Anxiety? Rashes? Bloating? IBS? Reflux? Migraines? Allergies? Weight Gain?

You might have Histamine Intolerance.

What the hell is that I hear you ask and how is it all connected to Histamine? Well, Histamine is the chemical messenger that we all know makes us itchy, rashy and sneezy – not normally something we would attribute to ‘health’. However, as it also acts as a Neurotransmitter in our brains, we do require a normal amount of blood Histamine for healthy functioning.

Histamine wears many ‘hats’ and causes lots of different effects in our bodies. It can be responsible for the following:

  • Regulation of our sleep-wake cycles
  • Helps to release Gastric acid for digestion
  • Promotion of libido and healthy mood
  • Decreases our GABA levels (our calming chemical in the brain)
  • Increase Norepinephrine and Epinephrine levels (known to be responsible for anxiety & the fight-or-flight response)
  • Change in Neuroendocrine function – effecting the Thyroid, behaviour, energy metabolism, thermoregulation, fluid balance, stress, and reproduction.
  • There is even some research to suggest that Histamine may cause an increase in the permeability of the blood-brain barrier (making it easier for other chemicals to cross into the brain).

When Histamine levels build-up in the body over time, you can experience a ‘spill-over effect’ and symptoms can start to appear.

For some of our clients, they are obvious like rashes, itching, sneezing, hives, Asthma etc. But for most we find they are often a lot more hidden and easily explained away as other concerns. Anxiety, Migraines, Headaches, period pains and even Diarrhoea, Reflux and Bloating are all potential signs that you could have too much Histamine floating around. It’s why some anti-reflux medications such as Ranitidine (Zantac) are antihistamines for the digestive tract!

The 4 main reasons Histamine issues occur

Medications, Genetics, certain medical conditions, the environment, nutritional deficiencies, and diet can all lead to a histamine intolerance. In clinic we tend to find there are 4 main reasons someone has developed this sensitivity and they are:


Your personal genetics could mean that you do not make enough Diamine Oxidase (or DAO) which is an enzyme in your digestive system that helps you break down the Histamine in the gut. Or you could perhaps have a reduced capacity of histamine-N-methyltransferase (or HNMT) which is another enzyme that breaks down Histamine within your cells. Both of these are not ‘fixable’ concerns as you are born with them, but you can definitely learn to support and work around them so you can live comfortably.

Bacterial Overproduction

Histamine is a very normal by-product produced by some of our digestive bacteria, and if you happen to have an overgrowth of these types, then you can become a bit of a Histamine factory! Correcting this gut imbalance is imperative to reducing your build-up of Histamine and allowing the gut to heal. This is something we specialise in with our clients.

Immune System Overdrive

Mast cells are the part of the Immune system that create Histamine and if they are overstimulated (maybe by a chronic allergen such as Dust or Cockroaches) and start producing (or degranulating) very large amounts of Histamine, then you can find yourself extra sensitive to any Histamine that is introduced into your body from your diet or gut function. Food allergies can also play into this area too.

High Histamine Consumption

Lastly, consuming a considerable excess of foods high in histamine can cause some issues, however this is not likely the cause and trigger. It is much easier to do than you think as Histamine is in everyday foods such as tomatoes, baby spinach, cheese, vinegar, fermented foods, avocado, chocolate, coffee, tea, alcohol (especially wine and champagne) bananas, citrus etc. The list is long but whilst we work with the diet initially to improve things, the goal is always to get you eating a variety of foods again.

Now in saying all this, true Histamine Intolerance from a Genetic standpoint is fairly rare, and we find that the most common culprits are usually from the bacteria in digestion and the diet.

Here’s what you can do about it

Taking an over-the-counter Antihistamine (such as Zyrtec or Claryintine) is the common course of action if your symptoms are obvious to you. This is a cheap and effective way to reduce the mass doses of Histamine your Immune System is producing in a quick manner. However, if this is something that you find yourself relying on and taking on an everyday basis, then you may be worsening the problem in the long term. Often stronger anti-histamines are required over time as their effects lessen. There is also a potential re-bound effect from dropping your whole blood Histamine levels so low after you take a strong medication such as an Antihistamine. Because the body requires a certain amount of Histamine at all times, the body can have a re-bound effect and start producing excess Histamine in response. Similar to what can happen when you scrub all the oils off your face too often – it can cause the skin to rebound by producing more oil as it detects excessive dryness.

Some natural options to try:

1. Taking some nutrients that assist with clearance of Histamine:

  • Vitamin C
  • Vitamin B1, Vitamin B2, Vitamin B6
  • Zinc
  • Quercetin

2. You can also try to temporarily reduce your intake of foods high in Histamine and see how you feel – you may notice a change within 1-2 weeks.

  • Vegetables: chilli, capsicum, eggplant, spinach, olives and tomatoes
  • Fruits: citrus, avocado, banana, strawberries
  • Cheese and Yoghurt
  • Nuts: walnuts and peanuts
  • Fermented alcoholic beverages, especially wine, champagne and beer
  • Fermented foods: sauerkraut, vinegar, soy sauce, kefir, yogurt, kombucha, etc
  • Vinegar-containing foods: pickles, mayonnaise, olives
  • Cured meats: bacon, salami, pepperoni, luncheon meats and hot dogs
  • Soured foods: sour cream, sour milk, buttermilk, soured bread, etc
  • Dried fruit
  • Smoked fish and certain species of fish: mackerel, mahi-mahi, tuna, anchovies, sardines

3. Speak to us about getting your gut sorted out (especially as this likely where the issue is coming from!) Gut health can be a tricky area as simply taking a probiotic may actually be contributing to the issue, not helping it! This is because some bacteria can secrete Histamine and some can help to break it down.

It is possible to correct your gut function and also assist with clearing Histamines on a daily basis so you may live a normal life. We have some great tools that we can use to help you enjoy your food (and the odd glass of wine). Many clients go on to no longer have to worry about excess Histamines in their body, but for those with stronger Genetic changes, we help them work around it so they can be as symptom free as possible without the use of medications.

Need some help?

Book Online with Naturopath Belinda or Monique today to get to the bottom of your issues.
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  1. Haas, H. S, 2008, Histamine in the Nervous System. Physiol Rev, 1183-1241.
  2. Maintz L1, Novak N, 2007, Histamine and histamine intolerance, Am J Clin Nutr, 1185-96.
  3. Kohn, J, 2014, Is There a Diet for Histamine Intolerance? J Acad Nutr Diet, 1860.
  4. Moulderings, G. B, 2011, Mast cell activation disease a concise practical guide for diagnostic workup and therapeutic options. Journal of Hematology & Oncology, 10.