It has been calculated that allergies to 8 different foods lead to about 50-90% of allergic reactions. Here is the list of allergens that cause the most common food allergies in the United States:
- Tree nuts
Various people and organizations will list them in different orders, but usually the same 8 show up. Not everyone actually agrees and if you search the internet you will see various lists to choose from, but the top 8 are almost always on the lists, even if there are multiple other items on the lists. Some people have tried to break down the categories into specific tree nuts or they have tried to make multiple categories of wheat versus gluten. You must read their definitions very carefully.
The most common food allergies in adults are shellfish and seafood, in U.S. adults. Dairy and milk lead the list for allergens in children. Peanuts and tree nuts cause the most fatal or near fatal reactions in the United States. As adults age, they can develop lactose intolerance because they lose the enzymes in their bowel needed to digest lactose. This is not the same as a milk allergy in a child. Even though wheat and gluten allergies are the big news makers today, they do not account for as many allergies as one might think. Many people may have gluten intolerance, but celiac disease remains relatively rare.
Allergy versus intolerance—is there really a difference?
An intolerance may feel like an allergy, but by definition they are not the same. Allergies will come on suddenly while intolerance could take hours to even days to surface. With an allergy only a small amount of exposure brings on the response. With an intolerance it may take a certain amount or more to create symptoms though sometimes only a small amount brings on symptoms.
Allergies can be life threatening but intolerances can only be highly annoying. Anaphylaxis is a very strong allergic response to something that creates swelling in the throat which can affect ability to breath and a large drop in blood pressure. Medical care is needed immediately if a person starts into an anaphylactic reaction. An Epi-pen can help, but the person still needs medical care because the first part of the reaction may not be the only part.
A food allergy or intolerance can share symptoms which can make it difficult to decide which of the two problems you actually have. Nausea, stomach pain, diarrhea, and vomiting can occur with either. Intolerance can include developing gas, indigestion, cramps and bloating as your body struggles to digest the food. Over time you may also experience anxiety, become irritable, or develop a headache.
With a true allergy your immune system misreads a protein in a food as a “bad invader” and attacks this ‘allergen‘. A whole body reaction occurs which could include developing a rash or hives anywhere on your body, itchy eyes, or nasal congestion. Your face, mouth and throat could swell mildly. If it swells more than mildly you may be on the way to an anaphylactic reaction.
How to determine what the allergen is
Sometimes the allergen is not in doubt, due to a large and often fast reaction to it. Most times it is prudent to have allergy testing done so that other allergens can be found. Testing can be done through the skin prick test. A small amount of different fluids containing various allergens are dotted on the skin and lightly pricked into the skin. If a histamine release (redness and swelling) occurs around the spot it indicates a positive response. Blood testing for IgE antibodies against various proteins can be used instead or along with the skin testing.
Common food allergies in children
A 2009 review published in the journal Pediatrics found that almost 4 percent of American children report a food allergy. This was approximately an 18 percent increase in 10 years. Dairy and eggs are the most common allergens in children in the United States. The most common reaction is a skin rash or hives. Food allergies will differ by the area you look at because they will always be related to the diet of the people in the region. In Taipei the top allergen is crab and in Israel there are higher rates of sesame allergy than with children in the U.S.
Allergy symptoms in babies can include hives, flushed skin, rash, face, tongue or lip swelling, vomiting or diarrhea, coughing or wheezing, and difficulty breathing. Remember that any food allergy symptoms are important because the allergy can worsen with time and allergic reactions can vary from one time to the next.
Eczema, also known as atopic dermatitis, is a chronic skin rash associated with an irregularity in the child’s immune system. It is one of the key symptoms that babies and children develop when exposed to allergens and it affects about 20 percent of children in the U.S. No matter whether the allergen can be pinpointed or not, treatment of eczema focuses on keeping the skin moist
Food intolerances in child may be expressed as a dislike to a specific food. The child could experience an unpleasant sensation, such as an itchy mouth, but really can’t convey the problem beyond showing a dislike for the food.
There is some evidence to support the idea of introducing “risky foods” to children at an early age, unless there is a family history that would indicate otherwise. Early exposure may make your child less likely to become allergic to the food. It may be best to wait until about 9 to 10 months before introducing new foods because an allergic reaction can be better managed in an older baby. Whole cow’s milk should only be given to babies who are 1 year or older because the proteins in whole milk can irritate the stomach.
Children can outgrow their allergies to milk, eggs or wheat by the time they are 6 years old. About 80% will do so. About 20% of children with peanut allergies will outgrow the allergy by the age of 6. Adults will rarely outgrow an allergy over time.
What about celiac disease and gluten sensitivities?
Celiac disease, also known as gluten sensitive enteropathy, is an autoimmune disease. When a person eats gluten containing foods such as wheat, rye or barley the small intestine becomes inflamed and damaged. The body responds by attacking its own bowel wall as though it is the enemy.
Gluten intolerance or sensitivity is not the same as having celiac disease. The body’s immune system reacts in a different way that does not damage the lining of the small intestine. It still creates inflammation but this time it involves bowel, joints, skin and/or muscles. Fatigue, headaches and depression can occur. The person is not as sick as someone with celiac disease but will still feel best if they avoid gluten, and many gluten-free recipe options are now thankfully available.
There are many foods that can cause allergies (note the difference to intolerance). However the top 8 we have listed account for the majority of instances among them. It is important to note that ANY food has the potential to cause an allergic reaction, so bear this in mind.
You will find much more information on these throughout the site.