Food allergies and intolerance continue to be a growing concern for caregivers and physicians alike. When a child presents for medical care with concern for an adverse food reaction, parents are often told their child has an allergy based on the symptoms without doing any formal testing; however, while the signs and symptoms of a food allergy or a food intolerance can be similar, there are differences making it difficult, but all the more important to differentiate between the two diagnoses.
By definition, a food allergy is an adverse health effect arising from a specific immune response that occurs reproducibly on exposure to a given food. When a specific component of food or ingredient within food is consumed that elicits an immunologic reaction, this results in symptoms that can be severe and life threatening.
Some common signs and symptoms of food allergy include:
Skin: hives, flushing, rash, eczema
Eyes: itchy, puffy, or teary with redness or swelling of the skin around the eyes
Nose: nasal congestion, runny nose, sneezing, tingling, itching
Mouth: tingling, itching, swelling of the lips, mouth, tongue, or throat
Respiratory: wheezing, shortness of breath, chest tightness, trouble breathing
Gastrointestinal: nausea, vomiting, dry heaves, abdominal pain/cramps, diarrhea
Cardiovascular: dizziness, lightheaded, fainting, irregular heart rate, low blood pressure
Nervous system: anxiety, panic, change in level of awareness
If a food allergy is suspected, your doctor should refer you to a board-certified allergist to perform testing to confirm the diagnosis of food allergy. Nutritional management will consist of omitting the allergic food in all forms from the diet and incorporating sufficient amounts nutrient-rich food alternatives.
In contrast, food intolerances are adverse health effects caused by foods. Food intolerance does not involve the immune system and is often limited to digestive problems, but can present as skin eczema, headaches, lethargy etc. Lactose intolerance is a good example of this – of the body not being able to properly breakdown the milk sugar lactose, which results in digestive discomfort such as gas, bloating, and abdominal cramping. Other common causes of food intolerance include irritable bowel syndrome and sensitivity to food additives/preservatives like sulfites, nitrates, MSG, and food dyes.
While food intolerances are not life-threatening, they can be difficult to identify due to delayed onset of symptoms that generally leave the person feeling unwell. Nutritional management of food intolerance involves identifying the food that may be causing the symptoms, determining if the food should be completely avoided or if it can be tolerated in limited amounts, identifying steps that can aid in digestion, and offering suggestions for food alternatives.
In short, if you are concerned that your child may have an allergy to a certain food, it’s important to ask for the right tests so that your response can be more precise. And as always, don’t hesitate to lean on your GIE team for more information – we’re always here for you.
by Lisa Grentz, MS, RD, CD
1. Boyce JA, Assa’ad A, Burks AW, et al. Guidelines for the diagnosis and management of food allergy in the United States: summary of the NIAID-sponsored expert panel report. The Journal of Allergy and Clinical Immunology. 2010;126(6):1105-18.