Today’s post couldn’t come at a better (or worse) time, as we’re going to discuss histamine. It seems so utterly unfair that there essentially exists an allergy to summer, hay fever! One in 4 people in the UK suffers from hay fever, and it can be utterly debilitating.
When we have hay fever, histamine is secreted from our mast cells (antihistamines stop this happening), but histamine is actually not the issue, it’s our immune system not recognising that pollen isn’t a life threatening immune challenge. However, for some of us, our immune systems get confused and mount a reaction to the pollen molecules, histamine is released from the mast cells, and we get itchy, blocked nose, swollen eyes etc as our bodies try to flush out the pollen.
So, let’s look at histamine with the help of Nutritional Therapist, Grace Kingswell.
If you suffer from itchy skin, hives, urticaria, angioedema or any kind of sudden flare up then it’s highly likely that histamine is responsible for ‘the itch,’ in which case I’m sure you’ll find this post useful!
Histamine is not just about hay fever, though most of us will only know the term in relation to that. You may be surprised to find out that it is also present in all our food, with some foods having higher histamine levels than others.
Histamine isn’t all bad though...it’s an important neurotransmitter and has a key role to play in wellbeing.
The issue is once histamine is secreted it has to be detoxified out, and if that route out isn't working and we’re also taking in huge amounts via our diet or because of pollen, then the histamine bucket overflows and we get reactions on the skin, in the lungs and systemically to - brain fog, fatigue etc.
Apart from pollen, where else does histamine come from?
So we know that food contains histamine, and we know that we need antihistamines if we’re having an allergic reaction, but let’s look at some of the other sources of histamine:
- Gut dysbiosis: some strains of bacteria in the gut produce histidine decarboxylase (the precursor to histamine). Studies have shown that histamine secreting microbes are present within the gut microbiota, and that their levels are higher in asthma patients (and I would also add here that this is likely true of hayfever patients too).
- Food (already mentioned) and some of the highest histamine containing foods are: bananas, spinach, strawberries, peanuts, preserved or fermented foods, alcohol (if you suddenly have a stuffy or runny nose after a glass of wine, that’s a histamine reaction) and anything that’s been stored or cooked for a long time e.g. canned food.
- Hormones: Histamine can stimulate oestrogen production! Oestrogen induces mast cell degranulation (i.e. histamine release) in female reproductive tissues and elevated oestrogen levels during the menstrual cycle therefore induce histamine release. Are you more reactive before or during your period? Does your skin get itchy? Do you experience food ‘intolerances’ around this time of the month?
- Inflammation: The inflammatory cytokine storm (side note, but you might have heard that terminology in relation to Covid over the last year - essentially an inflammatory response is a cytokine cascade or ‘storm’) produces histamine. So more inflammation generally equals more histamine. So if you have any kind of inflammation from joint pain, skin issues etc then you’re likely to also have elevated histamine levels too.
- Some medications also induce histamine, and then there is of course MCAS - Mast Cell Activation Syndrome, a topic for another time!
So what does histamine do?
It modulates the immune response and inflammatory response (so it’s actually super important!) and it does this via 4 receptors, i.e. it gets secreted and then activates 4 receptors in the body called HR1, HR2, HR3 and HR4. Essentially this means that it’s a vital part of our immune system and the way our bodies deal with inflammation.
So what is histamine intolerance and what can you do about it?
Essentially, it’s the imbalance between accumulated histamine and histamine degradation - i.e. it’s breakdown and detoxification and removal from the body. Essentially the body can’t get rid of the histamine fast enough.
The removal of histamine from the body is largely dependent on an enzyme called DAO, which you can take in supplement form, or dependent on another process called HNMT (Histmaine-N-Methyltransferase).
So if you were consuming huge amounts of histamine in the diet, for example, you could try taking a DAO supplement, but as I mentioned earlier - hay fever is a case of the immune system not recognising pollen as “non-threatening,” and the only way to improve that is to support your immune system over all: gut health, sleep, diet, stress, immune-necessary-nutrients like Vitamin D, and so on.
So what do you do?
It’s a complicated topic, as you can see, but if you’re keen to get to the bottom of it then ideally work with a practitioner. If you want a quick reduction of symptoms then you can follow a low histamine diet, and actually I would recommend this for hayfever sufferers for the summer, as it just takes some of the histamine pressure off.
Ultimately you’ve got to figure out why your histamine bucket is overflowing: is it stress, is it genetics, is it methylation and detox, is it low DAO enzymes, is it oestrogen and hormones, is it your circadian clock being out of balance? It’s a complicated picture!
Remember that all of the lifestyle factors WILL help, (and always do help in every health scenario): following an anti-inflammatory diet, getting lots of sleep and rest, getting as much daylight and sunshine as you can, reducing toxicity, reducing stress.
Hopefully that provided you all with a much deeper understanding of histamine, what it does in the body, and how to deal with it. And, if you’re after that anti-inflammatory diet, you know where to head: our new deli at Triyoga 372 Kings Road in London!