Do You Have Meat Allergy? - Allergic Diseases

Meat Allergy

Food allergies are very common in the developed world, affecting up to two percent of adults and eight percent of children. While people can have allergic reactions to pork, beef, lamb, game, or poultry, meat allergy is a less common cause of food allergy compared to peanuts, tree nuts, soy, wheat, cow's milk, eggs, shellfish, and fish. Childhood meat allergy is usually associated with atopic dermatitis and outgrown during the first years of life. Meat allergy can also develop in adulthood.

Red Meat Allergy

Red meat allergy, also called as alpha-gal allergy or mammalian meat allergy (MMA) that occurs most frequently in people with an A or O blood group type. According to researchers, this is because the B antigen in AB or B blood types most resembles the allergen that triggers a meat allergy, providing those individuals with innate protection.

With regards to beef, lamb, pork, and other mammalian meats, the allergen in question is sugar, specifically, a type is known as alpha-gal sugar found in almost every mammal except for humans. While an A or O blood type may increase a person's risk of a meat allergy, research suggests that certain infections or co-existing allergies may trigger a symptomatic response or amplify its effects.

One of the most common triggers are the bite of a lone star tick (named for these single white marking on its back). Found primarily in the Southern and Central United States but expanding elsewhere, the lone star tick—also known as a turkey tick or northeastern water tick— sucks blood from mammals whose meat contains alpha-gal sugar. When the tick feeds on a human, it introduces those sugars into the bloodstream, sensitizing the person to alpha-gal.

Causes

A meat allergy can develop at any phase throughout everyday life, and certain people are at greater risk including those with specific blood types, tick bites, past infections, atopic dermatitis, or co-existing food allergies.

As with all allergies, the underlying cause, and cure of a meat allergy are unknown. With that being said, scientists have gained greater insights into the key factors that trigger red meat allergies and poultry allergies, respectively.

The unusual thing about meat, allergies are that the delayed reactions can be every bit as severe. With almost every other type of food allergy, a delayed response is typically manageable. Not so with a red meat allergy for which anaphylaxis can occur many hours after the meat has been consumed.

Diagnosis

A meat allergy is usually suspected if you experience any symptoms whenever you eat certain types of meat. To confirm your suspicions, you would need to see a specialist known as an allergist who can to perform a series of common allergy tests. 

These include:

An allergy blood test that able to distinguish antibodies, known as immunoglobulin E (IgE), particular to the different types of meat or poultry. 

A skin prick test in a which, small amounts of meat protein are put underneath the skin to see if any trigger a skin reaction. 

An elimination diet to expel  suspected meat allergens from your diet to see if the symptoms improve.

Less commonly, an oral challenge may be done to introduce certain meats into the diet to see if they trigger a reaction. This would only be considered if your symptoms are mild and conducted under the strict supervision of a board-certified allergist.

Treatment

The best form of treatment for a meat allergy is the avoidance of the specific meat or meat by-products this includes checking all food labels (particularly sausages, pâtés, and other mixed-meat products) and restaurant ingredients whenever dining out. If the meat is a major staple of your diet, you should consider meeting with a dietician who can help you find alternate sources of protein while ensuring you meet your daily nutritional needs.

If you accidentally eat problematic meat and have an uncomplicated reaction, an over-the-counter antihistamine will often help relieve rash or mild respiratory symptoms. A corticosteroid nasal spray can also be used to open blocked nasal passages. People with asthma will typically need a rescue inhaler to ease respiratory distress.

However, if you have experienced a severe reaction in the past or are at risk of anaphylaxis, you need to carry an EpiPen to inject yourself with epinephrine (adrenaline) in an emergency situation. Anaphylaxis always requires emergency, in-hospital care, usually with intravenous (IV) corticosteroids, antihistamines, and IV fluids.

Some scientists suspect that meat allergies are far more common than presumed, with some cases of anaphylaxis believed misattributed to other more common causes, such as a nut or shellfish allergy. To this end, it is important to speak with your doctor if allergy symptoms persist despite the exclusion of a presumed food allergen. This is especially true in areas where the lone star tick is endemic.