People often get sick after eating and diagnose themselves with a food allergy. That's part of why more than 20% of Americans believe they have a food allergy when really only an estimated 2.5% actually do.
Why the discrepancy? Not all adverse reactions to food are due to allergies. Read on to learn about some of the conditions that can mimic food allergies. Then, find out more about how food allergies are diagnosed in Food Allergy Diagnosis and Diagnosing Food Intolerances.
As always, if you're concerned about uncomfortable or ongoing symptoms, please call your doctor for advice.
What It Is: A deficiency in an enzyme that helps the body break down lactose sugar, which is found in cow's milk and other ruminant milks (sheep, goat, etc.).
Symptoms: Bloating, gassiness, diarrhea, and gastrointestinal distress after eating milk, cream, ice cream, and other dairy products. Some people with lactose intolerance do tolerate cheese, yogurt, or small amounts of unprocessed dairy.
Treatment: Supplements of lactase enzyme help the body break down lactose sugar.
What It Is: An autoimmune disorder characterized by an inability to digest gluten, a protein found in wheat, rye, and barley. Some celiacs react to avenin, a related protein found in oats.
Symptoms: Often constipation, diarrhea, or cramping after eating foods containing gluten, though symptoms vary widely. Dermatitis herpetiformis, an itchy skin rash that can resemble hives, is common among celiacs.
Treatment: A strict gluten-free diet is the only treatment for celiac disease, though steroids are sometimes used to help heal the intestine in the early phase after diagnosis.
What It Is: A disorder of chronic abdominal pain and disordered bowel function. It may be aggravated by certain foods.
Symptoms: Constipation, diarrhea, and abdominal pain are the three main symptoms of IBS.
Treatment: Among the treatment options for IBS are drug therapies, nutritional changes, psychotherapy, and stress management techniques.
What It Is: Crohn's disease is the most well-known of a group of conditions known as inflammatory bowel disease. (Ulcerative colitis is another condition in the same group.)
Symptoms: In addition to gastrointestinal symptoms such as diarrhea, nausea, and abdominal pain, Crohn's disease can cause fever, skin and eye irritation, and rectal bleeding.
Treatment: A variety of medications, several surgical procedures, and dietary changes are all used to treat Crohn's disease.
What It Is: Histamine isn't just found in the body; some foods -- especially aged or fermented foods -- have naturally high concentrations of histamine too. Some people are highly sensitive to histamine in foods, often due to low levels of certain enzymes in the body that metabolize histamine.
Symptoms: Migraine headaches, gastrointestinal symptoms, and common allergy symptoms such as hives, rhinitis, and eczema are among the most common histamine intolerance symptoms.
Treatment: A strict histamine-free diet is the accepted treatment for histamine intolerance, though antihistamines may be of some help in case of accidental ingestion of histamine.
What It Is: Food poisoning is usually fairly easy to recognize, but toxins in tainted seafood can cause unusual symptoms you may assume are allergies, especially since fish and shellfish are common allergens.
Symptoms: Toxins in seafood can cause gastrointestinal symptoms, hives, redness, headaches, breathing difficulty, and neurological symptoms like temperature confusion and short-term amnesia.
Treatment: IV fluids for dehydration and medication to treat vomiting. Antihistamines may be used to treat scombroid poisoning, caused by tainted fish that have high levels of histamine.
Source: Kurowski, Kurt, and Robert Boxer. "Food Allergies: Detection and Management." American Family Physician. Jun. 2008 77(12): 1678-86.
Kurowski, Kurt, and Robert Boxer. "Food Allergies: Detection and Management." American Family Physician. Jun. 2008 77(12): 1678-86.