactose intolerance, or celiac disease where the offending agents are bacteria, lactose, and gluten respectively.
Food allergies are more common in children than in adults. Six to eight percent of children under the age of three and approximately four percent of adults have a food allergy. However, children who suffer from other immune-mediated conditions such as eczema or asthma are more likely to suffer from a food allergy. Foods that often trigger an allergic response include: cow’s milk, eggs, soybeans, wheat, seafood, and peanuts.
The signs and symptoms of food allergies vary greatly. Reactions can be mild effecting only one part of the body to severe effecting multiple areas/organs of the body. Shock and anaphylaxis are a result of severe food allergies.
Food allergies may affect the skin causing a raised itchy rash referred to as hives, tissue swelling surrounding the eyes and mouth, or wheezing sounds in the respiratory tract. Food allergies may also affect the gastrointestinal tract causing vomiting, abdominal pain, and mucus to present in the stool. The latter are commonly experienced by those with food allergies.
Once you identify the food(s) that cause the reaction, the patient needs to devise ways to avoid it as much as possible. When buying food at the supermarket, read labels and look at the ingredients for foods that are known to cause a reaction. Monitor and treat any symptoms of allergies based on your physician’s advice. If you have a history of a severe allergic reaction (anaphylaxis) always keep an ‘epinephrine pen’ with you at all times. Monitor for any signs of malnutrition that may occur in children who have to avoid eating several types of food due to allergies. Consider the need to supplement these children’s food with meal replacement products rich in nutrients.
Most children outgrow their food allergies. On average, 70-87% of children are able to drink milk by age 3 and approximately 50% of children are able to eat eggs. Patients with peanut and seafood allergies are less likely to outgrow their allergy. Having a small reaction to the skin prick test and a low level of IgE on the blood test indicates that the reaction is small and that the child may outgrow the allergy.
In 2008, the American Academy of Pediatrics (AAP) Committee provided the following recommendations regarding feeding children who are at risk for developing food allergies:
If you think your child may be allergic to a certain food, please make an appointment to have it investigated.
The Second Class Honors M.D., Faculty of Medicine, Siriraj Hospital, Mahidol University, 2004.