Medically reviewed by Dr. C.H. Weaver M.D. 11/2020
Cali Duke, a 28-year-old mom and account representative from Hailey, Idaho, broke out in head-to-toe hives a few years ago, she thought it might have something to do with medication she was taking for a kidney infection. But doctors tested her and found no allergy to the drug.
Even after she was finished with the medication, the hives persisted. “The hives were so bad, and I had them everywhere, even on my hands and feet,” Cali recalls. “I couldn’t put on my shoes. It hurt to walk or even get out of bed.”
A few trips to an allergist for blood testing revealed the problem: she was allergic to wheat and cocoa. It is a diagnosis that has completely changed her life.
What Exactly Is a Food Allergy?
There is a lot of confusion regarding food allergy and food sensitivity. A true food allergy involves the immune system and produces a systemic response. When a food allergy is present, the immune system produces large amounts of antibodies called immunoglobulin E in response to a protein in a certain food. This triggers an allergic response that can result in symptoms such as hives or anaphylaxis.
With food allergy even the smallest exposure to a food can produce an allergic response—and the response usually begins immediately. In other words, there are no degrees of food allergy. Someone who is allergic to a food must avoid that food at all times.
“I have to read labels on everything,” Cali explains. “Not just on food but on body lotion, hair products—everything. The chocolate is worse than the wheat. Cocoa is in a lot of things. I can’t use cocoa butter or cocoa anything.”
Of course, this attention to detail is worth it to her. “The hives were awful. I don’t ever want that to happen again,” Cali says.
Food Allergy versus Food Sensitivity
A food sensitivity—sometimes called food intolerance—does not involve the immune system. Instead it involves a reaction in the digestive system. Food sensitivity is typically related to sugars or carbohydrates in certain foods, whereas food allergy is always related to a protein.
Food sensitivity can produce symptoms such as bloating, gas, stomachache, nausea, vomiting, and diarrhea. Although these symptoms are uncomfortable, they are not life-threatening like some food allergy symptoms. What’s more, the symptoms of food sensitivity can be delayed for hours or even days. Some people even experience a cumulative effect to certain foods—they can have a little, but when they eat a lot they experience symptoms.
“Because a food sensitivity does not produce an immune reaction, it can take us longer to realize that the food we are eating is revealing symptoms to us that are unpleasant,” explains Sally Connelly, a clinical nutritionist from Tubac, Arizona.
Both food allergies and food sensitivities are a growing problem.
Food Allergies on the Rise
Cali is just one of a growing number of people with food allergies. According to a study released in 2013 by the Centers for Disease Control and Prevention, food allergies increased approximately 50 percent between 1997 and 2011.1 Approximately 15 million people in the United States have food allergies, including 9 million adults—or 4 percent of the adult population.2
?“We have research that does confirm that food allergies are on the rise. It’s a fairly recent trend that has happened mostly over the past 15 or 20 years,” explains Robert Wood, MD, director of allergy and immunology at Johns Hopkins Children’s Center. “It’s not complete information, but it’s enough to say that food allergy is twice as common now as it was 15 years ago, maybe even three times.”
There are a number of theories as to why this might be the case, but one that keeps floating to the top is the hygiene theory. “The hygiene theory says we have too clean of an environment, and if the immune system isn’t exposed to things early in life, it can turn more of its attention to allergies,” Dr. Wood says.
Dr. Wood explains that there may not be just one reason for the increase in food allergies but instead there could be five to 10 things that have contributed.
Some foods are more common allergens than others. In fact, there are eight foods that account for 90 percent of all food allergies: milk, eggs, peanuts, tree nuts, wheat, soy, fish, and shellfish.3
?Food allergies are more common in children, though some children do outgrow them. Dr. Wood explains that this tendency to outgrow an allergy differs from one food to another. For example, 80 to 90 percent of kids will outgrow an allergy to milk, eggs, or soy, whereas only 10 to 20 percent will outgrow an allergy to peanuts or tree nuts. “It requires regular testing,” Dr. Wood explains. “Some kids will outgrow an allergy fairly quickly, and others won’t outgrow it until they are teenagers.”
Cali developed an allergy in her mid twenties. “My doctor told me that anyone can become allergic to anything at any point in life,” she explains.
Indeed, adults can experience a sudden onset of food allergy symptoms, even with a food that has not caused problems in the past. The foods that most often trigger a reaction for adults are shellfish, peanuts, tree nuts, and eggs. If you have a history of other kinds of allergies, such as hay fever or animal dander, you are at a higher risk of developing a food allergy.4
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?There are a lot of myths about food allergies, too. One of the most persistent myths is that you can give yourself a food allergy by eating too much of a certain food. “That couldn’t be more wrong,” Dr. Wood insists. “You cannot give yourself a food allergy.”
Treating Food Allergies
An allergic reaction to a food usually requires immediate attention. Anaphylaxis can be fatal if not treated immediately—within minutes.5 What’s more, symptoms of anaphylaxis can recur after subsiding, so experts recommend an observation period of about four hours to ensure that the allergic reaction has been resolved.6
?Most people with severe food allergies carry epinephrine with them at all times in case of accidental exposure to a food allergen. In fact, most exposures are accidental and can be the result of mislabeling or cross-contamination during preparation. Teenagers and young adults with food allergies are at the highest risk of fatal food-induced anaphylaxis.7
?There is not yet a cure for food allergies that is ready for prime time, but scientists are working on it.
“Even though it sounds easy to avoid what you’re allergic to, it’s really not,” Dr. Wood explains. “Life would be far better if we had a way to treat food allergy so that people didn’t have to suffer reactions and have their quality of life significantly affected by having to avoid so many foods.”
Dr. Wood and other researchers are experimenting with an approach called immunotherapy, which involves exposing people to very small amounts of an allergen in an attempt to desensitize them to it. The approach is still in the experimental phase, but Dr. Wood says it could be an effective treatment strategy in five to 15 years.
Until scientists identify a surefire way to eliminate allergies, individuals with food allergies will have to remain vigilant.
Coping with Food Sensitivities
While not as alarming as food allergies, food sensitivities can be troublesome. Like food allergies, food sensitivities appear to be on the rise. The reasons for this are unclear, but Connelly believes it has a lot to do with digestion. “We don’t eat that well as a nation,” she explains. “We have impaired food digestion, and that could be one of the underlying causes of food sensitivities.”
Connelly explains that the acids and the bacteria in the stomach and the intestines are important for digestion, but we have a lot of habits that disrupt the good work they do—including overuse of medications and alcohol. “In general, we’re walking around with poor gut health,” she says.
Identifying and addressing a food sensitivity can be a complicated process—and it requires close observation. Connelly recommends starting with an elimination diet, which involves clearing out the most common allergens. “It is difficult because most people don’t want to change their dietary habits,” she admits. “You need at least a month to clear everything from the GI [gastrointestinal] tract. It doesn’t happen in just a few days.”
After the elimination diet, Connelly has clients move to a rotation diet, where they rotate one food at a time back into the diet and wait to observe any reactions. She says it is best to add one new food every three or four days and to keep a food diary and record any symptoms or changes. Often the effects of eating a food are not immediate. “You might add wheat back into the diet and feel great the first day, okay the second day, and bloated and fatigued the third day,” she explains.
Connelly says the best way to cope with food sensitivities is by promoting gut health. She recommends that people repair their gut by consuming a low-irritant, low-inflammatory diet, which means removing dairy, soy, peanuts, processed meats, shellfish, citrus, refined sugar, caffeine, alcohol, margarine, and other inflammatory foods. In fact, she refers to the “four Rs” for gastrointestinal support: remove, replace, repair, and re-inoculate. Remove inflammatory foods, replace those foods with healthy foods and digestive enzymes, repair the gastrointestinal tract with nutrients like glutamine or aloe, and re-inoculate with probiotics.
Choosing Healthy Food
Whether you suffer from food allergies or food sensitivity, there is no doubt that the food you eat has a significant impact on your overall health and well-being. “We have an epidemic of obesity and diabetes and increased food allergies and sensitivities and poor gut health, but people are becoming more aware,” Connelly says.
This growing awareness is helping promote a new commitment to nutrition and health among those affected by allergies and sensitivities and among many who may not have experienced these issues but are eager to avoid the food-related health problems. “I’m trying to stay healthy and eat right now because I don’t want to put any added stress on my body,” Cali says.
- Jackson K, Howie LD, Akinbami LJ. Trends in Allergic Conditions among Children: United States, 1997–2011. National Center for Health Statistics Data Brief. 2013. Available at www.cdc.gov/nchs/data/databriefs/db121.htm. Accessed October 2, 2013.
- National Institute of Allergy and Infectious Diseases, National Institutes of Health. Report of the NIH Expert Panel on Food Allergy Research. 2006. Available at niaid.nih.gov/topics/foodallergy/research/pages/reportfoodallergy.aspx. Accessed October 2, 2013.
- Bock SA, Atkins FM. Patterns of food hypersensitivity during 16 years of double-blind placebo-controlled food challenges. Journal of Pediatrics. 1990;117(4):561-67.
- NIAID-Sponsored Expert Panel. Guidelines for the diagnosis and management of food allergy in the United States: report of the NIAID-sponsored expert panel. Journal of Allergy and Clinical Immunology. 2010;126(6 Suppl):S1-S58. doi: 10.1016/j.jaci.2010.10.007.
- Bock SA, Muñoz-Furlong A, Sampson HA. Further fatalities caused by anaphylactic reactions to food, 2001–2006. Journal of Allergy and Clinical Immunology. 2007;119(4):1016-18.
- Ellis AK, Day JH. Incidence and characteristics of biphasic anaphylaxis: a prospective evaluation of 103 patients. Annals of Allergy, Asthma, and Immunology. 2007;98(1):64-69.
Bock SA, Muñoz-Furlong A, Sampson HA. Fatalities due to anaphylactic reactions to foods. Journal of Allergy and Clinical Immunology. 2001;107(1):191-93.
Celiac Disease versus Gluten Sensitivity
Contrary to popular belief, celiac disease is not a food allergy. It is an autoimmune disease that causes damage to the small intestine, which interferes with the absorption of nutrients from food and triggers an abnormal immune response to foods containing gluten.
Celiac disease affects the villi, which are small, fingerlike protrusions that line the small intestine. The villi are supposed to allow nutrients from food to be absorbed into the bloodstream, but with celiac disease the immune system destroys or damages the villi when gluten is ingested. As a result, it is impossible for a person with celiac disease who eats gluten-containing foods to be properly nourished, as the digestive system cannot absorb nutrients in food. Gluten sensitivity refers to a condition in which one cannot tolerate gluten and may experience bloating, diarrhea, fatigue, headache, and brain fog. Gluten sensitivity does not involve the autoantibodies or damage to the small intestine.