On Food Allergies and Intolerances

Individuals may experience allergies to any number of substances, but reports indicate that a growing number of Americans suffer from allergies to particular foods. Food allergies affect approximately 12 million Americans, including three million children. ”Food intolerances,” though frequently discussed in conjunction with food allergies, are quite different. Individuals with “intolerance” to certain foods may experience adverse reactions and discomfort if they are consumed. It is important to have an understanding not only of the severity and potential risk of food allergies, but of the difference between true allergies and intolerances.

The majority of adverse reactions linked to particular foods are due food intolerances. Individuals can be intolerant to lactose, gluten, or other foods, and may experience nausea, vomiting, stomach cramping, and diarrhea. While these symptoms are surely unpleasant, they are markedly different from the immune response seen in individuals with food allergies. In addition to bowel discomfort, food allergies can cause an anaphylactic response, leading to tingling and swelling of the mouth and face, hives, trouble breathing, dizziness, or fainting. These symptoms are caused by an response in which the body’s immune system mistakenly identifies a particular food as a harmful substance. An allergic reaction involves two components of the immune system: an antibody called immunoglobulin E (IgE), and a mast cell. When an individual consumes - or in some cases is in close contact with - a food to which they have an allergy, the allergen stimulates specialized white blood cells called lymphocytes which produce the IgE antibody for that specific allergen. This IgE is then released and attaches to the surface of the mast cells in the tissues of the body, prompting the cells to release histamine.

Allergic reactions can range in severity, but reports indicate that they cause 30,000 cases of anaphylaxis, 2,000 hospitalizations, and 150 deaths each year in the United States. According to the U.S. Centers for Disease Control and Prevention (CDC), there are eight foods which account for 90 percent for all food-allergy reactions: cow’s milk, eggs, peanuts, tree nuts (walnuts, pecans, etc.), fish, shellfish, soybeans, and wheat. One of the most common food allergies in the United States is to peanuts, affecting an estimated 3.3 million Americans. The incidence of peanut allergies is increasing, and reports indicate that between 1997 and 2008, the rate of child peanut allergies has tripled. Rates of other food allergies have also increased in recent years, and according to the CDC, the number of children with food allergies increased by 18 percent, between 1997 and 2007. While the cause of the increase is not fully understood, it may be due in part to the risk factors associated with food allergies, which include a family history of asthma and allergies, and elevated IgE levels.

Though there is no proven treatment for food allergies other than the avoidance of the allergen, experts recommend that individuals with food allergies carry injectable epinephrine at all times, as it can help to mitigate severity of the allergic response. In addition to the physical health-related issues resulting from food allergies, reports indicate that more than 30 percent of children with food allergies have experienced teasing or bullying related to their allergy. By gaining an understanding of food allergies and sharing information about them with others, it may be possible ensure that individuals are better informed about how to help prevent allergic reactions, and lessen the stigma faced by children with food allergies.

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