One thing is clear. Food allergies are on the rise in the U.S. and in most western countries for reasons that are unclear. There is a fair amount of confusion about food allergies and why they are more prevalent. True food allergies are triggered by a protein in the respective food that provokes a strong reaction by the immune system. A reaction can occur in only a few minutes or up to a few hours after ingestion of the food. Skin reactions like profound itching, rash or hives are present with food allergies 90% of the time. Wheezing and shortness of breath are also very common. Nausea, vomiting or diarrhea is much less common. Severe reactions can progress rapidly in children or adults. Significant food allergies usually begin within two hours after ingestion of the food. Anaphylaxis, the most severe form of allergic reaction, can progress rapidly and be profoundly dangerous without prompt medical attention.
Food poisoning from eating tainted or contaminated food is much more common and is easily confused with a true allergy. Food poisoning is typically a one time event that is not reproducible. It can occur as a mini-epidemic affecting more than one person at a time although a single person can obviously be the only victim. Individual reactions to food like a migraine after eating chocolate is not an allergic reaction. Lactose intolerance manifested by cramping and diarrhea after eating dairy products is not an allergy. An adverse reaction to a number of different foods or processed food ingredients is not a true allergy.
Although peanut is the allergen most often associated with severe or fatal reactions, any food has the potential to cause anaphylaxis. The most common food allergies in childhood are milk, egg, and peanut. Most children outgrow their milk, egg, wheat or soy allergies. The most common food allergies in adulthood are peanut, tree nuts, fish and shellfish. Peanut allergies tend to last a lifetime. In recent years more attention to food manufacturing practices and labeling have acknowledged this problem. Many variables can affect the severity of food allergies. How a food was prepared, the amount ingested, presence of an acute or chronic illness, medications, alcohol, or even exercise can affect a reaction. There can be other mitigating circumstances. Severe reactions do not usually occur from mere touching a food, nor from the smell of food. Ingestion is necessary. However steaming or roasting the food product so it was aerosolized could create enough exposure in selected individuals through inhalation.
Confirming a reaction as allergy to a specific food can be difficult. The history of a reaction within the appropriate amount of time is probably the most helpful clue. Both skin and blood tests have some problems. Although they can be very sensitive in detecting an allergy they do not correlate to the specific reaction more than half of the time. A negative test is more valuable that there is not a true allergy, but not a guarantee. The predictive value of a positive test is murkier and must be correlated carefully with the history. Consulting your health care provider or an allergy specialist may be necessary to sort this out. As there is no cure for food allergies, prevention relies largely on avoidance of the particular offending food.
After many years pediatric experts recognized that food allergies have continued to rise in spite of recommendations to avoid highly allergic foods during the first 1 to 3 years of childhood. Research has left a difference of opinion about how to best avoid allergic problems in children. Some experts suggest introducing small amounts of foods such as peanuts at an earlier age. Some think that regular small amounts may allow the individual to acclimate to the food in question. At this point there is no consensus about when and how much is appropriate. Going slowly and being a patient parent when it comes to introducing new foods to your young child seems sensible. There is no evidence that delaying foods makes a difference in allergic reactions once a child is older than six months and is physically mature enough to handle and swallow soft or thick food products. Family history of reactions may be a clue of what to expect in your young child. Adults or children who demonstrate other conditions related to hypersensitivity such as eczema and asthma may be more likely to have food allergies.
Understanding the hallmarks of severe allergic reactions and how to get prompt medical attention remain very important. Thoughtful attention to dietary challenges is the key to avoidance in allergic individuals. Consult your health care provider to maintain balanced nutrition in your diet. Food allergies need not cramp your style too much.
