
Histamine Intolerance (HIT) – Everything you need to know!
In this blog post we are going to examine all the information you need to conquer Histamine Intolerance.
Not only will we explore how I cured my own histamine intolerance, but I will teach you the exact step by step instructions from:
Symptoms, Diagnosis, Management and eventually Cure.
Prepare yourself for some never before seen infograpics, interactive food lists, templates and all round “A-ha” moments.
Access the FREE Histamine Care Package I wish I had when I first started to experience my histamine intolerance symptoms.
But first…
Allow Me To Introduce Myself
Ok. So I know what you are probably thinking. This all sounds too good to be true! Right?
All this information, free templates and a complete histamine care package.
All created by someone who has actually come out the other side of this long, emotional roller coaster.
“So who is this guy? And why does he care so much?”
My name is Mike. I am a gym manager, personal trainer and physical therapist living in Galway Ireland. I used to have a histamine intolerance but eventually I found out how to fix my problem.
This is me in full Cringey HD. I published this video to Youtube almost 3 years ago. A time in which I was still clearly experiencing symptoms.
It was around this time that I promised myself to get to the bottom of this miserable condition.
Invisible illness or Imaginary illness?
The truth is I have been putting off writing this blog post for a very long time.
Although I managed to cure my own histamine intolerance I still feel guilty discussing it.
I have had HIT for a very long time. I’ve experience the fatigue, anxiety, migraines and rhinitis etc…
Not to mention trying to justify my symptoms to friends and family.
Since the time of making this video I have figured out how to manage my symptoms. Now, whenever I talk about this invisible illness, I feel people assume it was always more of an imaginary illness.
This ‘impostor syndrome’ however, comes paired with a sense of responsibility.
If I have identified a road map for curing my own histamine intolerance, shouldn’t I at least go back down the histamine rabbit hole and try to sign post the the right way out for everyone else?
I believe I have a responsibility to pass on the information I have collected over the past few years.
And so I created this “Ultimate guide to histamine intolerance.”
This guide might not work for every reader. However, If I can pull just one bunny out of the histamine rabbit hole, then the past 8 weeks illustrating this blog post will have been worth it.
The 4 Step Guide to Healing Your Own Histamine Intolerance
Before we get into the nitty gritty, I want to give you a brief overview of each section in this this guide.
Then, we will explore each step in a more detailed and illustrated fashion.
Before finally ending the guide with a solid conclusion and sending you off with your very own “histamine care package”
- Research and Recognition
In Step 1 I will teach you all about Histamine Intolerance and show you how to identify the symptoms. Hopefully we can fast track your learning curve by linking to the best resource you will wish you had found sooner.
- Diagnosis
In Step 2 you will learn the complicated nature of diagnosing Histamine Intolerance. Through a clever process of elimination you will be able to find out if its actually a histamine intolerance causing your symptoms or some similar condition. I have attached an easy to follow flow chart.
- Managing Histamine Intolerance
In Step 3 We explore the various tactics and strategies I have used over the years to control my histamine intolerance. This is a priority based list of what matters most, and what isn’t worth the effort. Hint: Diet is NOT top of the list.
- Reintroduction and healing
Finally, Step 4. This is the big one. In this section I arm you with a complete interactive nutritional template so you can formulate your own elimination diet and then reintroduce the right foods at critical times.
This is the Ultimate Histamine Intolerance Care Package.
Step 1: Histamine Intolerance Recognition and Research
Recognize that you actually have a Histamine Intolerance
I spent about 3 years suffering from a histamine issue before I even knew Histamine Intolerance existed!
Because of the cyclical nature of histamine symptoms, I wasn’t entirely sure there was actually something wrong with me. These symptoms gradually got worse over time and were no long as easy to ignore. I suffered from morning sneezures, chronic anxiety and constant fatigue and thats only the tip of the iceberg.
It wasn’t until I was visiting my family for Christmas in 2014 that I begin to recognize that there may be something wrong with me. Although it was December and I was on an enclosed train carriage I was crippled with hay fever like symptoms.
I spent the entire holiday either dodging relatives or finding the time to take a power nap.
“I am a physically fit personal trainer in my early 20’s”, I thought to myself. Surely I should have more energy than this?
I spent the remainder of the Christmas holidays with these health concerns. Although I didn’t have a clue where to begin, I was determined to find the root cause of these symptoms.
Going down the research rabbit hole
Once the holiday season had passed I began to do some research. I spent the next 6 or so months trying to get to the bottom of my symptoms.
Approaching doctors was way harder than I thought. It was very hard to explain the many symptoms that seemed to fluctuate depending on the time of day.
Most of the time I would be diagnosed with run of the mill hay-fever, or just given painkillers for my migraines.
Although histamine intolerance affects approx 1 in every 100 people, very few individuals get fully diagnosed.
Histamine intolerance symptoms can replicate that of a common cold, hey fever or even food allergies.
Unfortunately causing HIT to be mislabeled.
The Final Piece of the Puzzle
I tried talking to friends and family about my illness. Although they were very supportive, none could give me the answers I needed.
My aunt had been in contact with a German doctor a few years prior. At the time she was seeking treating for her husbands psoriasis.
At that time she collected many documents, articles and research papers from the doctor. Although she never got around to reading them all, she recalled the term “histamine” in the one title and instantly made a connection to my allergy type symptoms.
‘This may be the last piece of the puzzle” She said, as she handed me the coffee stained print out titled:
“AK and the Histamine Problem”- Dr.Wolfgang Gerz
The Eureka Moment
This single Article was a game changer for me. I read the paper, front to back numerous times. In just two short pages Dr.Wolfgang clearly explained everything I needed to know about the histamine problem.
Finally I was able to recognized and understand that I wasn’t crazy. The symptoms were real, and I most likely suffered from a histamine Intolerance.
I often emphasis the first part of this guide as being the most difficult. This is because the step one, “Recognition”, is largely left to chance.
It’s very difficult to diagnose a condition you do not even know exists. Especially when histamine intolerance can be masked by or married to other medical conditions.
Unfortunately most people will never experience this same eureka moment I had when my aunt handed me that medical paper.
Do your homework on Histamine Intolerance
Once you realize histamine intolerance is actually a thing. A real medical condition that effects 1% of the worlds population. You can finally begin to get to work on finding a cure!
But first, you must create a foundation of knowledge on the topic of histamines and histamine intolerance. This knowledge will allow you to take back control and finally kick histamines ass!
When I first recognized excessive histamine as a condition. I went deep down the Google and Youtube rabbit hole. I literally read every blog post and viewed every video.
Like most nutritional information found online there are some conflicting viewpoints. However, over the years I find myself continually answering the same few questions by fellow HIT Students. (HIT=Histamine Intolerance?)
Histamine Frequently Asked Questions
Here’s a list of F.A.Q’s that are fundamental to your knowledge.
Please, if you have any questions yourself, ask them in the comment section below. I will make sure to come back and update this list regularly.
‘Histamine’ is an organic compound produced by all mammals for various different reasons.
In Humans, it is a mediator substance in most allergic responses and bodily injuries.
Because histamine is derived from the amino acid histidine it can be found in most foods.
The quantity of histamine in the food largely depends on they type of food, and how fresh that food source is.
The truth is, anyone can experience the symptoms of histamine excess.
That is, when an individual temporarily has too much histamine in their system.
This can happen from time to time in individuals without actually having a histamine intolerance.
The main difference between this momentary overload of histamine VS a true histamine intolerance is in the sensitivity level of the individual.
A person with true histamine intolerance will be far more sensitive to histamine overload than the average person. Which will cause more frequent outbreaks.
The constant allergy type symptoms can be almost as mentally draining as it is physical. Which can have huge consequence for an individuals quality of life.
I always emphasis the difference as being that of momentary overload vs chronic overload.
If you find yourself suffering from the symptoms of histamine excess more than the average person than you probably have a histamine intolerance.
The most common cause of histamine intolerance is a deficiency in an enzyme called Di-amine oxidase (DAO for short). This enzyme, when located in the digestive system, is responsible for breaking down the histamine we eat.
Less common causes of histamine Intolerance are:
-Mast Cell Activation Disorder (MCAS)
-Mastocytosis
-MTHFR Gene Mutation
This blog post specifically refers to Histamine Intolerance as caused by a deficiency in DAO.
In the next section I will discuss how you should approach identifying the primary cause of your symptoms.
Our body has a natural internal production of histamine. We also take in extra histamine from the foods we eat. Because of this, the total histamine in our body will fluctuate from one end of the day to the next.
When this level gets too high, and we can no longer handle such large quantities of histamine, we may experience adverse reactions. These reactions serve as a signal that our internal histamine levels are currently too high.
I recently posted a survey to an active Histamine Intolerance Facebook group.
From this survey we have identified the most common symptoms inindividuals suffering from Histamine Intolerance. You can see from the survey results below.
87% of Individuals who suffer with HIT experience fatigue as a primary symptom.
Please click the image link to take the survey yourself. I regularly email further insights and and information about these answers.
Now that we understand the basics of how histamine intolerance occurs we can begin to discuss a solution to the problem.
Ultimately your goal should be to solve the root cause of this issue. Most of the time being this is a low DAO production.
Although it sounds like a simple goal, the process we must take to get there is a little more nuanced.
DAO production typically gets reduced as a result of various nutritional deficiencies.
If we are to boost our natural DAO production we need nutrient dense foods to increase any deficiency that may be causing the problem.
This is a challenge in and of itself.
How do you go about eating the correct nutrient dense foods if all foods have their own unique histamine levels?
The solution is a smart nutritional strategy.
First we must eliminate all your HIT symptoms. We do this by removing as much histamine, and other contributing foods from the diet as possible.
Then, once you experience relief, you begin to reintroduce high nutrient, low risk foods.
This will promote the production of DAO.
I know it all sounds very complicated.
That’s why I have designed the “Ultimate Histamine Care Package”, to make this as easy as possible.
In the next 3 Steps I will outline the exact process you can follow to relive your histamine intolerance symptoms and begin to heal your natural DAO production.
Step 2: Diagnosis Through The Elimination Diet
Unfortunately there is no way to clinically test for a Histamine Intolerance or DAO deficiency.
As we found out earlier, histamine and DAO levels can fluctuate massively from one end of the day to the next.
Blood test will only give you a snapshot of the DAO and histamine at one moment in time.
For this reason, a blood test will never paint a true picture of weather or not you have chronically low levels of DAO.
Of course you can still technically get these blood tests done. However, they won’t actually provide you with the information you need to move forward.
That being said you can still work with a Registered Dietitian for an official diagnosis. As long as they are experienced in histamine intolerance of course.
This is done through deductive investigation of your diet.
Currently the gold standard test for checking an individual for HIT is in the formulation and implementation of an elimination diet.
Please note: An elimination diet is not just a low histamine diet. Unlike a low-histamine diet, an elimination diet will account for a large spectrum of factors contributing to your symptoms.
If your symptoms subside while following a correct elimination diet you may then be diagnosed “Histamine Intolerant”.
Diagnosis Flow Chart
You should follow this procedure of testing if you suffer from year round allergy type symptoms or suspect you have HIT.
When you first notice symptoms you should consult a qualified medical professional.

The first test I would recommend is an allergy test. You should request allergy testing for various types of foods and even environmental allergies such as grass, animal dander, dust mite etc…
If you do in fact have an allergy, your first port of call should be to limit contact with that specific allergen.
If you find your symptoms are still present, you may want to proceed with an elimination diet.
This will remove any ingested histamine from the equation and allow you to isolate and test a DAO deficiency.
If your symptoms improve after following a well formulated elimination diet then you most likely have a histamine intolerance as caused by a DAO deficiency.
If you do not see the Symptoms improve despite your 100% compliance to the diet you should pursue further testing to rule other other less common causes of your symptoms.
Such as Candida Overgrowth,MTHFR,Mastocytosis or MCAS.
Once the elimination diet has done its job and reduced histamine intolerance symptoms you should begin the final step. The reintroduction of high nutrient, low risk foods.
My Official Diagnosis
I was never officially diagnosed with histamine intolerance. In fact, I do not think an ‘official’ diagnosis is necessary to progress with self care for this condition.
From my initial research on I was almost certain that this was the cause of my problems.
To test this theory properly I formulated my own elimination diet.
DISCLAIMER: I have plenty of experience in nutrition. I am a qualified personal trainer and neuromuscular physical therapist. I have helped hundreds of people with their nutrition and health. Of course, with enough effort you too can create your own diet. However, if you have the means, please seek the advice of a medical professional.
After a few short weeks following an elimination diet my symptoms almost completely disappeared.
I distinctly remember telling my friends one day, that I had never felt better in my life.
The brain fog, anxiety, fatigue and sneezures had vanished. I was finally free to see how much this condition had actually been affecting my life.
When I followed a strict elimination diet, even though its nutritional value was very low, I felt 100 time better.
It had to be a histamine Intolerance.
How to create your own Elimination Diet
The primary feature of an elimination diet is to leave no stone unturned. You must do everything in your power to alleviate symptoms.
Even if that means a very rigid, boring and non balanced diet.
The elimination diet is used to experience momentary freedom from the symptoms of histamine intolerance.
For this reason we do not stay on an elimination diet long term.
When the elimination diet is successful, it will grant you the energy to move onto the next step. That is, healing your natural DAO production via a more nutrient dense diet.
Often, an elimination diet is confused with a more general low-histamine diet. While eating low histamine foods is important.
It is only a fraction of the elimination diet formula.

- Low Histamine Foods
As I mentioned earlier. All foods have a natural histamine count. Some foods are higher/lower than others.
When formulating your own elimination diet you will want to only eat foods that are low in histamine count.
To make this as easy as possible I have created a “Low Risk” safe food list in the Histamine Care Package.
High Histamine Foods Examples:
Spinach,
Tomatoes,
Cheese,
Wine,
Avocado Etc….
This part usually shocks people. Although these foods may be classed as healthy. They are in fact super high in natural histamine!
- Histamine Liberators
A histamine liberator is different from your general high histamine foods. A histamine liberator type food can contribute to filling your bucket despite the fact it is actually quite low in Histamine.
Histamine liberators are substances or foods that stimulate the release of inside your body. These foods and food additives may significantly contribute to overflowing your bucket and as such need to be controlled on an elimination diet.
Examples of Histamine liberators include:
Strawberry,
Benzoates (In pretty much every kind of soft drink)
Pineapple,
Stress Etc…
The foods found on the low risk food list are free from histamine liberators. - Histamine Competitors
Finally we have histamine competitors. Earlier I explained how an enzyme in the gut called diamine oxidase breaks down histamine ingested histamine.
Well that’s not all this enzyme breaks down. Truth is, DAO has a very demanding Job!
When we eat certain foods containing large amounts of other amines our DAO is also required to aid digestion.
And if your limited DAO is already being used in digestion there won’t be enough left over to combat ingested histamine.
Remember! You do not have enough DAO to do everything!
A lower than average DAO production is the main reason you suffer with histamine Intolerance.
For this reason we avoid foods that compete for our precious DAO.
Examples of foods that compete for DAO:
Bananas,
Chocolate,
Oranges,
Cashew Nuts
Etc…
Luckily for you, the safe “Low Risk” food list is also free from histamine competitors.
An Elimination Diet Is Not A Forever Diet
I know what you are thinking. “Well then, what the hell am I supposed to eat?”.
The elimination diet is not a forever diet. If you follow the steps correctly you will be soon be able to tolerate most foods.
Trust me, when you follow a well formulated elimination diet you will be given a new lease of life.
Knowing this feeling, and the exact diet you used to make it happen, will be essential for the next step on your recovery journey.
Step 3: Managing Histamine Intolerance

Now that you are positive you have a histamine intolerance, and you have ruled out the other potential causes of your symptoms, you need to learn how manage your condition.
To successfully manage histamine intolerance you should create a lifestyle that further mitigate the most common histamine triggers.
This is a critical for success in the final step of this guide.
You need to empty your histamine buckets as much as possible so we have wiggle room to introduce new foods without histamine overflow.
4 Main Causes of Histamine Build up
A) Personal Allergies (Environmental and Nutritional)
B) Protein Quantity
C) Stress Management
D) Diet
Your ultimate success in the healing phase is contingent on the control of these 4 main triggers.
Each individual trigger, can be just as bucket filling as the highest of histamine foods.
In Step 4 you will begin to experiment with more nutrient dense foods.
Your goal is to reintroduce individual foods one at a time.
If your symptoms begin to reappear you will need to be certain that the newly introduced food is actually to blame, and not failure to control any of the above factors.
You MUST control as many of the variables as possible so that you can carefully identify which foods you can, or cannot tolerate.
A) Personal Allergens
When the body comes into contact with an allergen it has an immune response to protect itself.
This causes mast cells to dump stored histamine which will quickly over flow your bucket. Especially in the histamine intolerant. The people with lower than usual DAO.
The symptoms of histamine intolerance and allergies are one in the same. This is why most histamine intolerance goes unrecognized.
Often histamine intolerance is mistaken for environmental or seasonal allergies. Despite allergies being only one part of the overall HIT equation.
When you identify your own personal allergies you can begin to structure your lifestyle to control for those allergies.
The fact of the matter is this. You can be on the ultimate elimination diet and still experience zero results.
If you are constantly coming into contact with an allergen your bucket will overflow despite having the perfect diet.
Allergies are powerful histamine triggers that MUST to be recognized to be controlled.
I found out I was allergic to cats, grass pollen, and extremely allergic to dust mite.
It took me a while to figure out how to structure my lifestyle around these allergens but eventually I figured it out.
I know you can too… Get the test done as soon as possible. Then get to work to limit exposure to your own unique allergies.
B) Protein Quantity
Eating excessive protein is perhaps one of the more common triggers of histamine.
Unfortunately this aspect of nutrition is frequently overlooked by the Histamine Intolerant.
Protein quantity, that is how much protein you eat, will play a major role in controlling your overall histamine levels.
At the beginning of this blog post I explained how histamine itself is derived from the amino acid histidine.
Amino acids are the building blocks of all protein we consume.
Histidine is an essential amino acid, meaning our body cannot create it itself and as such must come from food sources.
Histidine is abundant in many of the food sources we eat. When we eat protein in excess, our bodies will covert histidine to histamine.
Protein is important. However, excessive protein is still huge trigger for a histamine release.
For this reason I suggest eating anywhere between .5-1g of protein per pound of body weight. Depending on how physically active you are.
If you exercise regularly you should eat a little more. If you are quite sedentary then you need less.
C) Stress Management
I hate to say the cliched phrase “Stress Management”. But, controlling your stress levels, is crucial for controlling internal histamine levels.
We have seen earlier that stress itself can play a huge role in triggering a histamine response internally. Particularly as an immune response to local trauma or allergic reactions.
I want to make sure this blog post contains actionable information and not just cliched self help advice.
For this reason I would encourage all readers to get at least 8 hours sleep a night.
Sleep deprivation or sleep stress will be a huge contributing factor to all around stress. If you prioritize sleep hygiene you stand a far greater chance of controlling all round histamine levels.
The food choices, and inherent stress response from poor sleep hygiene can be one of the key factors contributing to your histamine symptoms.
Developing a routine around prioritizing sleep is one of the fastest, yet most overlooked solutions to eliminating histamine reactions.

Step 4: Reintroduction and Healing
Once you have learned how to control your symptoms and implement an effective elimination diet you should experience a temporary relief from HIT symptoms.
The elimination diet is nutritionally restrictive and as such may cause further problems down the line if followed for an extended period of time.
Remember, the root cause of most histamine intolerance is nutritional deficiency leading to underproduction the Enzyme DAO.
By now, you should have learned how to successfully drain your histamine bucket as much as possible.
Although your tolerance is very small, you will have created some room for experimentation, that otherwise wouldn’t exist.
With an empty as possible bucket you can begin reintroducing certain foods to promote the production of diamond oxidase.
Reintroduction of New Foods

While your histamine bucket is as controlled as possible you can reintroduce individual foods without causing your bucket to over flow.
Make sure to only add 1 new food every few days. Once a food is added, and histamine levels are under control, you can try to add another food.
The trick to success in the reintroduction stage is adding high nutrient low risk foods in order.
The first foods should have the most micro-nutritional value while taking up as little space in your histamine bucket as possible.
To make this phase of your nutritional journey as easy as possible I have compiled an interactive food list of 60+ food graphics in the exact order of reintroduction.
Conclusion
Histamine Intolerance is a real medical illness that affects approx 1 in 100 people. Often times it goes unrecognized or undiagnosed due to it mirroring the symptoms of other more common conditions.
However, HIT is far from temporary. For most of us it is a year round struggle of combating allergic type symptoms with an ever reducing food list.
I have seen time and time again, people losing hope in the face of this condition. Most of the time they simply do not understanding how it is caused or managed. Let alone cured through a smarter nutritional strategy.
Please share this guide, using the image below, to those of your friends and family who seem to constantly suffer from allergy type symptoms.
It may be the last piece of the puzzle that they need to experience much needed hope and relief.
If you have any questions or comments please write them below. I will be happy to reply as soon as I can.
Happy healing,
Michael
Please send me a copy of the Histamine Care Package
Hey Carol!
Glad to hear from you!
You can access the Histamine Care Package using the following link
https://graduatefitness.com/histamine-intolerance-care-package/
Please email me Mike@graduatefitness.com and I will be happy to give you the password.
I hope this helps.
Mike