A food allergy is a type of immune system reaction you have to a specific food or substance within the food, such as protein, that can range from an irritation to life-threatening. Your immune system mistakenly attacks and releases chemicals against the food, causing the allergic reaction. Food allergies differ from food intolerances, which are abnormal responses to food, such as an inability to digest it, that do not involve the immune system.
Significance
Approximately 2.5 percent of the population in the United States has a food allergy, according to research by scientists at the National Jewish Health and University of Colorado Denver School of Medicine and published in the "Journal of Allergy and Clinical Immunology" in 2010. The research reports the estimated prevalence of food allergies is 1.3 percent for peanuts, 1 percent for shrimp, 0.4 percent for milk and 0.2 percent for egg. The research found that there is an increased risk of food allergies among males, children, African Americans and individuals with asthma. More than 300,000 ambulatory-care visits among children occur each year due to food allergies, according to the Food Allergy and Anaphylaxis Network.
Signs and Symptoms
The signs and symptoms of a food allergy normally occur within an hour after ingesting the particular food product. These symptoms include skin reactions, such as hives, itching or rash; swelling of your face or other parts of your body; difficulty breathing; abdominal pain; diarrhea; dizziness; and, in severe reactions, shock, severe drop in blood pressure, rapid pulse, loss of consciousness and death. Immediately consult a doctor or contact your nearest hospital or emergency room if you experience these symptoms after eating, especially if you were diagnosed with food allergies in the past.
Diagnosis
Diagnosing a food allergy is based on observation and trial and error with different foods. The most common foods associated with food allergies include cow's milk, eggs, soy, peanuts, tree nuts, finfish, shellfish and wheat. Research by scientists at the University Federico II in Naples, Italy and published in "Current Opinion in Pediatrics" in 2008 reports that diagnosis of food allergy involves a detailed medical history, physical examination, screening tests, and response to an elimination diet and oral food challenge. The research concludes that no single screening test, alone or in combination with other tests, can definitely diagnose or exclude a food allergy.
Prevention
There is no cure for food allergies. However, you can reduce the risks of symptoms from food allergies by avoiding the specific food items that can cause the reaction. Avoiding unnecessary or too many foods can reduce your intake of vital nutrients for health and prevention of disease. Consult your doctor about determining which foods you may be allergic to and creating a diet plan that is right for you.
References
- Food and Drug Administration: Food Allergies: Reducing the Risks
- PubMed.gov: National Prevalence and Risk Factors for Food Allergy and Relationship to Asthma: Results from the National Health and Nutrition Examination Survey 2005-2006
- Food Allergy and Anaphylaxis Network: Annual Report
- U.S. Department of Agriculture: Dietary Guidelines for Americans 2010
- PubMed.gov: The Diagnosis of Food Allergy in Children
