172 | Alpha-Gal Syndrome: Symptoms, Diagnosis, and Diet

Have you ever had a patient come in with recurrent diarrhea, abdominal pain, or hives? What if the culprit was actually a tick bite? Welcome back to the Exam Room Nutrition Podcast. I'm your host, Colleen Sloan. I'm a PA and dietitian, and today we're talking about Alpha Gow syndrome, a fascinating and often overlooked food allergy that can develop after a tick bite. My guest, Jerry Simons, is a PA with over 25 years of experience treating complex GI disorders and serves as a founding medical advisor to the Tick-Born Disease Resource Center at Stony Brook Southampton Hospital. In this episode, Jerry explains why this allergy can be so difficult to diagnose, including one symptom that might have you rethinking your differential. We also talk about what patients actually need to eliminate from their diets and why. Because as you'll hear, unnecessary food restrictions can do way more harm than good. So whether you work in GI or not, I promise you you will love this conversation because Alpha Gal will come up with a family member, a friend, or someone in your practice. So grab your coffee or drive safe and enjoy my conversation with Jerry. Jerry, I'm so excited to have you on the podcast. I love that we've connected an AAPA, and this is such a cool topic to unpack. So thank you so much for being here.

Great. We need more microbiome and nutrition PAs out there. So I'm a big fan of your work.

Thank you so much. All right, let's jump right in. You're really giving us a masterclass in Alpha Gal syndrome today. So please explain how a tick bite lead to a food allergy.

Yes, right. So when you talk about Alpha Gal syndrome, Alpha Gal syndrome comes from the bite of a tick, specifically a lone star tick, and it's the female lone star ticks that do most of the feeding. Now, Alpha Gal as a syndrome can range from a serious, life-altering anaphylactic reaction where you need epinephrine and ER resuscitation all the way down to a mild, like annoying type of diarrhea. So Alpha Gal syndrome is an allergy from a tick bite. Now, alpha gal itself is a tiny, tiny little carbohydrate. The alpha gal carbohydrate we see in the cells and tissues of non-primate mammals. Humans and apes do not have alpha gal. So, Colleen, guess what? When we get bitten by a lone star tick and it transmits this alpha gal carbohydrate, we see that this as foreign as an invader. So when we eat any of those meats, boom, we're gonna get a reaction to those particular types of meats. When you get that lone star tick bite, that tick, when it's feeding on you, is transferring those alpha gal molecules into your bloodstream. And Colleen, unlike Lyme disease, which could take a day or more to transmit, alpha gal can transmit to you in 10 or 15 minutes because it lives in that salivary gland of the tick. So when you're educating patients, if they get a tick bite, have them remove it immediately, right? So guess what? Now you've got this alpha-gal molecule in your bloodstream, and your immune system's gonna make that IgE antibody against that when you get exposed to these mammalian meats or some kind of trigger.

Yeah, so it's it's so fascinating because it's it's it's different than a lot of the type of syndromes that we see. And so you mentioned a few types of symptoms, but what I find is interesting is there can be a delayed reaction. So can you talk a little bit about that and why it makes it hard to actually get to this diagnosis?

Yes, everybody, if you're a practitioner listening to this and you're taking notes, this is what you want to write down. We are all trained that if you get a bee sting, you react to it. If you eat a peanut, you react to it instantly. But what's interesting about Alpha Gal, because it has to go through metabolism and then be absorbed through the gut, it's a delayed reaction of two to eight hours. Uh, Dr. Erin McGinty, a doctor I've worked with on Long Island, who's an expert in this, she coined the term midnight anaphylaxis. Like you eat a hamburger at a barbecue for dinner, and then at midnight you wake up with hives, diarrhea, even your throat closing, something extreme like that. So everybody, listen to this. If someone comes to you and they're like, I ate a piece of pork and I started feeling itchy right away, I'm like, that's not alpha gal. But if they have a pork chop and six, eight hours later they have hives or loose stools or anaphylactic reaction. That's classic for alpha gal. So that delayed reaction is what can be a diagnostic challenge because patients may not always report or remember, you know, what they ate six or eight hours ago and connect that to feeling itchy all night.

Can someone present with GI symptoms only, or is it is it always like hives anaphylaxis type reaction?

Yeah. So get a load of this important publication we could put the link in in 2022, found that 20% of patients will present with only GI manifestations. This could be a range of the review of systems from simple nausea, vomiting. Most of the time I see cramping and then diarrhea, severe abdominal pain. People, what I want you to look out for is that 30, 40, 50-year-old person, they have never had a GI complaint in their life. And all of a sudden they're presenting to you as a 55-year-old with diarrhea or nausea, a new onset GI, especially in the Northeast, the East Coast, where we see a lot of lone star ticks in the southeast. If you're in that catchment area and you have someone with a new onset GI complaint, think about Alpha Gal.

Yeah, I'm glad you went there because diarrhea is a tough uh complaint to work up, right? It could be so many things. And so uh other than those few things, like recurrent GI symptoms, does that also make you think of Alpha Gal?

Yeah, recurrent GI symptoms, things like the the H2 blockers don't work, the over-the-counter bismuth, yeah, you know, those different types of things don't get a lot of traction. Now, a majority of people will remember some kind of skin reaction, an itchiness or something along those lines later tied in with the GI complaints. Another hint, listen to this. Alpha Gal, the repeated exposure. What does that mean? People that are continually getting tick bites. That continual exposure raises your level of alpha gal. So those landscapers, those hikers, those outdoor people, they're like, oh, I've had ticks on me every weekend all summer. They keep raising the rate. The other hint is this people that are like, oh yeah, a hamburger gives me diarrhea. And now milk products give me diarrhea. Like that could kind of come on during this load up of that. And I know we'll talk more about the diet later.

Yeah, I definitely want to get into that because it's it's just so fascinating. And is the diarrhea with alpha gal, is it bloody or non-bloody? Because I know a lot of other like foodborne illnesses tend to be bloody.

Right, typically non-bloody for that. And again, people may just randomly have diarrhea or they may randomly just feel nauseous. So it's this whole spectrum of GI complaints.

Yeah. Which makes further even complicates it.

Yes. All right.

So we yeah, we'll get into the treatment like with diet and understanding foods that people can and can't eat. But let's say you have a patient you suspect Alpha Gal, how are you diagnosing it?

Right. So everybody, Alpha Gal is that clinical diagnosis. You've got to pin down that story, right? The person that I just talked about ate a hamburger and felt itchy right away. That's not Alpha Gal, right? Um, so you're really getting that story. You're also getting looking at that outdoor activity, that history of tick exposure. Now, if you you've got someone with that, like some of my population are uninsured people. I'm like, okay, we're not gonna pay for blood work, just stick to the diet for three to four weeks, which we'll go over in a minute. But for people with blood work, uh, of course, do a serum IgE. You want to test for the Alpha Gal IgE, particularly. My favorite blood test is from LabCorps. I have the test memorized 65003. What I like about this IgE is it breaks down specifically your allergy to pork, beef, and lamb, as well as doing that total alpha gal count. So make sure you do the IgE, make sure you do the alpha gal panel with those subsets. An interesting thing when you're doing blood work, I like to check people's blood types. It's really good to know that the B type blood, if you have B like boy type blood, that blood is very similar to like an alpha gal molecule. So there is something to it that people with B type blood may not get alpha gal or they have only a very mild reaction to it. Now, a disclaimer, I have some people with B type blood where they have an EpiPen, right? Um, that is so violent. But in general, B type blood can be really protective. And Colleen, even though I haven't gone through a review board, I have my own private research project. And what I've found over about 300 patients is many of them also have low IgA level, immunoglobulin A. Um, and I think that in part contributes to this leaky gut syndrome. My own research, it's not published yet, the lower the IgA, the more violent of a reaction patients will have. And loyal listeners to any nutrition podcast will know that glutamine helps to build up the gut mucosal lining. So we'll get to treatment later, but one of the standard things I do with a low IgA level is I give people glutamine and I track that that IgA level is coming up. Now, the other thing, what are you gonna do? You get all of this blood work back, right? Typically, when you look at that total alpha gal level, the people that are having the highest reactions are usually have a score of two. But I've seen people with scores of 60, 70, 80, like incredibly high, right? Now, most of the scientific literature agrees if you have a very low alpha gal level, like below two, you're gonna have really milder or no symptoms at all. So I always look at that number. Now, one thing that we always try to get out there to all of the clinicians, people, you'll also want to write this down. Don't randomly test for alpha gal unless people are having symptoms, right? I had a college kid who was made miserable because he had a tick bite and Lyme disease. In that panel, they added on an alpha gal, and his alpha gal was 0.26, right? But so I asked him, I'm like, what happens when you eat a hamburger? What happens when you eat jello? What happens if you have a piece of pork? He's like, I mean, I've never reacted to it, but I haven't been able to have it in a year because they said I have a pot I have positive alpha gal, right? But I'm like, if you add lime from a deer tick, that's not really gonna give you alpha gal. So this other office changed his whole diet. He was losing weight, he was unhappy eating fish all the time. I'm like, listen, alpha gal is a clinical diagnosis. If you're not having symptoms, don't even bother testing. And people that do not report a sensitivity, I say, oh, you eat a hamburger and you feel fine. Um, you know, follow your diet, right? Follow your that clinical presentation.

I love that story. I think that's really important and important to share with our patients too, because I'm sure people are seeing things online and there's a lot of misinformation about go and get yourself tested. And and I think that's an important caveat. Now, I didn't hear you say any stool testing. So there is not a stool culture that we need to send out for this, correct?

Correct, right. Sometimes you will see if you do a stool test, like a change in the pH, maybe lactoferin, some of the inflammatory markers may go up, but it's the symptoms and the blood tests that we're primarily looking for.

Is there ever a case where you also have some other things on your differential, like maybe um an IBD or one of the um infectious diarrheas like salmonella or Shigella, where you would do other types of testing? Or is it always like, oh, tick bite, alpha gal, that's all I'm testing for?

Right. So, yeah, like if a patient comes in with a much more dramatic, much more acute GI presentation, where they're like, over the last two or three days I've had nonstop diarrhea with fever and abdominal pain. Um, then we're certainly broadening our differential to look for more um more broadened types of infectious types of agents there. Because this alpha gal is usually indolent and it kind of grows on you. Like, oh, I had a little diarrhea, now I'm having more diarrhea, now I'm having nausea. Yeah, that very rarely, really never have I seen someone with alpha gal where they have abdominal pain, fever, constant watery diarrhea.

Yeah, no, that's that's helpful. All right, so we've gotten to the diagnosis, we're confident with the symptoms, we've gotten the uh testing. So now what? How do we educate our patients? And they're like, okay, great, what can I eat now? Where do you start and what kind of education do you provide?

Yeah, so my protocol is I do what's called a ramp up protocol. The ramp up protocol for me is I tell people anything with hair, anything with a hoof, right? Pork, beef, lamb, right? Those are the things that you need to really strictly, strictly avoid. I also tell people it's gonna take three or four weeks and no new tick bites for you to really start to see a shift. And the advice, Colleen, people don't like this advice. I'm like, for the three or four week ramp up, do not eat at any restaurants because there's so much cross-contamination. In fact, a fun trivia point that I like to give to people one of the most read articles in 2025 in the New York Times was an article in August where they talked about how the most successful restaurants in Martha's vineyard were strictly vegetarian because they were losing so much business because so many people there have alpha gal. So I'm like, listen, do the ramp up diet for three to four weeks. Nothing with a hoof or hair, pork, beef, lamb, no eating out. Now they come back three or four weeks and there's no shift at all. You know, I'm like, okay, we do we have the right diagnosis here? Do we have to look at, you know, a SIBO or any other different types of illness? But if not, this is when um, number one, I check their lifestyle. Um, you know, alcohol, NSAIDs, and exercise make your gut more permeable. So, you know, and making sure that that is not tied in, you know, with any of the different things that they might be eating. In fact, if you have a hamburger with a beer and then you go to the gym, those are some of the strongest alpha gal reactions that are out there. So everybody, we're doing the ramp up. If it's been three or four weeks, then I get into the dairy products. We'll talk more about that in a minute, and all of the gelatin products, you know, the jello pudding and the Knox Nutrijoint, and you know, all of those different um types of things that way. But I do tell people not all hope is lost. Chicken, turkey, duck, shrimp, crab, lobster, um, you could have all of those and think of all of the plants that you love on this podcast, you know, like nuts and seeds, legumes, uh, and those different types of things. Now, all of the data shows that 80% of people feel better avoiding the hoofed meat, and the other 20% really need that uh lactose and gelatin avoidance.

Now, during this ramp up um, I guess elimination diet, are you concerned about micronutrient deficiencies or anything like that? Are you talking about other foods that they can kind of add in or to replace those things?

Right. So most people could do an elimination diet for this first three to four weeks pretty well. But as you know, you know, if in the veget if think of them like a vegetarian, we worry about B12, we worry about iron, we worry about zinc. People remember the college kid that was miserable because he had his diet changed. He was really low on protein. So those are really the big things. And then if you start removing dairy, right, um, we worry about calcium, vitamin D like dog. And another world, another jerry world I'm passionate about is working on vitamin D number two and vitamin D3. Don't forget that you can check both of them in a blood test. Now, vitamin D num D2, you know, that's everybody loves mushrooms, you know, and plants and yeast, but it's that D3 that really comes from animals. So I tell people to up your nice fatty fish.

Great. I I'm so glad you told us that story about that college kid. My heart goes out to him, and I feel like that story, unfortunately, isn't that uncommon when they're prescribed a restricted diet. Sometimes it's unnecessary or sometimes it's prolonged unnecessarily. I think that was an important thing that I want you guys to really remember. Don't just test for this just because you're curious. You know, that could lead to a lot of unnecessary restriction.

Right. Don't like us, don't add it on to your yearly lipid panel, for example. No. And remember that a lot of people with an alpha gal score under two will be okay. Now, guess what? All of your listeners are like, Jerry and Colleen, I have someone with a 0.9 alpha gal. I don't want to go and tell them to eat meat and have diarrhea and all of those things. So, one important thing to remember the alpha gal really is in the fatty part of the meat. So, what I tell people is I'm like, hey, patient, you're in luck because your alpha gal is 0.9. You're gonna ask your husband, your wife, your hot date, your neighbor, somebody to take you out for the finest, most expensive piece of filet mignon, right? Eat that, start with the postage stamp size and see how you react. If you have no reaction to that really low-fat meat, start pushing the envelope. Because the main message you and I want to get out to the world, listen to the patient, don't look at the number on the piece of paper. And I have had dozens of emails where people said, Jerry, your filet mignon trick worked. And sometimes to prove it, I will do another alpha gal blood test, and we see that that number either stays the same or goes down. Now, one important caveat I mentioned briefly, I do give everyone from people with hives and breathing problems to people with mild diarrhea, just my own personal protocol is I do give everyone an EpiPen just in case. Because if they're, you know, doing whatever and there something bad does happen, I have all of my Alpha Gal people have an EpiPen. Most of them never, ever, ever use it, but that's why we're here. We want to guarantee we give patients the best possible coverage.

Great. Thank you. I was gonna ask you that so that you read my mind. Uh, Jerry, you've talked about dairy a few times, and so there's a little bit of confusion there. So, does everyone with Alpha Gal need to eliminate dairy foods? Talk to us a little bit how you handle that.

Yes, yes, exactly. So when you read that 2022 study that's going to be in the comments, we know 80% of people improve with the ramp up level one, just avoiding the meats. But I know you're like, wow, that 20% of people could be a lot, right? Those dairy products with that is driven really by. That alpha gal glycoprotein. It has nothing to do really with lactose itself. Now, every research article is gonna say this. We're still confused on the other side of the exam table because there's a wide variety of tolerances. I have some people, they could have a little bit of yogurt, but if they drink milk, they react to it. Some people, they can't even have a small amount of butter, for example. So during the second phase ramp up, I usually will tell people, you know what? Cut out all dairy for that same time frame, three or four weeks. Okay, now you're at the six or eight week mark, you're on level two, where you're avoiding all of the dairy and you're also avoiding all the gelatins. I'm like, try a little scoop of yogurt or try a little bit of butter and kind of see how you react to that. So as of now in the fall of 2026, the best advice is dairy tolerance is widely variable. Kind of work your patient through it. But I start with total elimination if they get to that level two, and then kind of slowly reintroduce it that way.

And you can possibly reintroduce some of these dairy foods based on tolerance, but do they is this a lifelong avoidance of mammalian meat?

Wow, exactly. So what a great question. There's a lot of interest. Like, can you recover from Alpha Gal, right? Um, I warn people, don't Google too much, right? Because, you know, you'll find that you could only have air and water on some websites. Totally. Yeah. So everybody, you must take time and make sure your patients get no new tick bites. Every time they get another tick bite there uh of a lone star tick, they're reactivating that. So I'm like, if you're avoiding ramp one and ramp two, if you're preventing tick bites, if you're carrying an epi pen, there's your core treatment. And if you are treating someone with alpha gal, when their blood level goes below two, you could try that Filet Mignon trick. Now, on the flip side, I do have three or four patients where they have had only one tick bite. They have an alpha gal level that bumps around between five and ten, still kind of on the low side, and they have a yogurt or they have a jello as a dessert and they react to it, right? So, you know, there are we do have some of these predictive markers. So, in my opinion, with these things, we're seeing people get over alpha gal, but there absolutely are some exceptions.

All right, so we've talked about obvious sources and foods that should be avoided. What are some less obvious exposures? You've mentioned them a couple of times, but I'm sure there are certain things in there that we wouldn't even think about that is really important to discuss with our patients.

Yeah, so a really interesting one. Every podcast needs a good brain twister. This is the podcast brain twist. You've heard of caragetin, which is a seaweed, particularly red seaweed. Did you know that that red seaweed has some alpha gal in it? So I've had people like, I'm a vegetarian. How could I be having a reaction, right? And then you look like they're eating sushi or they're eating like seaweed salads, those different types of things are important. Number two, if you're a cardiothoracic PA and you've accidentally stumbled onto this podcast, this is for you. Because at least on Long Island, most people before major cardiac surgery are getting an alpha gal test. You know where I'm going with this, because in cardiothoracic surgery, they're given a lot of heparin, right? And there have been reports of people that develop either right at the end of the surgery or in the pacu, hives or airway compromise and wheezing and stridor from that heparin exposure. Also, summertime, when everybody loves their marshmallows, right? Marshmallows, we think of gelatin. And everybody, when you're reading that package, everybody listening, when you're reading that package, if it says made with natural ingredients, those natural ingredients, could it be a lard, could it be a tallow, right? You're eating something you think is vegan, but then it says um, you know, made with natural ingredients. Check on that. There is a law going through, I believe it's the House, one of the committees, uh, to actually start labeling foods as alpha gal friendly or not. That may take a long time to come to fruition, but that's you know how important this is. Also, if you look at, you know, if you're a magnesium taker, magnesium stearate sometimes may be made with a gelatin and most squishy vitamins rather than a hard uh tablet or a plastic capsule, many of those squishy uh vitamins may actually be made with gelatin as well.

Okay, I have a couple of questions, but you said a uh 2026 TikTok word of the year, in my opinion. You said tallow. It is like everywhere because everyone's afraid of seed oils, so now everyone's obsessed with consuming beef tallow. And obviously, we need to educate our patients, probably need to avoid, but I'm curious if you've ever seen anyone, you know, now the new thing is like it's a part of skincare and they're applying to their skin. Could they have a reaction with that exposure?

I mean, it certainly could be. Remember the patient who smells food at a barbecue? Yeah. Um, I have had a few patients where they have reacted to products that they've put on their face. So it certainly is possible.

Two other things. Do you talk about collagen supplements or collagen powders and whey protein? Are do those both need to be avoided, or is that kind of uh maybe it depends on each person's tolerance?

Um, I definitely, I mean, in general, I'm not a whey protein person, the gas and the bloating and those different types of things. Um, so yeah, I'll normally like include that in that level two when we start really working on um, you know, uh dairy type products. We know where does collagen come from? Collagen is mostly animal derived, right? Because that's what makes their structures um just like ours, for example. So yeah, like adding, especially as you get to this level two, um, collagen, for example, yes.

Okay. You mentioned heparin. Are there any other medications that we might need to not prescribe for our patients or just be cautious of or avoid?

So we know that the MMR vaccine, right, was an issue with alpha gal patients. And I believe that there's been resolution of that. But I believe that it's mainly any of those soft, squishy. Like if you do like a vitamin D2, like a weekly ergocalciferol, for example. Those are some of the some of the big ones that went. Some of the monoclonal antibodies, you know, that may have animal derivatives, like they came from a mouse, some of those original animal derived. And that's how the the whole world of Alpha Gal got started in 2006 when people were using Rituximab and similar types of agents, and they were getting an infusion and started having Alpha Gal syndrome that way.

What does your follow-up protocol look like? Because you're doing these different ramp-ups, and so I'd love to hear when do you have patients come back to see you? When are you rechecking labs? And then when are you just kind of like, okay, you're good, you don't need to come back and see me.

Yep, exactly. So, number one, very critical that first three to four week period to follow them up and see how they're doing. And then if you do like, if they're like, okay, I'm avoiding all of this stuff, I feel great, right? I'm like, then I would normally give them like six or eight weeks to check their number again and do that same lab core panel that we talked about. For those 20% that don't improve, where we start pushing the gelatin avoidance and we start pushing um, you know, avoiding the milk products, I'll see them in another three or four weeks. Everybody, I'm glad you waited to the end because I gotta tell you, if you're on the second ramp up level, if you're six or eight weeks into this journey and the patient is not improving, either A, they're secretly not following the diet, B, they're getting new tick bites, or C, you're going down the wrong path, right? I had someone whose alpha gal was like 18 and things weren't changing, and you know, they ended up having mast cell activation syndrome from a whole nother world. I'm like, lady, you got mast cell. This is an alpha gal, right? So, people, if the diet, if the glutamine is not working and you're a couple months into it, change your perspective.

Yeah, that's a great piece of advice. I completely agree with you, Jerry. This has been so fascinating. I feel like Alpha Gal is one of those syndromes that you would absolutely kill it if you went to like a trivia and they asked all these trivia questions because it's it's so unique, it's so interesting. And so thank you for sharing wisdom. I learned so much from you. This was an incredible masterclass. If people want to connect with you, because I know you speak nationally on a bunch of different GI topics, you know, you're on social media, so where can they connect with you online?

Yeah, they could find me. I'm on Instagram, I'm on LinkedIn, um, where you can find, and I'll put some of my contact info in the show notes as well.

If there is someone who's interested in becoming an Alpha Gal expert like yourself, what types of training is there? Is there an organization that they can join or anything like that so that they can learn more to be able to treat patients appropriately?

Right. So I'm part of the Stony Brook Southampton Tick-Borne Disease Resource Center. So we are in the epicenter of Alpha Gal. So most of my knowledge came from on-the-job training and working with uh this Dr. Erin McGinty, who is one of the leading allergists that are out there. The different allergy societies do have really good information there. The other group that I work with, the Global Lyme Alliance, has some great info on Alpha Gal. The International Lyme and Associated Disease Society has some great Alpha Gal info out there as well. But look to those allergy associations.

Perfect. I will link down to all of those resources, the research paper he mentioned, and his social media links as well. Definitely get connected with Jerry. He's obviously a wealth of information. Jerry, thank you so much for the gift of your time. I've loved chatting with you today.

Fantastic. It was great. See you next time.

And thank you guys for carving out some time for nutrition. I'll see you next week.