The Mystery of Histamine Overload w/ Dr. Beth O’Hara - Inna Topiler

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The Mystery of Histamine Overload w/ Dr. Beth O’Hara

How Histamine Intolerance Triggers Mast Cell Activation Syndrome

The Case: 

  • Rachel is dealing with digestion problems, sleep issues, headaches, psoriasis, and rashes. 
  • She’s seen a ton of specialists, including a dermatologist, gastroenterologist, neurologist, and an endocrinologist
  • She tried steroids, acid lowering medications, and a Selective Serotonin Reuptake Inhibitor (SSRI) with little improvement.

The Investigation

This battery of symptoms may seem unrelated but I suspected that they were all connected.  My first clue was in her diet – which was not unhealthy but did have one common element that raised my suspicions. It’s found naturally in many foods and many traditional doctors don’t know to look for it – despite the fact that it’s estimated that as much as 17% of the population may have a reaction to it. 

Dr. Beth O’Hara is a Functional Naturopath and the owner of Mast Cell 360, a Functional practice specializing in root cause approach to Mast Cell Activation Syndrome, Histamine Intolerance, and related conditions such as oxalates, mold toxicity, and chemical sensitivities. 

You may recall that Beth appeared on episode 67 when we discussed a case involving oxalates. 

This time we’re focusing on mast cell activation syndrome and histamine intolerance, which I suspected in Rachel’s case. 

What is Histamine Intolerance?

Most people think of allergies when they think about histamines because antihistamines are taken to deal with the symptoms. However, histamine has a much bigger role in the body than reacting to allergens. Histamine helps regulate estrogen levels, the sleep-wake cycle, acts as neurotransmitter, activates stomach acid and plays a role in digestion. The body can build up high levels of histamines to a point where the enzymes that break down histamine can’t keep up. At this point, it exceeds the threshold causing a histamine intolerance that leads to many different symptoms. 

Symptoms of Histamine Intolerance

There are a wide range of symptoms and they vary from person to person. Here are the big ones:  

  • Skin irritation
  • Rashes or hives
  • Headaches (even migraines) 
  • Gastro-intestinal issues
  • Inflammation

Causes of Histamine Intolerance

There are many things that can push histamine levels over the top including environmental toxins and certain foods. Some of the most common foods that are high in histamines include: 

  • Spinach
  • Strawberries
  • Pineapple
  • Fish (especially tinned)
  • Packaged/processed foods
Click here for a comprehensive list of high and low histamine foods. 

In addition to diet and environmental triggers, there are also genetic factors to consider. Specifically the genes that are coded for histamine degrading enzymes like ABP1 and AOC1 that produce diamine oxidase (DAO). Also, Histamine N-Methyltransferase (HNMT) which is another gene with the function of breaking down histamines. 

Alternatively, a gut issue where the microbiome is impeding the natural creation of DAO can also cause a histamine overload. 

What is Mast Cell Activation Syndrome?

Sometimes a histamine intolerance is caused by mast cell activation. Mast cells are the frontline defenders of the immune system and they produce histamine. These cells are activated when there is a threat like a virus, bacteria, parasites, mold or toxins. When they find this issue, they surround it with inflammation producing molecules and call to other immune cells to come in and do the rest of the clean-up process. This activation can result in an over-production of histamine. If the body is under constant attack (from toxins or stress), then mast cell activation can turn into mast cell activation syndrome. This can manifest in many ways with a variety of symptoms and can be difficult to diagnose. 

Testing for Histamine Intolerance and Mast Cell Activation Syndrome

Diagnosing mast cell activation syndrome is to see if there are symptoms involving two or more systems of the body. For example, GI issues, headaches, hives or others listed here. One of the first diagnostic tests is to have the patient take an antihistamine to see if the symptoms are related to histamine. However, you have to make sure that the antihistamine does not have mast cell triggers like dyes or titanium dioxide. The final piece of identifying mast cell activation syndrome is a genetic test showing a positive result for one of the mast cell mediators like tryptase, N-methylhistamine, prostaglandins, or cytokines.

Treating Histamine Overload or Mast Cell Activation Syndrome

The most important step is to reduce histamine intake. This is most commonly managed through a low-histamine diet. It’s important to note that foods that are seen as health-promoting, like fermented foods or spinach smoothies, can in fact be quite high in histamines. Eating organic is also important (to reduce pesticide exposure) as is making sure your protein is clean and fresh. In particular, you want wild caught fish that is frozen at sea. Histamines can be elevated in food over time which is why it’s also important not to eat old leftovers (best to freeze them right away instead of leaving them in the fridge).  And, avoid processed foods especially canned foods (including fish and meat). 

The next step is to make sure there aren’t any other triggers like mold, parasites, bacteria (including in the gut microbiome), or viruses. 

And the final step is to support the body in breaking down histamines. For some this may mean supporting the gut with supplements like DAO  and if needed Betaine HCL, . Dr. O’Hara will also recommend herbal treatments (to patients who aren’t too sensitive) such as Baicalin (Chinese Skullcap) and Perimine (perilla extract) to support the mast cells. Every treatment has to be specific to the individual since the presentation of symptoms and the triggers are often unique to the individual. 

Mystery Solved

As you can see, histamines can play a role in a multitude of symptoms and this was in fact the case for Rachel. 

The first step was to remove high histamine foods from her diet and add a DAO enzyme to break down the histamines. 

Just doing this resulted in a significant reduction in her skin irritations and headaches. But, I suspected that the histamine issue was secondary to other imbalances. 

We ran an organic acid test and a stool test and saw she had a lot of Candida. She was already eating well and didn’t over consume starches or sugars so we worked on it through supplements. I used GI Microb-X, FC Cidal and Tricycline followed by SF 722 for candida eradication and then we put in probiotics, glutamine and Enterovite for healing. 

We also ran a mycotoxin test and saw she had several elevated mycotoxins (mold toxins). She suspected her apartment had issues as she saw spots on her bathroom ceiling. Thankfully, her lease was almost up and she was able to move away from the issue. We then used Molecular Hydrogen and Ultra Binder to help bind what was left in the body and support the mitochondria which can often be affected by mold.

Happy Ending

After 6  months on the protocol, Rachel had clear skin, better digestion and improved sleep. After the healing that we did, she was able to go back to eating tomatoes and avocados (high histamine foods) with no issues. She finds that she still needs to be mindful and doesn’t overdo high histamine foods but she no longer needs to completely avoid them like before.

Eliminating Health Mysteries

For Rachel we were able to find that missing piece of the health puzzle and help her completely regain her health. Could histamines or mast cell activation syndrome be the missing clue for you or someone in your life? 


Resources mentioned

Thanks to my guest Dr. Beth O’Hara. For more information on Mast Cell Activation and Histamine Intolerance, visit her website where you’ll also find her Symptoms Survey and Histamine Foods List.  Or, connect with her on Facebook.  

Suggested Products:

GI Microb-X, FC Cidal Tricycline 

SF 722 

Probiotics Glutamine


Molecular Hydrogen 

Ultra Binder Betaine HCL

Related Podcast Episodes:

The Case of Hidden Mold w/ Dr. Tim Jackson
Underlying Causes of Recurring Candida w/ Dr. Michael Biamonte
Unconventional Ways to Boost Immunity & Fight Coronavirus Fears w/ Dr. Mario Martinez
The Case of the Teacher Who Was Always Sick w/ Dr. Mario Martinez

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