Do you know the difference between a food allergy and food sensitivity? Do you know what to do if you see someone having an anaphylactic reaction? These are just a few of the important questions we had for Candis Wenger of Allergy Partners.
What are the signs of a food allergy?
Symptoms differ from person to person, can range from mild to severe, and a person can have different symptoms each time he or she has an allergic reaction. Food allergies can cause rashes, such as hives and eczema; stomach problems, such as diarrhea; and in severe cases anaphylaxis, which is a life-threatening reaction. Most allergic reactions happen within [a few] minutes to a few hours after eating, or rarely, touching the food.
What are the most common food allergies?
In children, the most common food allergies are milk, soy, wheat, egg, peanut and tree nuts. In older children and adults, shellfish and fish are additional allergens.
Are food allergies becoming more common? We hear about them so often now in the news.
There appears to be an increased incidence of allergies in general, including food allergies. However, many reactions that are called allergic by the general public are not truly food allergies. As we understand more about the way food can cause problems, we are able to differentiate and diagnose true food allergies more readily and more accurately.
What are the differences between a food allergy, food sensitivity and food intolerance?
A food allergy is an immune response to a food. In other words, an allergic antibody (IgE) is formed and directed against various proteins of the food. The allergic antibody is attached to allergy cells in the body that contain products such as histamine (and many others) that are released when the allergy antibody comes in contact with the protein from the food. The reaction is very quick — within 30 minutes or less of eating the food. The reaction can be reproduced by a skin test, and the amount of allergy antibody can be measured by a blood test. Typical effects of the allergic reaction can include hives, itching, vomiting, stomach pains, diarrhea, breathing difficulties, throat swelling and sometimes fainting.
A food sensitivity represents an alternative mechanism for reacting to a food. Sometimes there can be a deficiency in the enzymes needed for proper digestion as is seen in lactose intolerance. There can be other metabolic disorders that can cause food sensitivities such as G6PD deficiency. Some intestinal disturbances can limit tolerance to certain foods as is seen in Celiac disease. Irritable bowel, Crohn’s disease, ulcers, gall bladder disease, et cetera are examples of conditions that will make an individual intolerant or sensitive to different foods. These sensitivities and intolerances are not able to be demonstrated by skin testing and are not allergies in the true sense of the word. Nevertheless, if a food is a consistent cause of a reaction it should be avoided. The ultimate determinant if a food should be ingested is what happens when you eat it.
Are all food allergies potentially life-threatening?
The prevalence of food allergies has increased at an alarming rate over the past 20 years. The percentage of children diagnosed with food allergies increased from 3.4 percent from 1997-1999 to 5.1 percent of all children in the years 2009-2011. Food allergies have been shown to affect 6-8 percent of 1 year olds with some studies estimating the prevalence of food allergies in the first year of life at 10 percent.
Not all food allergies are necessarily life-threatening. Itchiness or irritation of the mouth, lips and tongue after ingesting a fresh fruit or vegetable is often a marker of severe pollen sensitivity. The development of hives and/or swelling within minutes of ingesting a food is the most common presentation of a food allergy. Other symptoms including nausea/vomiting, diarrhea, abdominal cramping, uterine cramping, wheezing, shortness of breath and loss of consciousness can also occur.
The initial manifestation of a food allergy may be relatively mild, such as the development of hives, in some individuals. However, subsequent exposures to the same food may result in more severe symptoms. Those with a suspected food allergy should consult with an allergist for testing in order to confirm the diagnosis and develop a treatment plan in the event of future accidental exposures.
What is anaphylaxis? What should I do if someone around me is having an anaphylactic reaction?
Anaphylaxis is the term we use to describe a serious allergic reaction. It can happen very quickly and can be life-threatening. Anaphylaxis can happen from exposure to a food, medication, materials such as latex, or insect sting. Anaphylaxis can involve one or more parts of the body. The most common symptoms are:
• Hives (raised, red patches of skin that are very itchy)
• Swelling and puffiness (usually of the face, eyelids, ears, mouth, hands, or feet)
• Redness or itching of the skin (without hives)
• Swelling or itching of the eyes
• Runny nose or swelling of the tongue
• Trouble breathing
• Wheezing, change in your voice, throat tightness,
• Throwing up, stomach cramps, diarrhea,
• Dizziness or fainting, if blood pressure drops.
If someone around you has these symptoms call 911 and see if they have a medic alert bracelet and epinephrine autoinjector on them (i.e. Epipen). Most autoinjectors have the instructions for proper use on them and the 911 operator should be able to talk you through use as well.
Do you have questions for Allergy Partners? Ask them live on our Facebook page during Ask The Expert January 14, 2016!