What's all this about histamine?
If you, or someone you know, has had:
- hay fever
- a skin rash
- an allergy
- stomach acid problems
- Long Covid
... there may be a problem with HISTAMINE!
Anti-histamine medications are often used for these health issues. And the ‘low histamine diet’ has become newly popular as a way to combat Long Covid.
So what exactly is histamine, and why could reducing it be helpful?
Let’s introduce histamine. It may surprise you how closely it’s connected to many of the healthy foods we eat.
So first of all histamine is a ‘biogenic amine’ that's stored in our body’s mast cells and basophils, and released by a variety of triggers.
For example, pollen triggers the release of excess histamine in hay fever sufferers, and this in turn can produce skin redness, rashes and wheezing.
But histamine is present almost everywhere in the body and it’s ‘pleiotropic’, which means it has a LOT of different, seemingly disconnected roles.
These different roles relate to the four different receptors for histamine in the body and will relate to different health issues.
Some typical health issues connected with histamine:
H1 receptor – allergy reactions, both skin reactions and airway problems
H2 receptor – secretion of stomach acid, intestinal motility (how well you digest food).
H3 receptor – neurotransmission: energy, sleep/wake cycle, neurology eg migraine, moods
H4 receptor – immuno-modulation: allergic rhinitis, immunity, osteo/rheumatoid arthritis
It’s important to remember, though, that the normal function of histamine shouldn’t produce unpleasant reactions.
Ideally, histamine would simply operate as a part of the healthy inflammation process, like wound healing, and support healthy ‘homeostasis’, or balancing, in the body.
It's when histamine levels become excessive that when symptoms appear.
But we still need to bear in mind:
Histamine excess affects everyone in a unique way.
I am quite sensitive to histamine and my face has always flushed easily.
Just other day I was frankly informed that when I laugh a lot, I look like a strawberry!
But on the other hand, I don’t get hay fever or asthma. It all depends on which of your receptors are affected and where they are in the body.
For example, not long ago I was flummoxed by the case of a young girl under 10 with problematically frequent loose stools, alongside occasionally itchy skin, and a slight tendency to be over-excitable.
I looked at food intolerances for a while, but then realised that histamine, being an excitatory neurotransmitter, was causing overactivity in this girl's skin, gut and mood. For her, addressing histamine proved to be a game-changer, and her loose stools resolved.
So how is it that one could become overloaded with histamine and get unpleasant reactions?
Histamine can become excessive in the body for many reasons, and this is sometimes called ‘histamine intolerance’.
Histamine intolerance essentially means:
1. Too much histamine in the body OR
2. Too little ability to degrade histamine OR
Here are some of the key practical ways that histamine can become raised:
A. Certain food and drink can encourage high levels
B. Certain gut bacteria and parasites can produce high levels
C. Genetics that cause less effective histamine-degrading enzymes
D. Environmental toxins which trigger inflammation.
Perhaps the most easily manipulable factor in that list is the first one, food and drink.
So let’s look at this.
Foods and drinks which can affect our histamine levels
Foods and drinks may:
1. Contain actual histamine
2. Contain other ‘amine’ foods that impact us similarly to histamine
3. Liberate histamine within our body
4. Inhibit the enzyme Diamine Oxidase (DAO) which breaks down histamine
5. Affect intestinal permeability
Here are some foods and drinks in these categories:
1. Foods which contain high levels of histamine
Histamine forms when food is fermented, preserved, matured or ripened. Annoying, if we have been faithfully consuming fermented foods for our gut health!
Histamine will be high in:
- Fish that’s not freshly caught - Cured meats eg ham, sausages, salamis - Matured / processed cheese - Yoghurt - Fermented drinks, e.g. kombucha, kefir - Alcoholic drinks - Vinegar - Pickled vegetables - Soy/tamari sauce - Worcestershire sauce - Yeast extract
Histamine is also naturally high in certain fruit and vegetables, including tomatoes, spinach, aubergine and avocado. 2. Foods which contain other ‘amines’ These high ‘amine’ foods compete with histamine to be broken down by the histamine-degrading Diamine Oxidase or DAO enzyme, and may therefore raise histamine levels in the body:
- Pineapple - Banana - Pears - Peanuts - Raspberries - Legumes (lentils, beans, soy products) - Kiwi - Oranges, Grapefruit - Papaya - Wheat germ
3. Foods which liberate histamine within the body These foods encourage the body’s own histamine-containing cells (eg mast cells) to release their histamine:
- Alcohol - Strawberries - Nuts (walnut, cashews) - Seafood / shellfish - Chocolate, cocoa - Tomatoes, ketchup, tomato juice - Citrus fruits
4. Foods which inhibit DAO
These foods inhibit the histamine-degrading enzyme Diamine Oxidase, or DAO, that would otherwise reduce histamine levels:
- Cocoa, chocolate
- Mate tea
- Black tea
5. Foods which may increase intestinal permeability
These may cause a greater exposure to histamine, or reduce its breakdown in the gut:
- Any foods to which you’re already intolerant
- Spicy foods
- Sugary foods (which encourage less-beneficial bacteria)
So, what to do about food and drink: the ‘histamine bucket’
You may be wondering, ‘goodness, do I have to cut out ALL those foods FOREVER if I’m going to get rid of my hay fever or other symptoms?’
Well, the answer (as always) will depend on your unique health picture. And individualised advice is usually sensible if you have a long-term problem.
But for now, a useful way to think of managing food and drink is to imagine a ‘histamine bucket’.
You want to keep your ‘histamine bucket’ from overflowing, so you simply bear in mind what you’re eating on that particular day, and try not to let things add up too much.
The level you can tolerate will be unique to you.
For example, if in one day you have:
- an avocado and spinach smoothie for breakfast
- cheese and tomatoes at lunch
- soy sauce added to dinner
… you may raise your histamine levels too high for comfort.
But you might be able to spread these same foods across a few days and not experience symptoms.
Some people may be most triggered by histamine-containing foods like preserved meat.
Others may find that simply avoiding something like alcohol removes their sensitivity.
With a little observation, you may identify your particular ‘trigger foods’ and so reduce your symptoms. You might need to reduce those foods, or avoid them for a while. And perhaps slowly reintroduce them, later.
It’s important to know that our reactions to histamine will be entirely individual, and that they’ll be affected not just by food intake, but also by factors like gut bacteria and household toxins.
For example, identifying and removing a gut parasite may mean that your histamine reactivity to foods will reduce considerably.
We’ll look at all these other factors in more detail in another blog, together with the key nutrients which support calmer histamine levels.
For now, I hope this was a helpful introduction to histamine, and that you, or someone you know, will benefit.
As always, feel free to get in touch with any questions or comments, or to see if nutritional therapy could help you.
To your very best of health,
Clare Backhouse, dipION, Registered Nutritionist MBANT
Registered Nutritional Therapist CNHC
References and resources
For other references, see:
Afrin, L.B., Weinstock, L.B., Molderings, G.J., 2020. Covid-19 hyperinflammation and post-Covid-19 illness may be rooted in mast cell activation syndrome. International Journal of Infectious Diseases 100, 327–332.
Branco, A.C.C.C., Yoshikawa, F.S.Y., Pietrobon, A.J., Sato, M.N., 2018. Role of Histamine in Modulating the Immune Response and Inflammation. Mediators of Inflammation 2018.
Busse, W.W., Knuffman, J.E., 2006. HISTAMINE, in: Laurent, G.J., Shapiro, S.D. (Eds.), Encyclopedia of Respiratory Medicine. Academic Press, Oxford, pp. 279–283.
Deiteren, A, De Man, J.G., Pelckmans, P.A., De Winter, B.Y., 2015. Histamine H4 receptors in the gastrointestinal tract. Br J Pharmacol 172, 1165–1178.
Magen, E., Mishal, J., 2013. Possible benefit from treatment of Helicobacter pylori in antihistamine-resistant chronic urticaria. Clinical and Experimental Dermatology 38, 7–12.
Maintz, L., Novak, N., 2007. Histamine and histamine intolerance. The American Journal of Clinical Nutrition 85, 1185–1196.
Mehta, P., Miszta, P., Rzodkiewicz, P., Michalak, O., Krzeczyński, P., Filipek, S., 2020. Enigmatic Histamine Receptor H4 for Potential Treatment of Multiple Inflammatory, Autoimmune, and Related Diseases. Life (Basel) 10, 50.
Nuutinen, S., Panula, P., 2010. Histamine in Neurotransmission and Brain Diseases, in: Thurmond, R.L. (Ed.), Histamine in Inflammation, Advances in Experimental Medicine and Biology. Springer US, Boston, MA, pp. 95–107.
Smolinska, S., Jutel, M., Crameri, R., O’Mahony, L., 2014. Histamine and gut mucosal immune regulation. Allergy 69, 273–281.
Thangam, E.B., Jemima, E.A., Singh, H., Baig, M.S., Khan, M., Mathias, C.B., Church, M.K., Saluja, R., 2018. The Role of Histamine and Histamine Receptors in Mast Cell-Mediated Allergy and Inflammation: The Hunt for New Therapeutic Targets. Front. Immunol.