Alpha-Gal Syndrome and Meat Allergy

Man laying on his couch holding his abdomen in discomfort.

Can you be allergic to meat? The answer is yes, and it can be life-threatening. This allergy is known asalpha-gal syndrome, commonly called red meat allergy. It can affect people who eat beef, pork, bison, lamb, venison and/or goat.

How does this happen? You get bitten by a tick (usually the lone star tick) and that bite transfers alpha gal, a type of sugar molecule found in your body. Your immune system then develops a response to this molecule. When you eat products that contain alpha gal, you have an allergic reaction.

Foods that contain alpha gal are red meat or meat from mammals, and products that are made with them (including milk and gelatin). Alpha gal is not found in fish, birds (including chicken) or humans.

You can be allergic to meat – specifically red meat – but only under certain conditions. Commonly called red meat allergy, oralpha-gal syndrome(AGS) after the blood carbohydrate involved in the allergy, the condition is connected to a recent tick bite.

You may hear red meat allergy also referred to as mammalian meat allergy, lone star tick disease or tick bite meat allergy.

Alpha-gal syndrome is reportedly on the rise. In 2019, there were approximately 34,000 people in the United Statesdiagnosed with alpha-gal syndrome. Cases have also been discovered in Europe, Asia and Australia.

Chart of Alpha-gal syndrome progression from Tick to tick bite to consuming meat or milk to the reaction. This takes about 1-3 months for symptoms to appear.

What is alpha-gal syndrome?

AGS is a red meat allergy caused by a tick bite. The alpha gal sugar molecule is found in a tick’s saliva. Soon after the tick bites you, it causes an immune system response that increases your sensitivity to red meat. The allergic reaction usually occurs hours after eating a meal with red meat.

Is alpha-gal syndrome also lone star tick disease?

Some refer to the condition as the lone star tick disease. It is thought that AGS is caused by a bite from thelone star tick, but species of ticks in other parts of the world can also cause the condition.

The lone star tick is most prevalent the eastern and southeastern regions of the United States. It can be found as far west as Texas and New Mexico and as far north as Maine.

Alpha-gal syndrome was first discovered in 2009. Since then,alpha-gal syndrome caseshave been reported in Australia, Germany, Sweden, Japan, and South Africa.

Woman sitting at her desk feeling nauseated and holding her belly.

What are alpha-gal symptoms and meat allergy symptoms?

First you must identify the tick bite. This can be hard because these critters are small and difficult to find. They often attach themselves to the leg, groin, back of the neck or the scalp. Many people only experience a rash that itches longer than normal. There may also be a small, hard bump under the skin where the tick bit you.

Ticks that transfer alpha-gal sugar molecule can cause red meat allergy. AGS allergy symptoms are similar to other food allergy symptoms, but with more gastrointestinal distress. Signs of an AGS allergic reaction may include:

  • Hives or itchy rash
  • Gastrointestinal problems (GI symptoms)
  • Nausea or vomiting
  • Heartburn or indigestion
  • Diarrhea
  • Severe abdominal pain
  • Cough, shortness of breath, or trouble breathing
  • Swelling of the lips, throat, tongue or eyelids
  • Dizziness or fainting
  • Low blood pressure

The allergy can cause anaphylaxis – a potentially life-threatening allergic reaction involving more than one organ system at a time. But this is rare.

Doctor sitting at desk with patient, and she is giving the woman a consultation.

How is alpha-gal syndrome diagnosed?

AGS is diagnosed by an allergist or other healthcare provider. The physician will…

  • take a thorough health history;
  • perform a physical exam;
  • order a blood test to check to see if your immune system has developed antibodies to alpha-gal.

AGS is sometimes hard to diagnose because symptoms are often delayed 2-6 hours. (Most food-allergic reactions occur within a few minutes of consuming an allergen, but with AGS, it’s often delayed.) You may eat a steak for dinner but not develop symptoms until nearly midnight.

Alpha-gal allergy treatment

People with AGS should also always carryepinephrineauto-injectors in case of a severe or life-threatening allergic reaction, also called anaphylaxis. Epinephrine should be givenfirstandfastto treat anaphylaxis.

Like other food allergies, avoidance of the trigger food is the key to preventing symptoms. It is critical for people with AGS to avoid eating red meat and any other meat products that contain the alpha-gal sugar molecule.

Alpha-gal syndrome prevention

The best thing you can do to avoid AGS is prevent tick bites. Here are some strategies to avoid tick bites:

  • Know your environment.Do your best to avoid ticks. They like bushy, grassy and wooded areas. If you frequent these areas in your yard, on walks or hikes, or through your work, you are at higher risk for tick bites.
  • Cover your skin. Wear long sleeves and pants so you don’t have exposed skin. To be extra cautious, tuck your socks onto your pants.
  • Tick proof your clothing and gear. Products with 0.5% permethrin can be used to pre-treat clothing and gear.
  • UseEPA-recommendedinsect repellents or a bug spray.
  • Do a regular tick check. After being outside, check yourself and your pets for ticks – particularly in dark crevices such as behind ears, in the belly button, in underarms, and the groin.
  • Shower and wash your clothes after being outside.

The more often you are bitten by ticks, the higher your risk for developing AGS. Preventing tick bites can also help protect you from other tick-borne diseases like Lyme disease and Rocky mountain spotted fever.

Big juicy thick steak cooked with herbs and spices.

Are there alpha-gal foods to avoid?

Since trigger avoidance is key with AGS, it is important to avoid foods containing alpha-gal. This meansmost types of red meatand related products. These foods include:

  • Red meat from mammals (including beef, pork, lamb, venison, rabbit, bison, buffalo and other meats); organ meats such as livers, hearts, brains and intestines contain the highest amounts of alpha gal
  • Cow’s milk or cow’s milk products (ice cream, yogurt, etc.)
  • Gelatin made from beef or pork
  • Products made from or cooked with mammalian fat (such as lard, tallow or suet)
  • Meat broth, bouillon, stock and gravy
  • Gummy candies, marshmallowsand some other candies that may contain derivatives of alpha gal

However, just because a food contains alpha-gal doesn’t mean you will have a reaction. So, some people with AGS may be able to tolerate milk and other products. So, it is important to work with a board certified allergist.

What’s a good alpha-gal allergy diet?

If you’re living with AGS, you likely require dietary restrictions to avoid symptoms. That doesn’t mean you need to become vegan or vegetarian. You just need to be aware of and avoid foods that contain alpha-gal.

You can still eat poultry (chicken, turkey), eggs or fish as part of your diet. Fresh fruits and vegetables are safe and a great source of nutrients.

Can you eat eggs with alpha-gal allergy?

Yes, you can eat eggs with AGS. Eggs come from poultry such as chicken or ducks. Poultry does not contain alpha-gal, so it is safe to eat eggs if you have AGS.

What about alpha-gal and alcohol?

Alcohol does not contain alpha-gal. However, people with AGS who eat red meat (or other alpha-gal foods) and alsorecently consumed alcoholmay develop more severe symptoms.

Is there a cure for alpha-gal syndrome?

There is no cure for alpha-gal syndrome. If you’re diagnosed with AGS, the best way to avoid an allergic reaction is to not eat red meat. People with AGS who accidentally eat red meat should carry an epinephrine auto-injector, the best treatment for severe allergic reactions. The good news is that AGS is not a lifelong condition.

问题&答案(问答)肉过敏

You may have specific questions about alpha-gal syndrome. Here’s a Q&A with some common questions about this condition. If there’s a topic you’d like to see answered in this Q&A, please emailGary Fitzgerald, Senior Editor

How long after a tick bite does alpha-gal develop?

People tend not to develop AGS soon after the tick bite. They may notice that the skin around the tick bite itches longer than normal – 10 days or so. But it can take up to 3 months foralpha-gal syndrome to develop.

This is a another reason why diagnosis is challenging – you may not even remember having a tick bite.

How common is alpha-gal syndrome?

Cases of alpha-gal syndrome are on the rise. Between 2010 and 2018, approximately 34,000 people in the United Statestested positive for alpha-gal syndrome. The highest percentage of people who tested positive were in Arkansas, Virginia, Kentucky, Oklahoma and Missouri.

AGS is also the leading cause ofadult-onset of allergy and anaphylaxis.

Are meat allergy symptoms in adults the same as children?

Children and adults develop the same symptoms of AGS. The most common symptoms involve hives and gastrointestinal problems. Adults aremore likely to have an anaphylactic reactionto alpha gal than children.

Are there meat allergy home remedies?

No, there are no home remedies for AGS. The best action to prevent a meat allergy is to avoid tick bites. If you already have the condition, then avoid eating any meat products containing alpha gal.

What tick diseases cause meat allergy?

Red meat allergy is only caused by the introduction of the sugar molecule alpha gal into your body. It is not caused by an infection. Other tick-borne diseases such as Lyme disease and Rocky Mountain spotted fever do not cause a sensitivity to meat.

What’s the most important thing the public needs to know about red meat allergy?

Alpha-gal syndrome is a delayed reaction: symptoms can happen hours after eating meat. People often don’t think it’s a food-allergic reaction. This is very different from a typical food allergy in which symptoms usually occur immediately after eating a food allergen.

If you get a tick bite, should you automatically avoid meat for a while?

No. The chances of getting red meat allergy are still quite low. Studies have identified the groups at highest risk. Largely it’s hunters, gardeners and others who spend a lot of time outdoors in tick areas.

Watch for AGS symptoms if you get a tick bite. If you experience an itchy rash or hives and/or stomach problems, then you may want to hold off on eating red meat until you can get tested.

Can you trigger the allergic response through cross contamination with a serving spoon, or kissing someone who has just eaten a burger?

Most people with AGS experience symptoms only after eating a major cut of meat. They do not typically develop allergy symptoms due to cross contact with other foods or utensils; or casual contact with someone who is consuming red meat.

Is alpha-gal syndrome a life-long condition?

AGS does not appear to last forever. However, additional tick bites can boost your level of sensitivity, so if you’re someone who goes outdoors and gets tick bites 4-5 times a year, it may be hard for the meat allergy to go away. Others may be fine within 20-24 months. However, the allergy could return with another tick bite.

Reviewed by:
Jacqueline Eghrari-Sabet, MD, FACAAI,is board-certified in allergy, immunology and pediatrics. She is the Medical Director of Telehealth for Allergy & Asthma Network. Dr. Eghrari-Sabet is the founder of Family Allergy & Asthma Care and the FAAR Institute in the Washington, DC area, where she has been in private practice since 1994. Dr. Eghrari-Sabet is Assistant Clinical Professor at George Washington University School of Medicine and Health Sciences where she mentors the next generation of doctors. She is also President of White Coat Resources, a health education consulting service.

Other conditions that may look like food allergies or co-exist with food allergies?

There are other conditions that are different than food allergies but the symptoms, diagnosis and treatment vary depending upon the condition. Here are some of them.

Food Intolerance

Oral Allergy
Syndrome (OAS)

Celiac Disease

Eosinophilic
Esophagitis (EOE)

FPIES

GERD