According to the National Institute of Allergy and Infectious Diseases, a food allergy is an abnormal response to a food, triggered by the body’s immune system. To put it simply, when a person eats an otherwise normal substance, the body mistakenly views the substance as a foreign invader. The immune system kicks into gear and sends out chemicals called histamines. Histamines can cause various symptoms of food allergies, which could be mild or life-threatening.
What Causes Food Allergies?
Food allergies have been referred to as the second wave of the allergy epidemic with asthma being the first. While scientists have not been able to determine the cause of food allergies, they have noticed a link between severe eczema and food allergies, and eventual asthma. Several hypotheses exist regarding the development and increase of food allergies, but none has been proven by medical research.
According to the Mayo Clinic, certain factors put a child more at risk for developing food allergies at some point in his or her life:
A family history of food allergies
A past food allergy. Some food allergies like those to egg are often outgrown as a child gets older, however, sometimes it will return as an allergy as an adult.
Age. Young children are more likely to be allergic to foods and may outgrow some allergies as they get older. Foods to which a child has experienced a severe reaction and allergens such as peanuts, tree nuts, fish and shellfish tend to be lifelong allergies.
Asthma and Eczema. For reasons not fully understood at this time, asthma, eczema, and food allergies seem to go hand in hand. Infants with a history of severe eczema are more at risk.
What Are the Symptoms of Food Allergies?
Food allergies symptoms may have immediate or delayed onset after eating a suspected allergenic food. If you or a family member display any of these symptoms, you should seek medical advice and avoid the suspected allergen until further testing can be done. In the case that symptoms are severe, seek immediate, emergency medical care as symptoms can become life-threatening very quickly. Individuals with diagnosed food allergies should carry fast acting epinephrine with them at all times.
According to the Food Allergy Research and Education network (FARE), food allergy symptoms can affect the gastrointestinal tract, the respiratory tract, and most seriously, the cardiovascular system. Reactions can range from mild to very severe, including a condition known as anaphylaxis.
Food allergy rash which is usually red and sometimes itchy
Hives on the skin after eating a suspected allergen
Obstruction of the airways due to swelling of tongue, mouth, throat
Shortness of breath or wheezing
Drop in blood pressure evidenced by sudden changes in personality, feeling faint or weak, confused
Loss of consciousness
A weak pulse
Sense of impending doom
These severe symptoms, by themselves or within a group of symptoms, require immediate medical treatment. According to FARE, in the United States alone, severe food allergy reactions result in an emergency room visit every three minutes.
How Will A Child Describe an Allergic Reaction?
A young child who doesn’t have the same background information as an adult will describe a food allergy differently. This is important to note because many food allergies affect young children sometimes at the first ingestion of an allergen or later after repeated ingestion. Either way, young children may be unaware of exactly what is happening to them. Be very aware of statements that seem odd and look for physical symptoms such as hives or swelling.
Statements that indicate pain such as “my tongue hurts,” “my mouth feels funny,” “there’s something stuck in my throat,” or “my throat feels thick.”
Statements that indicate itchy of the tongue, throat, mouth or ears such as “it feels like there are bugs in there,” or “it feels like there is hair in my throat.”
Statements such as the food being spicy, when it is not, can indicate a problem as well.
Children will also naturally avoid foods they are allergic to. If your child refuses certain foods, such as peanut butter or milk, do not force the issue and seek medical advice.
What Is Anaphylaxis?
Anaphylaxis refers to a series of life-threatening symptoms that occur after eating a suspected allergen. Not every food allergy reaction is classified as anaphylactic, rather the severe condition is marked by a combination of severe symptoms.
According to FARE, a reaction is anaphylactic if any one of the following three conditions is met:
The symptoms involve the skin, nose, mouth or gastrointestinal tract and either difficulty breathing or reduced blood pressure
The individual was exposed to a suspected allergen and two or more of the following occur:
Skin symptoms including swollen lips
Reduced blood pressure
Gastrointestinal symptoms such as vomiting or diarrhea
A person was exposed to a known allergen and experiences reduced blood pressure or fainting.
What Are the Most Common Food Allergies?
According to the Mayo Clinic, most food allergies are caused by the “big eight:”
Peanuts (these are actually a kind of legume that grow in the ground)
Tree Nuts (a nut that is grown on a tree such as walnuts, cashews, almonds, etc.)
Fish (sometimes called fin fish, includes flounder, tilapia, bass, flounder)
Shellfish (such as crab, shrimp, lobster)
Keep in mind that allergens are labeled differently throughout the world:
In the US, manufacturers are required to list an allergen when it is an ingredient in packaged food. Manufacturers are not required to disclose when their manufacturing processes may cause cross-contamination with an allergen.
In Europe, the Labeling Directive provides for the labeling of the big eight allergens as well as celery, mustard, sesame, lupine, mollusks, and sulfur dioxide.
New Zealand also requires that the “big eight” be labeled on processed foods.
Important precautions for those with food allergies:
When traveling internationally, be very careful about the foods you consume. Research labeling laws in your destination country and keep this information with you.
No laws require the labeling of fresh foods. Be aware of foods that are in the same family as those you know you are allergic to. For instance, someone who has tested positive to cashews is also allergic to pistachios.
When eating in restaurants at home or while traveling, discuss your food allergies with the waiter and/or the restaurant management. Be very specific about what you are allergic to and inquire as to whether or not your allergens are used in the kitchen and how your food will be prepared. Steer away from gravies and sauces where allergens can easily hide.
Food Allergy Statistics
According to reports by the American Academy of Asthma and Immunology, food allergies affect an increasing number of children worldwide, particularly in industrialized countries.
In the United States, 8 percent of children aged infant to 18 have an allergy to at least one food. More than a third of those children have a history of severe reactions and are allergic to more than one food.
In Europe, children in continental Europe are most allergic to fresh fruits and vegetables.
Food Allergy Testing
If you suspect that you or a loved one has a food allergy, what should you do? Write down the person’s symptoms including the foods suspected and the nature of the reaction. Seek the medical advice of an allergy specialist who may recommend additional testing.
Allergy testing usually is performed by a skin prick test. In this test, a small amount of the allergenic substance is placed on the patient’s skin. The technician then uses a small instrument to prick the skin at that location, introducing the allergen to the bloodstream. If a welt occurs at that location, the patient may be diagnosed with a food allergy. The specialist may prescribe fast-acting epinephrine auto-injectors to be carried with the patient at all times in case of a future reaction.