Why do some people who were previously able to eat certain foods without issue suddenly develop a food allergy or sensitivity? One possible answer is Alpha-gal syndrome.
Alpha gal syndrome is becoming increasingly prevalent nationwide, no longer confined to the East Coast of the United States. It arises after a tick bite, which might go unnoticed, and its symptoms can easily be mistaken for other common conditions like food allergy, environmental allergy, irritable bowel syndrome, SIBO, histamine intolerance, and other digestive complaints such as nausea, pain, and diarrhea.
Let’s explore alpha-gal symptoms, causes, diagnosis, and treatment in more detail.
What is Alpha-gal?
Alpha gal is a compound found naturally in mammalian meat, including beef, pork, lamb and deer. People do not normally react to the alpha-gal compound found in meat, but the bite of a tick can change things.
The tick’s saliva contains the same alpha-gal molecule as meat. When a tick bites a person, the alpha-gal molecule in the saliva enters the person’s body. Now, the person’s immune system goes to work to protect the person from the alpha-gal molecule, which is seen as a “foreign invader.” From that moment forward, the person reacts to the alpha-gal protein.
Because it is the same compound as in meat, a person can no longer tolerate beef, pork, lamb, venison, and other red meats because the body sees them as “foreign,” like a virus. The body starts an immune reaction to try to protect the person from the alpha-gal in the meat.
The body can’t tell the difference between the alpha-gal in the meat vs. that from the tick.
In addition to symptoms after eating meat, reactions may also occur when using products containing animal-derived ingredients, such as cosmetics, or consuming medications or supplements that have capsules made of gelatin. In this case, the blame is often ( and incorrectly) placed on one of the other ingredients in the product.
Alpha gal is short for galactose-alpha-1,3-galactose.
Alpha gal Symptoms
Symptoms typically occur 3-6 hours after eating meat and range from mild to life-threatening. *
Alpha-gal syndrome is the reaction that occurs after a person is sensitized to the alpha-gal compound. Symptoms of alpha-gal syndrome can emerge at any age, even in individuals with no previous health issues, making it challenging to link them to meat or meat ingredients. Additionally, since AGS develops after a tick bite, symptoms might be wrongly attributed to tick-borne diseases like Lyme disease. Some individuals test positive for alpha-gal sensitization but experience no symptoms, a phenomenon not fully understood yet.
These symptoms can vary, ranging from isolated digestive issues to a combination of different symptoms. It’s not unusual to experience digestive symptoms without any accompanying signs.
- Stomach pain
- Rash
- Itching
- Hives
- Nausea
- Vomiting
- Diarrhea
- Difficulty breathing
- Headaches
- Runny nose
- Severe anaphylaxis
*Symptoms can occur immediately, but this is less common.
Alpha gal exposure has been reported as a significant risk factor for heart disease even in those not experiencing symptoms when eating meat.
It Can Mimic IBS
AGS causes digestive problems and people can be mistakenly diagnosed with irritable bowel syndrome (IBS)
A 2021 study in the journal Gastroenterology looked at whether or not people with AGS could have ONLY digestive symptoms. The answer was yes! In this study, three-quarters of the patients had resolution of their “IBS” symptoms with the removal of meat and meat products. If this is the case, before the diagnosis of IBS is given, all patients should have a thorough history taken, which includes questions about tick bites. And, testing for alpha-gal IGE should be considered.
Dra. Amy Burkhart
It Can Look Similar To Histamine Intolerance & MCAS
AGS can also look like histamine intolerance and MCAS. AGS testing should be considered in these populations
Rashes are common in alpha gal syndrome and can be mistaken for histamine-related issues or mast cell disorders such as MCAS. Because the treatments for each condition are different, testing for alpha gal should be done in people with histamine intolerance and/or MCAS.
Dra. Amy Burkhart
Dra. Amy Burkhart
How Common Is It?
The number of cases has risen from 12 in 2009 to 34,000 in 2019.
In the United States, alpha-gal syndrome is primarily found in the southeastern states, where ticks carrying the alpha-gal allergy are prevalent. It’s estimated that around 15-30% of individuals in these endemic areas have antibodies to alpha-gal. Nationally, approximately 3% of the US population tests positive for alpha-gal antibodies, equating to nearly 10 million people.
While Australia has the highest reported cases globally, alpha-gal syndrome is also present in regions across Asia, Africa, and Europe. However, the specific tick species responsible for transmitting the syndrome varies in these countries.
Why is alpha-gal on the rise? Could it be increased awareness? The number of people on the planet? Or could it be the earth’s way of telling us to focus on climate change? With increasing temperatures, the tick population is rapidly increasing and the number of cases of alpha-gal syndrome rising. Cattle raising produces large amounts of greenhouse gases. Is this nature’s way of controlling how much red meat is produced and consumed on the planet? A little food for thought.
Diagnosis Of Alpha-Gal Syndrome
Alpha gal syndrome is diagnosed by blood tests and a history of a tick bite correlating with the onset of symptoms.
The following criteria are currently used for diagnosis:
- Reactions occur after eating mammalian meat without problems for many years, onset can be at any time.
- Reactions range from mild to severe and vary person to person
- Reactions start 3-8 hours after eating non-primate mammalian meat. Reactions may also occur after consumption of dairy, gelatin, or other mammalian-derived products containing alpha-gal for some patients.
- Positive testing for alpha-gal IgE (>0.1 IU/mL)
- Improvement of symptoms when adhering to an appropriate avoidance diet
It is important to note; there is not yet a defined criterion for what blood levels equate with the diagnosis. In addition, not everyone who tests positive has symptoms (7).
Which Ticks Are To Blame?
The lone star tick and the black-legged tick are responsible for most cases in the U.S.
In the United States, these are most common in the Southeast, but the tick population is growing. This is attributed to climate change and an increase in the deer population. In Europe, the castor bean tick is the culprit, and in Australia, the blame is placed on the paralysis tick or Ixodes tick (1).
Lyme Disease & Other Tick Born Diseases
Because the symptoms of AGS occur after a tick bite, confusion with Lyme disease symptoms occurs.
Lyme disease diagnosis can be difficult, and laboratory evaluation is not perfect. Because of this, some people are diagnosed with Lyme disease based on the history of a tick bite and new symptoms. You see the problem.
If a person is mistakenly diagnosed with Lyme disease, and the reason for their new symptoms is AGS, the treatment is drastically different from the treatment for Lyme disease. Lyme disease requires antibiotic treatment. If the problem is AGS, the treatment is dietary avoidance and may only be temporarily needed. Antibiotics are not required in AGS, and their long-term use can cause adverse effects on the microbiome and immune system.
Consider AGS, Lyme, and other tick-borne diseases if new-onset symptoms occur after a tick bite.
Treatment
An epi-pen should be prescribed to anyone diagnosed with AGS.
Treatment involves educating the patient on avoiding meat and products containing ingredients derived from mammals. This includes medications and supplements which are commonly made in gelatin-derived capsules.
Avoiding products that contain alpha-gal is essential. Unlike most allergies, the reaction to alpha-gal tends to decrease with time. However, if additional tick bites occur, the immune response can increase and become more severe (2, 3).
All people with alpha-gal allergy should be followed by an allergist and be checked routinely for blood levels and ongoing symptoms.
Factors such as alcohol, exercise, menstruation, and NSAIDS can worsen the reaction. Cooking does not destroy the alpha-gal molecule in meat. Collagen and gelatin must be avoided.
Foods To Avoid With An Alpha Gal Allergy
All products from mammals must be avoided
A person’s response needs to be determined by working with an allergist. This is especially important if the reactions are severe.
In the meantime, it is essential to avoid any food, medication, supplement, or health and beauty product derived from meat.
Some people are able to tolerate small amounts of products containing alpha-gal but the level should be determined in conjunction with a doctor. Trying small amounts without guidance may prove dangerous.
Foods to avoid:
- Beef
- Pork
- Venison
- Lamb
- Milk – only avoid if it causes a reaction (4)
- Rabbit
- Goat
- Bison (Buffalo)
- Lard – common in pastries and some Latin food
- Gelatin ( Jello, Marshmallows, jelly beans, candy, capsules for vitamins and medications)
- Collagen
A more complete list of foods containing alpha-gal is provided at this link by the alpha-gal organization.
Because gelatin is used in many foods and supplements, great care must be taken to prevent accidental ingestion of gelatin, and all labels checked before eating or use. Packaged food products, such as soups, stews, gravies, and frozen meals, can potentially have red meat or a hidden red meat by-product, such as gelatin or tallow. Care must also be taken with cosmetics and other health and beauty products to ensure that they do not contain any gelatin or animal products.
Foods That Are Safe For A Person With Alpha Gal Allergy
- Fish and poultry products are safe
- Fruits,
- Vegetables,
- Beans/legumes
- Grains
- Herbs and spices
Medications To Avoid If You Have Alpha-Gal Syndrome
Medications may contain gelatin or other animal by-products. It is important to discuss safe medicines with the pharmacist.
The following medications are NOT recommended for anyone with alpha-gal syndrome.
- Heparin
- Cetuximab
- Vaccines that contain gelatin
- Any supplement in a gel capsule-these are common
- Any supplement or medication with magnesium stearate, including Tylenol, naproxen, lisinopril, clonidine, and Vicodin. Ask the pharmacist for an ingredient list of any medication you must take.
Alpha Gal And Alcohol
Most alcoholic drinks do not contain animal byproducts and are approved to enjoy, even with a diagnosis of AGS. However, drinking alcohol simultaneously with accidental ingestion of a mammalian product can lead to a faster, more severe reaction.
Prevention Of Alpha Gal Syndrome
To date, the only known way to prevent alpha-gal syndrome is to prevent tick bites.
- Wearing full-coverage clothing
- Use tick repellent
- Check for ticks as soon as you return indoors
- Remove the tick immediately if found
You are at increased risk of acquiring alpha-gal syndrome if you have mast cell abnormalities such as systemic mastocytosis (9).
Dra. Amy Burkhart
Where To Find Help
Seek out help from your primary care doctor or an allergist. A patient support network can be found at Alpha-gal Information,, a non-profit aimed at providing education on AGS.
Alpha-Gal Recap
- Alpha gal syndrome is an allergic reaction to a compound found naturally in mammalian animal products and anything made with those foods.
- The condition is triggered after the bite of particular ticks.
- In the US, it is most common in the southeastern states.
- Over time, the reaction’s severity may decrease, but until that happens, it is vital to avoid all food, supplements, and cosmetics containing alpha-gal.
- An epi-pen should be carried at all times.
Recent Research
- Tick Saliva and the Alpha-Gal Syndrome: Finding A Needle In A Haystack
- Alpha-gal syndrome masquerades as IBS
- Successful beef desensitization in 2 adult patients with a delayed-type reaction to red meat
- Diagnosis and management of patients with the α-Gal syndrome
- Discovery of Alpha-Gal-Containing Antigens in North American Tick Species Believed to Induce Red Meat Allergy
- Diagnosis & management of alpha-gal syndrome:lessons from 2,500 patients
