Food Allergy or Food Intolerance
When I tell someone my child has food allergies including a dairy allergy, I have heard the response, So does my son, he is lactose intolerant. This always worries me since food allergies can life threatening, but food intolerances are not. It makes me concerned a person will not be as cautious about exposing my child to dairy as needed considering the danger involved, since they do not fully understand the difference between food allergy and food intolerance. Surveys have indicated that almost 80 percent of people who are asked if they have a food allergy and respond positively, actually did do not have a true food allergy. So what is the difference?
What defines food allergies and food intolerances?
Food allergies are an immune system response to a food that comes in contact with or enters the body. Your immune system mistakes the food as a something dangerous and starts a reaction to find the invader. The response that happens is unpredictable; it may be mild or severe. For instance, when you have a milk allergy, the bodys immune system reacts negatively to the one of the proteins in milk. With allergies, even a miniscule amount of a food can cause a severe reaction.
Food intolerances can occur due to a variety of reasons:
- Lack of specific digestive enzymes
- Malabsorption (inability to absorb nutrients or other properties of the food)
- Sensitivity to chemicals in the food
- Metabolic food disorders.
- Certain medications
- Diseases such as; viruses and bacterial infections
Some examples are; lactose intolerance (cannot digest milk due to the lack of the enzyme lactase), Favism (metabolic disorder causing an intolerance to fava beans), and salicylate sensitivity where foods with salicylates are not tolerated.
How long after eating or exposure to foods do symptoms occur?
Food allergies symptoms can occur within minutes of exposure to a food allergen; symptoms usually develop within an hour, but there are some cases when symptoms are delayed and also secondary reactions can occur.
With food intolerance the body may have a delayed reaction. Severe prolonged symptoms can develop gradually. A person may be unaware that a particular food is the reason for symptoms especially if symptoms are not digestive in nature. If you lack an enzyme, such as lactase in milk or alpha-glactosidase in legumes, digestive symptoms can occur within a short period of time.
Do more people have food allergies or food intolerances?
Four to eight percent of children have food allergies. Some food allergies will disappear during childhood, leaving about two percent of adults with food allergies.
Food intolerances are much more common that food allergies; most people are intolerant to some foods at some point in their life. For example, as many as 50 million Americans experience lactose intolerance alone.
What are the symptoms of food allergies and food intolerances?
Food allergy symptoms include:
- Hives (may vary in size)
- Redness of skin
- Swelling (face, tongue, hands, feet, etc)
- Abdominal pain
- Stomach ache
- Difficulty breathing
- Loss of consciousness
- High blood pressure
Symptoms of food intolerance are not typically life threatening immediately following ingestion like anaphylaxis. However food intolerance can effect quality of life and contribute to declining health.
Some of the more common symptoms of food intolerance are:
- Hives (urticaria)
- Irritable bowel syndrome
- Swollen or painful joints
- Nasal congestion
What are the cures and treatments available to you?
For food allergies, there are no cures or medications today. Strict avoidance of the foods is advised. There is work in the field of immunotherapy which works to build up tolerance to food allergen, but does not cure.
If there is an accidental exposure to a food allergen and a reaction does occur, treatments include immediate administration of epinephrine (EpiPen/Twinject) for severe symptoms. Also antihistamines or bronchodilators are used for milder cases. Even if treated with epinephrine, seek emergency medical help immediately by calling 911 or going to nearest emergency room.
Food intolerance refers to a wide range of digestive issues, from lactose intolerance, to food sensitivities, to stress related digestive issues, to irritable bowel syndrome and others. The treatments vary widely depending on the cause; please discuss your particular issues with your doctor.
Are there tests available to determine if allergies or intolerance exist?
For food allergies, there are two common tests. The first is a blood test, commonly called at IgE RAST test, since it is testing for the amounts of specific IgE antibodies related to reactions to certain foods. The second test often used is a skin prick test, where the skin is exposed to small amounts of foods, and then observed for reactions. Both tests can have false positives, and neither can predict the exact reactions you will have. Always have a qualified allergist help interpret the results.
Food intolerance can be difficult to diagnose, since there is no simple clear test like there is for food allergies. Intolerances can be found by elimination diets where certain foods are removed from the diet, and later introduced one at a time in a food challenge. Also keeping a journal of all food eaten can help determine the foods causing the discomfort. Elimination diets and food challenges can be done under the supervision of your physician.
Why is this important?
While food allergies and food intolerances can share some symptoms like nausea and stomach pain, knowing the difference can save your life. Even a minuscule amount of a food can cause a life threatening reaction, anaphylaxis, in some people with food allergies. Approximately 30,000 Americans go to the emergency room each year to get treated for severe food allergies, according to the Food Allergy and Anaphylaxis Network (FAAN).
If you suspect you have food allergies, see your doctor for diagnosis. Knowing what foods to avoid and carrying emergency medicine, if needed, can save your life.
- What are the most common food allergies?
- What are food allergies?
- Are food allergies increasing?
- What is anaphylaxis?
- Learn about food allergen labeling