- Natural Endocrine Solutions - https://www.naturalendocrinesolutions.com -

Overcoming Mast Cell Activation Syndrome and Histamine Intolerance with Beth O’Hara

Recently I interviewed Beth O-Hara, as she discussed how to 0vercome mast cell activation syndrome and histamine intolerance. If you would prefer to listen the interview you can access it by Clicking Here [1].

Dr. Eric Osansky:

With me, I have Beth O’Hara, who is a functional naturopath and functional genetic analyst. She has a doctorate in naturopathy specializing in functional naturopathic approaches and a Masters in marriage and family therapy. She has over 10 years of experience working with hundreds of clients with mast cell activation syndrome (MCAS), mold toxicity, and related conditions. She has been through this journey herself, going from bedridden in excruciating pain and unable to function to living a full and joyful life by addressing the underlying root causes. Her mission today is to empower those struggling with sensitivities and significant chronic illnesses to reclaim their own full potential through individualized, precision approaches. Thank you for joining us, Beth.

Beth O’Hara:                          

It’s great to be here. I’m so excited. I think a lot of people in the community you have will find some light bulbs going off in this conversation. There is a big link to what we’re talking about and thyroid issues.

Dr. Eric:

I agree. I’m excited as well. As I said in your bio, you had a significant health journey yourself. That’s what got you into this field. Can you share some of that journey with us?


Sure. I find that it’s a journey that a lot of people in the chronically ill population can relate to. I’d like to start there because it gives people hope. I started developing health issues when I was a child. I was about eight or nine when I started having some strange symptoms. We had moved to the country into an old farmhouse. I’m in my 40s now, so this was a few decades ago. Nobody knew anything about mold or Lyme back then. It’s not even talked about enough now, but back then, it really wasn’t on the radar.

Looking back, the farmhouse had quite a bit of mold, so I developed mold toxicity at a young age. We were in the country. We played outside. We were bitten by ticks. I thought we were having a Laura Ingalls Wilder kind of adventure. I didn’t have the stamina that my friends had. I couldn’t keep up in sports. I didn’t have coordination. Then I was kicked in the head by a horse when I was nine and had a traumatic brain injury. I had severe anxiety. I was then in a car accident when I was 16 and had severe fatigue. I just couldn’t seem to come back from that. I would whip myself every morning just to get out of bed to get to school on time. I did keep moving forward.

I was very driven to go to medical school, and that was the only thing I wanted to do. I had no backup plan. To illustrate how important this was for me, for my birthday, all I wanted was copies of Grey’s Anatomy. That was all I cared about. I was the weird little kid going through the woods finding bleached piles of bones and trying to put the skeleton back together. This was my super interest and my passion.

I went to college. I developed fatigue and brain fog, and the anxiety was severe. My junior year of college, I moved into a duplex that was 150 years old. It smelled musty in the basement. I didn’t know about mold again. My health really crashed. I worked my rear off and had multiple scholarship offers to medical school, and I had to turn them all down.

Instead of getting to go pursue my dreams, I became this chronically ill person. By the time I graduated, I barely finished my Bachelors. I went from this high-performing person, working three jobs, teaching at a vocational school, doing independent study research, taking graduate school classes, to taking the minimal number of credits to graduate. Nobody could figure out what was wrong with me. I had joint pain. I had brain fog. I had severe fatigue. I had blood sugar crashes to where I had to eat every two hours. Just to go out of the house, I had to bring a snack. This continued to accelerate so by the time I was in my later 20s, I had to walk with a cane. I wasn’t really even walking; I was barely hobbling. The joint pain was like walking with ground glass stuck inside my knees and my toes and my fingers.

I was misdiagnosed with rheumatoid arthritis. Treatments didn’t help because it wasn’t the right diagnosis. If nothing else, I was persistent in trying to find help. I exhausted traditional medicine, holistic. I did homeopathy, shamanic work. I did anything I could do. I did therapy to clear any kind of emotional pieces. I was the most complex case that all the practitioners I’d seen had ever worked with. They would tell me, “I have never met anybody as complex as you.”

I became extremely sensitive. I couldn’t tolerate any medications or supplements. I was having paradoxical reactions to everything I tried. Practitioners started telling me I was crazy, that it was in my head. I wanted to be sick, and I was getting something out of being sick, which was the farthest from the truth. I share that part because that’s also a common story. I hear it every week in my clinic. I’m sure you hear that all the time.

Fast forward. I had seen about 75 practitioners. I just kept spiraling downward until I hit a whole year of being bedridden. I could barely function. It was a good day if I could get the dishwasher unloaded, and then I couldn’t get it loaded. It was too much.

But I did land on first histamine intolerance. I had itching head to toe. I had all kinds of GI issues. Sleep disturbances. I didn’t sleep for four years. Practitioners would tell me, “You can’t go more than two weeks without sleep.” Not true.

Then I learned about this thing called mast cell activation syndrome. This was when it was still in the theoretical phases. This is fairly new on the scene of traditional medicine. There have been studies and theories about this for a few decades. Case studies coming around 2000, theorized around late 1980s/early 1990s. When I saw the descriptions, I said, “Oh my gosh,” everything makes sense. My GI symptoms, my skin symptoms, brain fog, fatigue, anxiety. This horrific insomnia. All of this is connected. The bladder pain, everything I was dealing with. I had symptoms in every system. I was pretty severe.

Learning about that started shifting my mindset of what we were looking at. I realized we weren’t chasing all of these separate things. This is all connected. The next question was why? Why are these mast cells dysregulated? We knew I had Lyme and bartonella and babesia, but I couldn’t treat it. Then we realized I had mold toxicity. That brought this huge lightbulb to what was going on, why I had the nervous system dysregulation, why I was so sensitive. That allowed me to start to unravel what was happening. I unfortunately had this premed back then. Every moment in my brain would work, I was studying, I was pulling things out, I was chasing down anything that could help. I started putting pieces together.

Eventually, I did get my brain back. I got my life back. I can wear heels, which doesn’t sound like a big deal to most people but is super exciting to me. I was somebody who at 28 had to walk in orthopedic shoes. I don’t wear stilettos, but I can wear cute shoes. I can go hiking. I don’t have stamina like an athlete does, but I can exercise for an hour. That’s a huge thing for me.

I went back to graduate school. I got two graduate degrees. I started this busy practice. I work a little too much and am working on that. But I can do it. I feel vibrant. I don’t feel like the person from 15 years ago. Even telling the story, I feel like I’m talking about this other life. It’s not the life that I relate to today. I do have a lot of health maintenance. I’m not out there eating Pizza Hut and McDonald’s. I eat very clean. I take my supplements. I exercise. I do my castor oil packs. I do my sauna. I do all the things to take good care of me.

But you can recover. I was one of those cases that practitioners didn’t think I would come back from. I was told I would be in a wheelchair by the time I was in my 30s. I could expect to have really poor quality of life. That road I was going down, that’s what was to be expected. Fortunately, we know all kinds of things we didn’t know 15-20 years ago. I see very similar cases: People recover within 3-4 years. They don’t take the 15-20 years that it took me or the hundreds of thousands of dollars it took me. That is the light at the end of the tunnel that I want to share.

Dr. Eric:

Thank you so much for sharing that story. You have been through a lot, but it’s great you’re doing so much better. Like you said, you need to maintain your health. You can’t go out and eat anything, and I’m sure stress management is important. Diet and lifestyle is huge with any chronic health condition.

One thing I want to ask: Most listening to this have a thyroid or autoimmune thyroid condition. There are certain symptoms associated with hyperthyroidism and hypothyroidism, some of them more classic, some of them not as common. With MCAS, are there classic symptoms associated with it, or does it really vary depending on the person?


Great question. Maybe we should start because this may be brand new for some people: What are mast cells? I like to think of these as our front-line defending and sensing cells of the immune system. They’re in almost every tissue in the body. The only tissue I have ever seen documented that is up to date is the retina doesn’t have mast cells. I used to think the brain didn’t have mast cells, but that has been disproven in the last few years. We even have mast cells inside the brain. They’re sensing every molecule of air, food, water, supplement, medication, anything you put in your mouth, anything that we smell, that we touch. They’re sensing stressors. It’s that role of chronic stress.

They’re also sensing what’s happening inside our bodies. They line the blood vessels. They’re sensing the blood going through the vessels. They have hormone receptors for things like estrogen, progesterone, and thyroid hormones. The thyroid tissue has mast cells. They have over 200 different types of receptors. Some of the most complex cells in the body. They’re also sensing for pathogens, viruses, bacteria, parasites, molds, yeasts. There are all kinds of censors for different types of medications, even Vitamin D, which is actually a hormone.

And neurotransmitters. They have receptors for many different types of neurotransmitters and neuropeptides. They have over 1,000 different mediators housed inside of them that they can release. Most people are familiar with histamine. They are one of the major cells that release histamine. A couple others in the body. Prostaglandins, cytokines, now a household name. We could go down the list. Cell signalers.

What they do is mobilize an immune response if it’s needed. For example, if you cut your finger, you don’t get the bacteria cleaned out, and it starts to get red and puffy. That is the mast cells creating local inflammation as a protective mechanism. If we get a surgery, we get some local inflammation around the surgical site. Part of that is mast cells protecting us. If we get sick, and we get sinus congestion and the sore throat, that is not the virus itself, that is our immune system launching a protective attack.

They should be doing this normal protective response and then restabilizing. They are releasing these inflammatory mediators to protect us and then restabilizing themselves. In MCAS, the mast cells have become dysregulated for a variety of reasons, but really, it boils down to an overload of pathogens, toxins, stressors. Stressors could be emotional trauma, injuries, surgeries, and so on. Any combo of those.

Instead of being security guards, or guards of the castle gate, they are on an eight-hour shift, they do their work, they protect you, but they get to take a break and recharge. Just like as human beings, if we work security duty, we would need to take a break and recharge. But we live in a world now that is an onslaught of chemicals, EMFs, mold. All this stuff coming at us. So much that we didn’t have 150 years ago, 1,500 years ago, 15,000 years ago. Our mast cells haven’t caught up to this rapid change in the world that we live in. Even the level of stress that we have, just getting the kids to all the extracurriculars and getting through traffic and trying to pay the bills and coming out of this pandemic. All the stuff we deal with day in and day out. The war in Ukraine. The amount of stress that we’re all under day to day is astronomical compared to what we used to have.

Now the mast cells, instead of getting to do their protective job and relax, are all on guard 24/7. Just like if we were on guard 24/7, we would lose our ability to think clearly and start to lose our fine tuning. Instead of just firing at pathogens and toxins, now they are firing at what I think of as butterflies. We can start to have increased inflammation for all kinds of reasons, things we may not even think of as being triggering. Some people get food triggers. Not all but some. Some people get triggered by perfume somebody is wearing in the grocery store. They get triggered by the fragrance in laundry detergent, by molds, and so on.

These mast cells can become hypersensitive and overresponsive. The important information about this is MCAS is now affecting 9-17% of the general population.

Dr. Eric:



It’s huge. That’s at least one in nine. We’re talking closer to one in seven people dealing with this. People have no idea. It’s one of the most under-recognized, under-addressed conditions.

How do you know if you have this? There is going to be inflammatory symptoms in two or more systems: skin, GI tract, thyroid, bladder, reproductive organs, muscles, bones, nervous system, brain. Anything like this. That’s what makes figuring out who has this tricky. You need to have other things ruled out. Make sure there is not a cancer, IBS, those types of things. But those are all linked to mast cells. If there is inflammation, there is some mast cell involvement.

Symptoms can vary greatly. To circle back to that first question, symptoms can really vary because it depends on which mast cells are activated, in what tissues, which of these thousand mediators are being over-released, and which receptors are overly sensitive. If we think about the number of possible combinations there, it’s almost impossible to calculate.

Some classic examples are people who have skin symptoms, like hives, rashes, flushing, allergy symptoms. We’re not talking seasonal allergies. That is there for a short term, with pollen, and then it’s gone. This is going to be year-round. It may wax and wane, but it’s not like you have it in the spring and fall, and then you’re fine. And it has to be multiple systems. Some people get anaphylaxis reactions or anaphylactoid reactions. Those are the really frightening, “My throat is closing. My chest is tightening. I feel like I’m going to pass out. I do pass out. Blood pressure drops.” You don’t have to have those to have MCAS. Not everybody gets skin symptoms, so that’s some misinformation out there. If you don’t have hives, you don’t have MCAS. That’s not true.

Some other presentations can be GI issues: acid reflux, constipation, diarrhea, abdominal pain, the visceral hypersensitivity kind of pain. It can be lung issues with congestion, asthma, chest tightening. We can have sinus-related symptoms: post-nasal drip; red, inflamed, itchy eyes. We can have issues with urinary burning and pain. For women, we can have menstrual difficulties. Muscle pain, joint pain, fibromyalgia-type pain. Hypermobility is really linked. Orthostatic, tachycardia syndrome. Blood pressure changes are rapid with sitting and standing.

Because there are so many symptoms, we could spend the whole time doing just symptoms. I did put together a symptom survey people can find for free on our website, MastCell360.com. Under MCAS, there is the Symptom Survey. That’s based on the symptoms clearly correlated in the research. The more symptoms you have, the more likely you have MCAS. You can just count them.

Every form of autoimmunity that has been studied in relationship to MCAS has been linked to the mast cells. That will include Hashimoto’s, Graves’, rheumatoid, autoimmune GI symptoms, eczema, psoriasis, all these things. The reason is mast cells sit at this interface of the immune system. They have a role in fighting off pathogens. When our pathogen-killing side gets overwhelmed, this chronic inflammation side comes up, and those work like a seesaw. We have this elevated TH-2 for a long time. Certain positions can open us up toward autoimmunity, branching off that TH-17 response.  You may not develop autoimmunity. As far as I know, I have not had autoimmunity fortunately. But there is a huge number of people with MCAS that do have autoimmunity. If you have autoimmunity, that is a dead ringer. Go check for MCAS.

I know that was a long answer. Hopefully that hit at what you were asking.

Dr. Eric:

You gave a lot of great information and answered some of the questions I had for you. With the prevalence, you said 9-17%?


That’s what the population studies have shown.

Dr. Eric:

I assume it’s increasing just because of the factors you mentioned earlier, like the increased toxic burden, the mold.


We do think it’s on the rise. Just looking at case presentations from decades ago, beyond the increased understanding. When I talk to people who have been in practice for 40-50 years, Dr. Neil Nathan is a mentor and friend of mine who has been in practice for 40 years. He talks about noticing that the cases have gotten more complex, more challenging. Have you noticed that in your practice?

Dr. Eric:

I have. I have been doing this now for about 12 years. I would say that I think with any practitioner, the more experience they get, the more complex patients they see as well because of that experience. I think it’s a combination, but I agree. I would definitely say over the years I’m seeing more complex patients compared to 10-12 years ago.


What I am finding is what worked 10 years ago isn’t working today. We know that something is shifting. Someone came in with candida issues, and I could work with them on herbals 10 years ago. They would be cleared up in 3-6 months. Boom, they were happy. That was easy. It’s not knocking it out now. Even these organisms are changing with what’s happening in our environment.

Fortunately, we have the knowledge to address it. We need more practitioners working in this space. We have some trouble that we’re in around what’s happened environmentally.

Dr. Eric:

When it comes to multiple chemical sensitivities, is MCAS linked to that as well? Or is it a potential cause?


There was a great study that came out- Tania Dempsey was a co-author on that study. They called it TILT; I’m forgetting the acronym. That study definitively showed a role of mast cells in chemical intolerances, which makes a lot of sense because these mast cells are sensing everything that’s happening chemical-wise, whether we’re getting it through skin products that have parabens or a Glade plug-in, and releasing inflammation. They line every nerve ending and the nerve sheaths.

Mast cells are interwoven with the nervous system. That is why I said it was really important that mast cells have receptors for neurotransmitters. They can also release certain neurotransmitters. The nerve endings have receptors for some of these mast cell mediators. There is this constant cross-talk. That’s why when we start to get into MCAS, if we have a flare, they are getting triggered and activated, we can get all these nervous system symptoms, like heart palpitations or throat closings being triggered from the nervous system signaling. That’s why we can get reactions within fractions of seconds.

When people say, “As soon as my husband starts grilling,” someone for whom that’s a trigger may literally start to have reactions before they register the smell because the limbic system has already registered it. There are mast cells in the limbic system. It’s sending a danger signal through the body. This is often when people are told they are crazy because they used to think that immune cells could react that rapidly, but it’s through that nervous system signaling that it’s happening.

Dr. Eric:

You mentioned an overlap between MCAS and different autoimmune conditions. Not everyone with MCAS develops autoimmunity, like you said. As far as you know, you don’t have an autoimmune condition. Just so I can better understand, some of the same triggers of MCAS could also affect autoimmunity, such as food, stress, chemicals, infections, the shift in the immune system, the TH-2 dominant condition.


It is. We looked at all these chronic conditions, like autoimmunity, MCAS, cancers, bowel disorders, neurodegenerative diseases. We keep trickling them down to the same root causes: pathogens; toxins, including mold; chemical toxins; metals; and stressors. We underestimate the role of chronic stress, but it’s huge.

The model I found that describes it the most is the cell danger response (CDR) model developed by Robert Naviaux, who looks at when we have an overload of these events, then the body is going to go into protective survival mode. The expression of that is going to look different person to person depending on their unique biology. For some people, it’s MCAS with autoimmunity. For some people, it will be neurodegeneration or cancer. We can pull it all back to the similar to problem. How is it going to be expressed?

In terms of these triggers, for example, food, certain smells, they are variable from person to person. Some people have histamine intolerance. Lectins are big in autoimmunity. Oxalates are a big deal in the thyroid. They enlarge the thyroid and can disrupt the thyroid functioning. A lot of times, it’s where the biochemistry is getting disrupted by something underneath. We peel back to why. If we can address that why, many times, the expression and sensitivities will improve.

I used to be so incredibly sensitive. If someone is on an elevator, I couldn’t go in because I couldn’t take the risk that they were wearing any type of fragrance. I don’t want to risk passing out in the elevator with a stranger. I couldn’t take an Uber or a taxi because they would have those fragrance things. When I couldn’t walk, that was oxalates, I realized over time. I can tolerate a much wider variety of oxalates now. I don’t eat beets, sweet potatoes, almonds, chard, or spinach now, but I can eat all kinds of foods that I couldn’t eat before with a dressing. The mold toxicity, the Lyme layers, the load is off of my body. We see that a lot in autoimmunity as well. People may have to be careful with lectins long-term because those are different in terms of activating. There are leptin receptors on mast cells, so it’s part of that link.

Dr. Eric:

I also read a journal article that said mast cells can potentially decrease regulatory T cells, which keep autoimmunity in check. That is another potential mechanism to make someone susceptible to an autoimmune condition.


It’s through this cytokine network. There are inflammatory and anti-inflammatory cytokines. That level is beyond what I understand right now. Serious immunologist level. They’re communicating to the B cells, T cells, and every kind of immune cell there is. I think of mast cells as being one of the big conductors and orchestrators of the immune system, keeping everyone in check. They are not the only cells doing that, but they have a big role to play. If your conductor gets out of sync, the whole orchestra will be out of sync and start to get dysregulated, too.

Dr. Eric:

Are there any other links you know of between thyroid health and MCAS?


One of the biggest ones is mold toxins. This was a game changer in my practice in terms of really jettisoning the successes we got. We realized how common this is. Many people are underestimating the impact of mold on their chronic illness. Either they get a urine test, which shows low levels. They don’t realize those are fat soluble, so everyone has low levels on the first test. Or they only get one test, so it looks negative, so they don’t go any further.

Mold toxins have a huge effect on the thyroid. I do more frequently see hypothyroid. The thyroid needs iodine. In the mild toxicity population, I see iodine supplementation, until that mold layer is addressed, can tip people into hypothyroid. I did that to myself. I know I mentioned before I had hypothyroid. I was trying to get a little bit of iodine in. I am not old enough to have perimenopause; I think I’m not ready yet. I started having these heat flushes, and I was sweating. I didn’t used to sweat. All of a sudden, I am sweating in December. I run cold all the time, and I like it to be 78 degrees. I am hitting it down to 70, and my husband is cold. He is the Canadian, so he is usually hot.

We do have to be careful with that. I don’t know the exact mechanism of why, but I find people are more sensitive to iodine. It has a real disrupting effect on the thyroid function itself, on the thyroid hormones. We often will see that hypothyroid state. It usually gets better. I’m sure you find gluten being a big role with those proteins being so similar to thyroid. Getting the mold toxins out. If people can’t get those Hashimoto’s antibodies in check, they will get those mold toxins addressed, and they will usually drop down pretty well if other triggers are handled. Not if someone is eating gluten.

Dr. Eric:

A lot of people who have mold also have Lyme. If someone has mold and Lyme or coinfections like bartonella, would you prioritize the mold? The first problem is trying to get rid of the source of the mold.


That is often a game changer for people who have had cases like mine and can’t tolerate Lyme treatment. Or people who have had Lyme for years and years and still have symptoms. There is often this missing mold layer. If someone has acute Lyme, they were just bitten by a tick last month, they have the fevers, and they are trying to fight off the infection, that’s a different story. People who have had chronic Lyme for years, like I did, if there is that mold layer, I find it’s much better to peel back the mold layer first for a few reasons.

Lyme and mold have very similar symptoms. When I say Lyme, I mean that to mean tick-borne infections. Particularly bartonella can look like Lyme. Not everyone gets this, but lightning bolt pains, or these shooting pains that move around. Tinnitus is really common. One of the most challenging symptoms. If you clear the mold layer, about 30-40% of cases, at least that I see, can spontaneously clear the Lyme. The body’s immune system kicks in.

That happened for me. As I worked on these other layers, my Lyme symptoms went away. They’re nonexistent. I never tolerated the antibiotics or stronger herbals. But about 60-70% have to address the Lyme or tick-borne infection layer. They tolerate the treatment so much better because you have gotten this massive toxin load out. As you are killing these pathogens off, the body is not trying to clear all these mold toxins with the biotoxins. The immune system is in better balance since mold toxins are huge immune deregulators.

We don’t give mold toxins the kind of credit they deserve in terms of how toxic they are. To put it in context for the listeners, they use these mold toxins for chemical warfare. Mycophenolic acid is used as a chemotherapy drug, and it’s one of the most toxic. They are highly carcinogenic. They disrupt every system of the body. It’s extremely estrogenic. It’s numerous times more powerful than human estrogen. Lots of reproductive cancers and other issues associated with that, like endometriosis and PCOS. We need to take this seriously. Neurodegenerative issues, Parkinson’s, Alzheimer’s, are linked to it. Big deal.

Dr. Eric:

You mentioned histamine is just one of many mediators released by mast cells. Can you talk more about the relationship between MCAS and histamine intolerance? How someone could know if they just have histamine intolerance versus MCAS.


The symptoms can be similar. Histamine intolerance, we’re just talking about histamine. We’re not talking about tryptase or any other mediators. Histamine intolerance happens when the histamine in our bodies exceeds the capacity of the enzymes that break it down to remove it. The major enzymes we talk about are DAO, HNMT, which is dependent on methylation. Some of our more savvy listeners probably found that out. There are these other enzymes rarely talked about that are related to it: ALDH, which also breaks down alcohol. People with histamine intolerance often have trouble with alcohol as well. That pathway is affected. Acetylation, there is liver pathways. There is a glucuronidation pathway involved, and so on.

DAO is one of the big ones. It’s made primarily in the small intestine. You can have genetic issues that can impact that. If you have any kind of gut inflammation there, that will affect those small intestinal brush border cells in being able to make it as well. If you have nutrient depletions, too. If we can’t break it down-

I like to think of it as a sink. The histamine coming into our bodies through our foods or that is being triggered and released by the mast cells, that is the water coming out of the faucet. These enzymes are like the drain. If we have water pouring into the sink, and the drain is clear and open and large enough for the water flow, the sink will keep draining, and we are fine. If that water exceeds the capacity of the drain, or the drain gets clogged and gets smaller, the sink will overflow, and we will get those symptoms.

They can be similar because histamine is triggering the mast cells. The mast cells have four different types of histamine receptors. We can get GI symptoms, like acid reflux or diarrhea, constipation, flushing. People familiar with flushing after red wine. When I started getting into nutrition, I got into the Weston A Price work, which is wonderful work. I am a 150% person because I overdo everything. My kitchen looked like a laboratory. I had my kefirs and my cultured veggies and kombucha and raw milk. It’s all high histamine. I couldn’t figure out why I was itching head to toe 24/7, scratching my skin until it bled. I realized I was overdoing the histamine. Let’s dial this back.

Other foods like walnuts, spinach, cashews, peanuts, strawberries, pineapple, we have a thorough list on our website. I want to caution people to use a well-researched list. Dr. Janice Joneja’s work is really good. There is a SIGHI list. A lot of lists online are copied from other lists, and they make mistakes in the copying. About 95% of them have errors. Make sure you use a good list.

That’s histamine intolerance. If all that’s someone has, and they don’t have MCAS, the symptoms are usually much milder.

With MCAS, the symptoms will be more varied, complex, and intense. Someone could have MCAS and not have histamine intolerance. They may have issues with the other mediators with no problems with histamine. I have had some people come through who did a low histamine diet trial for six weeks. I usually ask people to do low histamine and low lectin for six weeks, see if you get a symptom improvement, and then introduce some high histamine foods to see if you get an increase in symptoms. That is the easy way to determine.

If you add in some DAO supplementation- Methylation supports are too tricky in this population, so I don’t do them early. That’s usually about two years into a program. If we get big improvements, histamine intolerance is on the table. I don’t get very many people who just have histamine intolerance. I’ve had a few, but I’m overkill for that, so I don’t see many of those people. They have usually figured it out on their own and are much better just doing those steps and are good to go. You still want to go, why? Why aren’t you making DAO?

I’ve had just a handful of people who only have MCAS without histamine intolerance. Most of my clients have both. They find they do get some symptom relief reducing the histamines and supporting that DAO and other histamine degrading pathways and what’s affecting them. It doesn’t clear it up. It’s not going to do enough.

That’s what I found myself. I followed the low histamine diet for about two years, thinking I found the Holy Grail before I knew MCAS. This will handle all my symptoms. It brought it down a good 20% for me, and it’s still very important. You can recover with that, too. I used to be very limited in the foods I can tolerate. As long as I don’t overdo it, I can have about 10 strawberries. I take my DAO, and I am pretty good to go. That is coming from about 10 foods I tolerated before.

Dr. Eric:

Do you do testing? I know you do genetic testing for DAO. It looks at other things. Do you test for histamine or any other testing related to this intolerance or MCAS?


There is a test, Precision Point Diagnostics for DAO and histamine. It’s a good test. It’s not one consumers can get on their own, so I often don’t talk about it because of that. They can get it through you. That’s a fairly good test. It’s not 100%. If someone is on antihistamines, the histamine may look lower than it would otherwise.

In terms of mast cell mediator tests, I don’t ask people to get it because I am a consulting practice. I don’t diagnose. I don’t need it. But also, the problem with those tests is the histamine, the prostaglandins, and so on, to be accurate, they have to be kept chilled from the time of collection all the way through the processing, including the centrifuge has to be chilled. If not, it’s likely to show negative. These mediators are up and down the bloodstream very rapidly. I have known practitioners who had to get that positive mast cell mediator result for insurance coverage for a patient. They had them trigger a flare, which is always hard on people; then have them come in and sit in the office for eight hours; and draw their blood every hour on the hour hoping to catch that spike. There is still a lot of challenges in that testing. There are people who have access to the cold centrifuge labs and can get those samples handled properly. It’s hard to do.

Dr. Eric:

Could you give some action steps where people could heal from MCAS and histamine intolerance?


I’d love to. The absolute first thing I tell people to do is I have different phases we work through. The first phase is stabilizing. It means that we are going to identify and lower triggers. If that means we haven’t done a clean out the cleaning product, we will do that. Make sure we are not using bleach or bigger trigger items. Clean out personal care products. Make sure the diet is clean. Most of the people who come in to work with me have already done a lot of work on this. I am not usually starting with gluten, sugar, or dairy. Working on those things and processed foods.

Mold exposure is huge. Most people think they have no mold in their home. It’s rare for me to work with someone who doesn’t have mold in their home once we look for it. Many times, people brought inspectors in to check. They tell them there is no mold issue, but they only run an air sample test, which is the least sensitive. They are comparing your spores of mold outside to inside, which makes no sense because- As an analogy, there are a million cockroaches outside. There are 2,000 cockroaches in your house. You are still not going to be happy with 2,000 cockroaches in your house. Same with the mold. We can’t be mold-free, but we need to be out of the toxic molds, the ones triggering to mast cells. The non-toxic molds aren’t as concerning unless you’re allergic. It is hard to find a good remediator and inspector who understands this level of sensitivity to mold.

That is the trigger management side. You talked about stress management before. Toxic relationships. People don’t realize if you are in a toxic relationship with an abusive person, that will keep your body in a fight or flight state as well.

We work on nervous system support. That is very specific limbic system and vagal system work. Both of those systems have to be worked on simultaneously. We can’t just do one or the other. These are much more refined than a YouTube meditation. Keep doing those; those are great. But we are talking about real specific practices here.

Mast cell stabilizing supplements. Some of my favorite starting points- Is your audience really sensitive?

Dr. Eric:

A small percentage. I would say the majority aren’t.


I put my clients into three groups. I will start with the easy category. I don’t get many of those. People who are in the easy category can take some of the combo products out there that are mast cell-supporting. They usually take quercetin. They might be able to handle bromelain or stinging nettle. Those can work. I love the quercetin, perilla seed extract, Chinese skullcap extract. Vitamin D is huge for mast cell stabilizing. Being well hydrated is antihistamine. It’s important.

We mostly work with our sensitive compliance population and our super sensitive people who are struggling with any supplements and medications. Sometimes we will start people with microdosing, and we will take a few granules in water, stir it, and take a couple sips, and that’s it for the day. That entry can be helpful for really sensitive people.

Sometimes when people are super sensitive, I will start them with little sprinkles of baking soda. Baking soda is mast cell stabilizing. Many people have found that it calms down a flare for them if they do a quarter to half a teaspoon of baking soda. If there is high blood pressure, that might not be the right thing for you. Or if someone has extremely low stomach acid, that can make their stomach feel bad. But even sensitive people can do a little baking soda, too. That is our starting point.

All through that, we are looking at what are major underlying issues? What are the root causes? Like we talked about before, if mold is there, I almost always find it if I dig enough, and we look at the right panels for people. Some people are looking at panels that are missing it for them. Then we will address that mold layer.

We have to bring our symptoms down. We have to stabilize first. Once we start detoxing, we will have these swings in symptoms up and down. If someone is way at the top of what they can handle, I don’t want to flare them anymore and have them feeling worse. We will start with some precision targeted binders, going to some liver lymph support. Elimination is key. We have to address the constipation before we do any binders. Then that anti-fungal layer. That lays it out big picture framework.

Dr. Eric:

Thank you so much for sharing. That’s why you said most of your patients, it takes a few years to get them to the point where you are now, correct?


On the really short end for adults, we are looking at a year and a half if they are not too complex and have some short mold exposures. Most people are looking at between 2-4 years. If they are really severe like I was, and I had about 30 years of mold exposures from place to place, that can take about 5-6 years. Generally, people are getting improvements as they go along. There is a very small percentage of people who may not feel better until they get all of the mold out of their system and the Lyme treated. That is the hardest case for the client to stay persistent with. It takes a lot of patience, trust, and faith that this will lead them somewhere. That persistence is key. This is hard work. I know your audience knows that. It’s not just taking two supplements, and you will be done soon.

Dr. Eric:

The big thing is that there is hope. It sounds like you are high on the spectrum of complex conditions. It’s great that you’re giving hope to the listeners with complex conditions.

Beth, where can people learn more about you? Your website is MastCell360.com. Can you repeat some of the resources you mentioned?


We have the symptom survey on the website. We have our foods list if people are looking at histamine and want a lectins histamine list or an oxalate histamine list. We have a Facebook group, a nice community there. People can do both groups. They complement each other nicely. We have courses that get people started. Wellness stabilization steps, the nervous system, and mast cell supporting supplements. We have what I call my MC360 Precision Mold Masterclass. That helps people get started on their mold journey. They may need a practitioner somewhere along the way because you know how complex that is. It needs to be individualized. It helps people make choices and get going.

Dr. Eric:

Thank you so much for doing this, getting together. I’m sure the listeners learned a lot about MCAS and histamine intolerance. Please do visit Beth’s website, MastCell360.com. Sounds like there are some wonderful resources there.


Thank you. I appreciate you having me on and all the work you do as well. We can help people get better faster.