Tag Archives: DAO

There are none so blind..

…as those who don’t wish to see.

Y’know as a kid when you didn’t want to hear something you’d stick your fingers in your ears and go “la la la la, can’t hear you!”  I’m starting to think that’s the way most people feel about histamine.  They only hear the bits they want to hear and ignore everything else.

To me, the most important page on my entire blog is the one about the evidence of Histamine in foods, yet it receives the least visitors and has no comments.  Not a single one.   The article proves that there is basically zero evidence on which to base any of the current Low Histamine Food lists and that the histamine content in food is just a guess, and oftentimes not even an educated guess.  It’s very important to know this, particularly if you have HIT and could go into anaphylaxis if you eat too much histamine-rich food.  But it seems no-one cares.  No-one is shocked at the lack of evidence for histamine in food.  And that shocks me more than anything!

In comparison, The Low Histamine Food list page has the most traffic, even though I’ve proven it’s not based on fact or much of anything else.  It seems no-one’s bothered how accurate, or not, the low histamine food lists online are despite the fact their lives could depend on it.

We see what we want to see, especially when we’re desperate.  We see a list of research references at the end of an article and think to ourselves “oh well, it must be based on fact then”, even though we don’t bother to read the research references to find out how old they are, how big the study was, if it was replicated, if it appeared in a peer review journal and was scrutinized.  In other words, whether the research the article is based on is just a theory or whether it’s fact.

All the low histamine diets online tell you should avoid egg white.  Did you know this is based on one single miniscule study done in the 1950s on mice which was never published or scrutinized?   Would you let someone operate on your heart, based on a single research study on mice done just after the Second World War?  No, I thought not.

No food is innately high in histamine.  Histamine is produced during the aging process (eg mature cheese), the production process (eg. yoghurt, vinegar) or during storage and transportation.  The latter is very important.  A banana straight off the tree will be zero histamine.  A month old, brown, soggy banana will be high histamine.  Our food storage and transportation has come on leaps and bounds in the last 60 years.  We now use refridgerated lorries and food often appears in supermarkets within days of being picked or produced which impacts its histamine level.

I wish if nothing else people would take away from my blog the fact that there is no such thing as a Low Histamine Food list.  They don’t exist.  It’s pointless Googling for whether or not Pak Choi is low or high in histamine, cos no-one knows.  No-one knows whether the blackberries I pick off the bush in my garden contain histamine, or are higher in histamine than the blackberries shipped in from Israel for sale in the supermarket.

No-one knows how food affects DAO in the gut.  We can’t even accurately measure DAO in the gut, so how on earth would we know if any food increases or decreases it?  No-one knows if particular foods (eg. lemons) releases histamine stored in mast cells.  And if you read differently online the person or company saying otherwise is either lying, guessing or simply hasn’t done their homework properly.

I know what I’m saying is deeply unpopular.  I know sick people don’t want to hear it.  But we should all know the facts about this stuff.  It’s important.  People following low histamine diets are cutting out all sorts of foods for absolutely no good reason.  Aren’t our lives hard enough without that?  If you don’t believe my research, do your own.  Try and find evidence for the histamine content in foods – real evidence.  Properly conducted up-to-date research published in medical or food Journals.  And you’ll find it’s virtually non-existent.  Just because there’s an app listing foods high in histamine doesn’t mean it’s accurate for heaven’s sake!  And any app which lists foods which liberate histamine from mast cells, or which increases or decreases DAO is wrong, wrong wrong!  Ask the people who produce the app to provide you with the evidence on which they base their information.

Knowing all this, I’ve been re-introducing some foods back into my life which I’ve avoided for the past 3 years.  There is no evidence for baker’s yeast being high in histamine, and I really miss proper bread especially when I’m out and about, so I’ve been eating it in small amounts for a few months now.  I still have my yeast-free bread when at home because I like it, it’s organic and doesn’t contain any of the crap of supermarket bread, however it’s only nice toasted so when out of the house I eat ‘normal’ bread in cafes and for my sanis.  I’m happy to report no effects on my symptoms whatsoever.  None.  Yayyy 🙂

I’ve also re-introduced milk chocolate.  I’m careful to use brands without soya of any kind (one of the only foods for which there is proper evidence of high histamine content) and am again happy to report that it has not affected me one iota.  My hormones are ever so grateful – having a menstrual period without chocolate was sheer hell 😉

There is not a shred of evidence for the histamine content of fruit or how fruit affects histamine in the body.  Not lemons, not oranges, not strawberries.  No research has been done on it.  So over the summer I intend to try various fruits I’ve been avoiding, one by one, and see how it goes.  Bananas are not purported to be high in histamine, yet they make me brain fogged, so it may be I react badly to some fruits for reasons no-one understands and which has nothing to do with histamine.  Or bananas may be high in histamine.  No-one knows, as they’ve not been tested!

Please, think about what you read online.  Just because 100 people are saying one thing, and 1 person is saying the opposite, doesn’t mean the 1 person is wrong.  Do your homework.  Look at the evidence and make informed choices.

HIT: DAO & Peashoots

Along with Mast Cell Activation Disorder I have the double whammy of also suffering from Histamine Intolerance.  Many people confuse the two, but they are distinct diseases with different causes and need different treatments.  Histamine Intolerance (HIT) is caused by a lack of enzymes in the stomach, one of which is Diamine Oxidase (or DAO).  There are other enzymes involved but DAO is the only one we currently know much about.

All the food we consume contains histamine, but some foods are much higher in histamine than others.  When we eat our stomach also produces histamine to aid digestion.  DAO then mops up any histamine left over from the digestive process.  For those low in DAO, however, this excess histamine isn’t dealt with and results in histamine toxicity with all sorts of unpleasant symptoms.

We don’t really know, as yet, what causes DAO deficiency.  It’s thought that some people may be genetically low in the enzyme, while other people may acquire DAO deficiency through taking certain medications.  I’m not sure where I fit in in these hypotheses.  I haven’t taken drugs for years due to my MCAD reactions, and until I was in my mid-forties could eat anything I liked without any kind of reaction so if I’d been born with low DAO this surely would have shown itself earlier.  So my guess is that there are other factors at play which can affect DAO of which we are currently unaware.

It’s obvious why following a low histamine diet helps in HIT – the less  histamine we eat the less our stomach has to deal with and the less histamine is floating around our bodies causing havoc.  There are supplements on the market, eg. DAOSIN, which claim to increase DAO.  My Consultant, when asked, didn’t dismiss these entirely but did say that he doesn’t endorse them as there is no evidence on their efficacy or safety.  It’s up to the individual, therefore, whether they want to use supplements without really knowing how they work or if they have any negative side effects.

There is an International DAO Society made up of researchers who study DAO and their research has found that DAO is abundant in young pea shoots.  You can buy these from the supermarket, though they do degrade quickly and look a bit like a limp rag by the time you get them home, or you can grow your own.  It’s cheap, easy and a lot quicker than you might think.

1. Buy a bag of dried marrowfat peas from the supermarket.

Photo of dried marrowfat peas

2. Soak the dried peas in water for 24 hours (the amount will depend on the size of crop you want, but it might be best to do a large handful every few days then you’ll have a continuous crop rather than having them sprout all at once).

Photo of dried peas soaking in water

3. Select a shallow container, about 2-3″ (6-9cm) deep – seed trays are ideal, or you can use a wooden box so long as you put drainage holes in the bottom.

4. Fill the container with compost, multi-purpose is fine.

5. Water the compost, then just lay the soaked peas on top.  You can sow them close together, just any old how is fine.

Photo of sowing peas in a tray

6. Cover with a layer of compost, about the depth of one pea and water again lightly.

7. You can grow peashoots both indoors or outdoors.  Research suggests that growing in the dark for the first few days can increase the DAO produced by the peas, but I just grow mine in the kitchen windowsill.  They start to germinate literally within 24 hours.

Photo of germinated pea shoots

8. Keep the compost moist but not wet and within 2 weeks your shoots will be about 3-4″ high and ready to harvest.  Chop off the shoots above the first set of leaves.  Some of the shoots will then re-grow and give you a second crop.

Photo of peashoots ready to harvest

You can add peashoots to smoothies, or salads, include in sandwiches or use as a garnish.

Apologies for any typos in this post and my poor grammar – I’m trying to write on an empty stomach and through a pounding spacey migraine!


My Diagnosis

Today was D Day and my appointment in London with Dr Seneviratne regarding my diagnosis.  As I type I am on a rickety tilting train (which is making me feel really motion sick) travelling the 300 miles home north only 7 hours after I began the journey south.  I am beyond tired, my brain is mush, my back is killing me and I have painful reflux but I also now have a diagnosis (fanfare please!):


Yes my friends I have the double whammy!

My DAO came back low at 7 (anything below 10 indicates histamine intolerance, with most people’s being at least 20).

My N-methylhistamine came back normal, but at the high end of normal at 140 (range is 34-177).  However, this has to be balanced with the fact I had been on a low histamine diet, and actively restricting histamine intake, for 8 months before I had the tests done in addition to taking anti-histamines.  Bearing this in mind I really shouldn’t have had a histamine level that high, and both Dr S and I are convinced that if I hadn’t been on the low histamine diet my N-methylhistamine would have been through the roof.  In a way it’s a shame I didn’t have the tests done this time last year, when my reactions were terrible and I hadn’t started the diet or any drugs.  However, the fact that it’s still high even with the diet and drugs proves to me that last year it would have been off the Richter Scale.

The diagnosis of Histamine Intolerance is absolute.

The diagnosis of MCAD is “probable” simply because the histamine tests were within the normal range, but like I said he is taking my diet into account and still giving a “probable” MCAD diagnosis based on history and symptoms.  We both agreed it is incredibly frustrating not to have access to PD2, heparin and the other tests available in the States which would have proved beyond doubt that I had MCAD.  I know Dr S is trying hard to get these tests made available through The Doctor’s Lab and for them to be available in the north of England (The Doctor’s Lab has a branch in Manchester) not just London.  It would be a huge stride forward in mast cell disease diagnosis in the UK.  I could stop the anti-histamines and the diet, wait 6 months and then have the tests repeated but I’m not desperate enough for an “absolute” MCAD diagnosis to want to start passing out again every time I eat – a “probable” is good enough for me.

It’s been a lonnnnng road.  I’ve had symptoms like flushing and dermographism since early childhood, raging drug reactions for 15 years, GERD for 10 years, and ‘allergy’ type symptoms and food reactions for 2 years.  I have been told my drug reactions were “behavioural”, or a “panic attack” or I was looked at like I was totally nuts.  I feel so grateful to finally have vindication that, no, I was in fact having an anaphylactic reaction and my body was being flooded with potentially life-threatening histamine.

My S wants to try me on Sodium Chromoglycate (a mast cell stabilizer) and see how it goes (if I can tolerate it, and it’s a big if).  Despite my DAO being very low he doesn’t advise taking DAO supplements as he doesn’t know enough about them to know if they’re either effective or safe in the long-term.  I’ve got to say I agree with him.  Just because something is a “supplement” rather than an actual drug it’s often thought that it must be safe and innocuous.  Trust me, it’s not.  I’ve had two of the worst mast cell reactions of my life to supplements I bought from a health shop, one of which was Melatonin to supposedly help me sleep.

The other thing that came out of the consultation today is that Dr S wants me to be referred to the Syncope Clinic at Newcastle run by Julia Newton.  Thankfully this is an NHS Clinic and considered one of the best in the country to diagnose and treat Dysautonomia.  I’ve had Dysautonomia for 20 years but have never had it formally evaluated simply because I know they’re going to offer me drugs I won’t be able to tolerate and, pre-mast cell diagnosis, when I refused drugs I was often told by medical professionals that I was wasting their time and obviously didn’t want to get well!  Now I’m hoping medical staff will take my drug issues a bit more seriously even if my weird reactions don’t appear in some dusty old medical textbook (I may subtlely remind them that if they are aware I have drug allergies, don’t take them into account and I have anaphylaxis, I could sue).

It’s now past midnight, I’ve just arrived home and I’m really ready for some sleep.  I go back to see Dr S in 4 months for a follow-up.  Please ignore any typos, as my last remaining brain cell gave up the ghost somewhere around Preston 😉


Following my appointment with Dr Seneviratne on Tuesday, I’m now waiting to have some tests carried out to determine my histamine load.  Luckily I’d already had many allergy-type tests done (skin prick for allergens, total IgE, tryptase, inflammatory markers, routine blood work like cell counts etc.) when I had my NHS Immunology appointment at Preston in June and my GP had sent copies of the results to Dr S with my referral letter, so these didn’t have to be repeated.  I’ve also already had an endoscopy and been tested for Coeliac Disease and H-Pylori infection (both were negative) and a full abdominal MRI scan (also clear).

Dr S explained that he no longer recommends a 24 hour N-methlyhistamine urine test, as he found this could not be standardized and therefore results were unreliable.  Instead he now orders a spot urine test, in which the histamine:creatinine ratio is measured.  This is a very specialized test, in which the urine has to be immediately frozen to preserve histamine, and currently only available at The Doctor’s Laboratory in London (a private lab which can only be used by medical staff).  There is, however, a branch of The Doctor’s Lab in Manchester, which would be much easier and closer to home for me, so he is in the process of enquiring if they have the equipment and knowledge to do the test there, but did explain that if there was any doubt I’m better travelling all the way to London as at least then I’m guaranteed a reliable result.

The second test he’s ordered is for DAO.  I was unaware that this was available in the UK, so am extremely pleased it can be done here.  This test measures levels of Diamine Oxidase, a stomach enzyme which breaks down the histamine present in the foods that we eat. Low DAO indicates Histamine Intolerance (HIT).  Having been on a low histamine diet now for 6 months I’d be surprised if there was a problem with my DAO levels, but you never know and it will be interesting to see the results.

I was hoping to start trying a Vitamin C supplement next week, as although the H2 antihistamines I’m currently taking for my stomach acid stop histamine binding to mast cells they don’t deal with the histamine itself, which continues to float around in the body causing symptoms.  Vitamin C actually destroys histamine (one molecule of Vitamin C destroys one molecule of histamine), although it does have to be taken in high, divided doses throughout the day as it’s very quickly excreted through urine.  However, Dr S has advised I take no more drugs or supplements until I’ve had all my tests done.  I forgot to ask him if I should continue on a low histamine diet, or maybe stop it a week before the tests are due – I’ll have to email his PA to ask.

I admitted to Dr S my worst fear is that the tests will come back fine (in 20 years of being incredibly ill, I have never ever had a test come back abnormal, even when I was told I was critically ill and might not make it through the night).  However, he reassured me that my history and symptoms all point very definitely towards MCAD and that if the tests came back fine I simply need them repeating when I’m more symptomatic, or at regular intervals until we catch the histamine (I’d probably aim for spring, when the pollen season begins and I usually have a good 2 months of hives).  Watch this space!

I’m feeling pretty nauseous with the stress and fatigue of the past week, so am drinking copious amounts of fresh ginger tea (a natural anti-histamine and anti-emetic).  See the Miscellaneous section of the Recipe Page for details and scroll down.

Photo of ginger tea