I’ve learned a lot about histamine intolerance and its many symptoms over the past two years. Since I dropped the plants and started eating a carnivore diet back in 2022, I’ve come to realise just how much histamine has been affecting my physical and mental health – both today, and in the past, prior to my embarking on a meat based diet.
When most people think of histamine intolerance, they think of a running nose, streaming eyes, and maybe hives or some other sort of rash. But what I’m about to share with you today is so much more than that. Too much histamine can cause many symptoms that are generally not realised or recognised by the wider public, OR your doctor!
The Experience that Prompted this Article
I woke up one morning just a couple of months ago, and it was a good day. I felt amazing! In fact so much so that I commented to my husband that I was feeling super calm and relaxed, and that I wished I could feel like this all the time. It was bliss…
It was bliss for me because feeling this relaxed always stands out. It’s not my normal state.
A lifetime of living with many symptoms of Pyroluria has meant that my ‘normal’ is a kind of slightly strung out, holding it together, looking calm on the outside but messy on the inside, ‘fearful for no reason’ kind of existence. And that’s what I’m used to. So when that changes, and actual real relaxation kicks in, it seriously feels like bliss to me.
So on this particular morning I felt amazing. I had a sauna, did some red light therapy, and then I ate my first meal of the day around lunchtime. My first client for the day was coming for a massage after lunch.
I ate two lamb shoulder chops that I’d had dry brining in the fridge for 24 hours. I’d been eating a bit of dry brined meat over the past couple of weeks, and quite a bit of pork belly as I was experimenting with a high fat version of the carnivore diet.
Sudden Mood Change After Eating
After I finished those lamb chops I noticed that within minutes my mood changed. On reviewing the prior couple of weeks I’d been noticing that happening quite a bit. I felt annoyed and agitated…. Kinda grumpy, and my husbands conversation was really bugging me.
My client was due about an hour after eating lunch and during that hour I had several trips to the toilet with loose bowels. My anxiety was rising, and I was feeling stressed out.
That wasn’t unusual though. I’ve had a lifetime of anticipatory anxiety. These days it happens often before my first client of the day, and although it drives me a bit nuts, I’m used to living with it. It affects my bowel, which then affects my mind and my anxiety levels – more. But I know that most of the time, once I’m working it settles down. However this day, it didn’t.
My client arrived and after a short chat, I visited the toilet again while she got herself undressed and onto the massage table. I returned to the room and started her massage. But instead of my mind and body calming down as they usually do, everything got worse. Much worse…
Before I knew it I was desperate to go to the toilet again, and I was having a full on panic attack. I felt like I couldn’t breath and had to excuse myself.
I went to the toilet where I sat and tried to calm myself. Before returning to my treatment room I took some activated charcoal capsules to try to slow down my bowel (I’d already taken some prior to her arriving as I often do), and I probably used some Rescue Remedy or relaxing essential oils to try to settle things down. I don’t remember.
I returned and apologised, and carried on with her massage. She was content, relaxed, and blissfully unaware of what had just happened in my world. It took about 45 minutes of her one hour timeslot for my mind and body to settle down. And while I worked, I examined in my mind what had just happened.
What did happen??? How did I go from so blissfully relaxed, to an internally hysterical mess after eating two lamb chops for lunch? I’ve felt like this before. Many times… But because I’d been SO good earlier, the difference between those two states and the speed at which my state changed made it clear to me that the food had triggered the change.
But why?…
The Many Symptoms of Histamine Intolerance
The symptoms of histamine intolerance include not only allergies or hayfever, but also anxiety, depression, panic attacks, gut issues, and diarrhea – all symptoms that have affected my life for many years.
But that’s not all. Just like one of those knife ads on TV, there’s more! Other symptoms of histamine intolerance may include:
- shortness of breath
- asthma
- itching
- hives
- runny or stuffy nose
- sinus congestion
- headaches
- migraines
- period pain
- generalized pain
- nausea
- vomiting
- irregular heart rate
- arrythmia
- tachycardia
- flushing
- low blood pressure
- difficulty regulating body temperature
- dizziness
- diarrhea
- constipation
- flatulence
- fatigue
- high blood pressure
- swelling of tissues
- inflammation
- weight gain
So as you can see, there is more to histamine and the symptoms it can cause than most people realise. In fact I suspect it’s a much bigger problem and more common than we might think. It’s also (obviously) often being treated with drugs that do nothing to resolve the underlying problem, and will probably only serve to make the symptoms worse. Histamine intolerance can certainly be the cause of many symptoms both within, and outside of the carnivore community.
What Causes Histamine Intolerance?
Histamine plays an important role in our body. It’s part of our immune system, and we’d be in trouble without it! But when histamine gets too high and our histamine bucket overflows, it can cause symptoms. So although it is commonly referred to as ‘histamine intolerance’, the problem we experience is not really that we’re intolerant to our own histamine. The problem is caused by too much of it floating around in our body. Whether from eating too many high histamine foods, or because our body isn’t able to break it down efficiently, or both.
Histamine is released by basophils and mast cells found in many places in the body. It is a signaling chemical our immune system releases to send messages between different cells.
While best known for creating allergy symptoms, histamine has many important functions such as regulating your sleep-wake cycle and cognitive function (which is why some antihistamines make you sleepy and drowsy).
Histamine also regulates countless bodily functions and plays a key role in your body’s inflammatory response. The effect histamine has depends on which histamine receptors it binds to.
The Role of Histamine Receptors
We have different types of histamine receptors that do different things in different areas of our body. These are known as H1, H2, H3 and H4 receptors. So let’s look at these histamine receptors and what they do.
H1 Receptors
You have H1 receptors throughout your body, including in neurons (brain cells), smooth muscle cells of your airways and blood vessels. Activation of the H1 receptors causes the well-known allergy and anaphylaxis symptoms. These are symptoms such as:
- Itchy skin (pruritus)
- Expanding of blood vessels (vasodilation)
- Low blood pressure (hypotension)
- Increased heart rate (tachycardia)
- Flushing
- Narrowing of your airways (bronchoconstriction)
- Pain
- Movement of fluids through blood vessel walls (vascular permeability)
H1 receptors also regulate or influence:
- Sleep-wake cycles
- Food intake & appetite
- Body temperature
- Emotions
- Memory
- Learning
H2 Receptors
H2 receptors are found mainly in the cells of your stomach, smooth muscle cells and heart cells. Activation of the H2 receptors is responsible for:
- Stomach acid secretion which helps with digestion
- Stimulation of mucous glands in your airways
- Vascular permeability
- Hypotension
- Flushing
- Headache
- Tachycardia
- Bronchoconstriction
H3 Receptors
H3 receptors are found in neurons and are involved in the function of the blood brain barrier, regulation of the release of histamine, and of important chemical messengers such as dopamine, norepinephrine, acetylcholine, glutamate, and GABA.
H4 Receptors
H4 receptors are found in the bone marrow and play a role in the formation of new blood cells, and the regulation of the immune system and inflammation.
The following image provides a simple visual of the many histamine intolerance symptoms that might be triggered depending on which histamine receptors are activated.
Source: https://ajcn.nutrition.org/article/S0002-9165(23)28053-3/fulltext
So What Causes High Histamine?
What I’ve learned is that there are many things that can cause or contribute to high histamine levels in the body, or that may make us more prone to having histamine issues. These are commonly things such as:
- Gastrointestinal (GI) disorders: IBS and other gut issues
- Medications – Some medications can temporarily block DAO functions or prevent production
- Bacterial or fungal overgrowth – SIBO or SIFO
- Mold toxicity and CIRS
- Diet – Consuming aged foods such as alcohol, fermented foods, avocado, eggplant, spinach, egg whites (raw), processed or smoked meats, canned fish, aged cheese
Genetics and Histamine Intolerance
There are also genetic variations that can make us more prone to histamine intolerance. These genetic variations may cause either a lack of DAO enzyme or dysfunctional DAO.
DAO is the abbreviation for Diamine Oxidase which is the enzyme that breaks down histamine in our body. DAO is both made in the body, and can be supplied in some of the foods that we eat.
But if we have genetic variations that affect the production of DAO or that cause our body to make dysfunctional DAO, then we may not break down excess histamine effectively causing our bucket to overflow.
On investigating my own genetic information, it seems that I have at least three gene variations that can affect histamine and DAO in the body. The first and possibly most impactful (from my understanding) is the DAO gene rs10156191 (mine is rs10156191(C;T)), also known as Thr16Met. My histamine levels may also be affected by my MTHFR genetic variations, and rs6323 which affects Monoamine oxidase activity.
Now my understanding of these genetic variations is limited, but it seems to me that some of my genes are potentially influencing my ability to break down histamine. But as always, diet and lifestyle play a huge part in how these genes function. So how can we lower our histamine levels, and improve our symptoms?
Curing Histamine Intolerance
Can you cure histamine intolerance? Well if we have a predisposition or dodgy genes that affect the breakdown of histamine, then maybe ‘cure’ isn’t the right word. But we can certainly manage it, and we may even be able to eliminate histamine intolerance symptoms completely. But it’s going to take some time, education, and some serious commitment to improving our diet, physical and mental health, and of course, healing our gut is key.
I’ve learned a lot about reducing histamine intolerance symptoms over the past two years, and the following is some of what I’ve learned and that might help you if you’re suffering.
Histamine Foods to Avoid
The first recommendation is always to avoid aged foods and foods that are higher in histamine. This includes:
- Alcohol
- Aged cheeses
- Leftover foods
- Fermented foods such as yogurt, kefir, sauerkraut, kombucha
- Smoked meats and other foods
- Canned fish
- Aged and cured meats
- Pork
- Eggplant
- Spinach
- Avocado
- Dried fruit
- Tomatoes
It also may be a good idea to avoid gluten as new research suggests that it can cause histamine-type symptoms in some people. As with all suggestions around food, doing your own N=1 experiments to see how your body reacts to various foods is always going to be a good idea.
Other foods and drinks that can cause histamine symptoms or block DAO production, include chocolate (which interestingly used to make me depressed the day after I ate it), citrus fruits, food additives, black tea, yerba mate, and coffee. The caffeine in these common and much loved beverages can contribute to histamine intolerance symptoms and apparently inhibit DAO.
It is also worth noting that many of the strains used in probiotic supplements can actually make histamine issues worse. If you want to take a probiotic that can help reduce histamine levels, check out my list of recommendations at the bottom of this article.
Medications and Histamine
I haven’t looked too much into medications as I personally don’t take any. But when I was digging into information about histamine, and anxiety and depression, I discovered that some anxiety medications and anti-depressants block H1 receptors in the brain. (Is this at least in part how they work?)
This seems crazy to me as histamine can cause anxiety and depression, so why are doctors not taught to speak to their patients about histamine before they put them on these drugs. That just seems like common sense to me – but I guess it’s not as profitable!..
A quick Google search also shows that many medications actually make histamine issues worse.
What Can YOU Do to Reduce Histamine Symptoms?
The following are some basic steps that you can take to reduce your histamine load:
- Reduce problem foods and drinks!
- Consume supplements and herbs that help clear histamine from the body
- Drink plenty of water
- Consume kidney or kidney supplments (kidney contains DAO)
- Take a DAO supplement
Studies also show that using a natural unrefined salt can help to lower histamine, and there are a number of herbs that may also help. These include Ginger, Stinging Nettle, Black Cumin Seed, and Neem.
Heal Your Gut
Finally, the single most important thing to do to resolve histamine intolerance issues is to heal your gut! If your gut isn’t healthy, you’re not healthy. It is literally the centre of your whole being, and affects the rest of your body and how it functions.
But how to do I heal my gut?
Going by my personal experience (and the experience of many others) the carnivore diet is a great start! And for many people, given a little time, that might be enough.
But for those of us who have a bit more going on in our bellies, we might just need a little more help. Focusing on curing SIBO can help. I’ve made a few videos on how I’ve done that (you can check out my SIBO playlist here), and the other thing I’d now strongly suggest is using colostrum.
Colostrum has many health benefits, and one of those is healing the gut lining. It does a great job of that!
But a word of advice for anyone starting on colostrum – start slowly! If you have gut issues, start with just a quarter teaspoon of colostrum and work your way up. I didn’t do that initially, and oh boy! I had a few miserable days… I had to back off to a quarter teaspoon dose.
Patience may be required but it’s worth sticking with it. I’ve linked the colostrum I’m using below as well as another quality brand.
Supplements for Histamine Intolerance
Colostrum (NZ) – https://homegrownprimal.co.nz/collections/grass-fed-beef-supplements/products/colostrum
Colostrum – https://amzn.to/3RtO7mJ
Black seed oil – https://bit.ly/black_cumin_seed_oil
DAO – https://amzn.to/3VGFuHE
Probiotic – https://amzn.to/3VmSAbL
This has ended up being a much longer post than I’d anticipated. I hope you’ve found it helpful! If you have any questions or comments, feel free to pop those below.
