When you hear the word histamine, drugs like Benadryl probably come to mind. It’s common to use antihistamines in the face so strong allergic reactions.
If histamine hasn’t given you much trouble other than a few runny noses in the spring, you probably haven’t given it as much thought.
On the other hand, if you suffer from severe allergies, histamine intolerance, mast cell activation syndrome (MCAS) or any other condition that causes your histamine levels to be higher or your body to less tolerant – then you know firsthand how powerfully histamine can rule over your life.
With chronic illness on the rise, I’m seeing higher incidences of histamine intolerance and mast cell activation syndrome in my practice. Though these conditions can have overwhelming symptoms, there’s a lot that can be done to keep them in check.
First, let’s take a step back and understand three critical concepts:
- How histamine affects the body.
- What you can do to reduce the impact of histamine over your life.
- How to boost DAO enzyme levels, which is responsible for breaking histamine down.
What is Histamine?
Histamine is an important part of your immune system because it causes necessary inflammation during times of injury and healing. Histamine is released from your mast cells, which are present in every tissue in your body. Mast cells release multiple chemical inflammatory mediators as part of your immune system response. Histamine is only one of these hundreds of chemicals your mast cells can release – though it gets a lot of attention.
Histamine is incredibly powerful. For example, in the case of someone who’s severely allergic to peanuts, the smallest taste can trigger a strong histamine response. When histamine is unleashed, it sends inflammatory signals throughout your body – to your gut, nose, throat, mouth, skin, and lungs. Histamine is the chemical that’s largely responsible for the trademark allergic reaction.
When histamine runs rampant and unchecked, it can cause health complications like histamine intolerance and mast cell activation syndrome. A buildup in the body can happen because of excess histamine but also insufficient DAO levels.
If you want more on the effects of histamine, you can read more in my article, Mast Cell Activation Syndrome: When Histamine Goes Haywire.
The Mighty DAO Enzyme
Diamine oxidase (DAO) is an enzyme that’s responsible for breaking down histamine. Another enzyme responsible for breaking histamine down is called histamine N-methyltransferase (HNMH), but we are going to mostly focus on DAO because it’s much more effective.
DAO is mostly found in the kidneys and thymus. In pregnant women, DAO levels rise significantly and are found in the placenta. In the body, DAO breaks down histamine, which is then excreted through your kidneys and urine.
DAO is also found in the small intestine, in two sections called the jejunum and ileum. When foods high in histamine pass by this part of the small intestine, DAO breaks it down and prevents it from entering the body. When you have sufficient DAO, nearly all of the histamine that passes through your digestive tract is broken down and therefore doesn’t cause any issues.
If you don’t have enough DAO, it can cause histamine levels to rise. If this goes on long enough, it can cause histamine sensitivity, chronic inflammation or mast cell activation syndrome.
If you suspect you have too much histamine or not enough DAO enzyme there are a couple of things you can do:
- Reduce the histamine in your diet
- Boost DAO enzyme
- Avoiding DAO blocking foods
In general, avoiding histamine means avoiding old or aged food. This includes vinegar, alcohol, cured meats, smoked meats, fermented foods, canned foods, and leftovers. However, this is just a general rule of thumb and there are other foods that contain histamine.
There’s a lot of helpful information online about low histamine diets. One of my favorite resources for this is Healing Histamine. There you can find extensive food lists that show you how to reduce your histamine intake, which is very effective overall.
I want to more talk about boosting your DAO enzyme levels, let’s take a closer look.
Boosting Your DAO Enzyme Levels
You can take DAO supplements, which will increase your levels in your digestive tract and enhance histamine breakdown of anything that’s eaten. However, DAO supplements do not get into your bloodstream and cannot increase your DAO levels internally. This means that supplementing with the DAO enzyme only helps you break histamine down that you’re consuming.
DAO enzyme supplements will not break down histamine that’s created by your mast cells – though this is still an effective treatment. This also means that DAO supplements cannot cure histamine intolerance or mast cell activation syndrome, they are not a histamine intolerance treatment. Now you’re probably wondering how we can boost DAO naturally and how to reduce histamine in the body.
Scientists have found a number of nutrients that are effective at boosting DAO enzyme levels. These nutrients include:
- Omega-3 fatty acids
- Saturated fat
- Vitamin B12
Foods that boost the nutrients listed above
Foods that help boost nutrients which may increase DAO levels in your body include:
Omega-3 is an important one, they have been shown to release DAO and in women. Eat more:
- Olive oil
- Wild caught salmon
*Be wary of fish oil supplements, which are very susceptible to oxidation.
Healthy saturated fats:
- Grass-fed butter
- Fatty fresh fish
- Pasture-raised chicken eggs (unless it’s a sensitivity)
- White beans
- Pasture-raised chicken eggs (unless it’s a sensitivity)
- Dark leafy greens
- Grass-fed meat
- Dark leafy greens
- Grass-fed beef liver
- Grass-fed beef
- Wild caught salmon
- Fresh tuna
- Pumpkin seeds
- Grass-fed beef
Avoiding DAO Blocking Foods
If you’re having trouble with histamine, the number one thing you should avoid is alcohol. Histamine and alcohol share metabolic pathways that use the enzymes, aldehyde dehydrogenase and aldehyde oxidase.
Alcohol always releases histamine from your mast cells but if you develop to histamine sensitivity, this reaction become more prominent. You’ve probably seen this reaction before, it’s what makes a person’s face become flushed from drinking too much. Not only does alcohol release histamine, it also blocks to DAO. This histamine release in response to alcohol can get worse and worse.
The available information on histamine related issues has exploded in just the last two to three years. We are learning a lot more about histamine and DAO at a fast rate and this will only continue to get better.
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* These statements have not been evaluated by the Food and Drug Administration. The product mentioned in this article are not intended to diagnose, treat, cure, or prevent any disease. The information in this article is not intended to replace any recommendations or relationship with your physician. Please review references sited at end of article for scientific support of any claims made.
Thank you so much for the list of foods that help with DAO production. I’m confused, though. Avocados and spinach are on all the lists as very high in histamines, yet they are on your list for DAO producing foods. I’ve been avoiding them along with quite a few others, like strawberries. Should I be trying to slip avocado in when I think my bucket is low?
If you are sensitive to histamine, you may need to use caution with high histamine foods
what? your comment does not address joanna’s question, which is also my question. isn’t your whole article about histamine sensitivity? the question is about the foods you list in which categories. in general, i am finding different functional docs list same foods in opposite categories. this is very confusing!
No, this article is exclusively about DAO levels and what foods may increase DAO. It says nothing about high histamine or foods that contain high histamine, nor should it be read as such – you can read more about MCAS and histamine here
I feel I cannot trust my understanding of your article. Your title is Boost DAO to Fight Histamine, yet you list foods that are high in histamine to get DAO. I dont understand the logic of trying to fight histamine with DAO foods that are high in histamine.
There are many sources of histamine. Not all are from the diet and you can still fight endogenous histamine with foods that may boost DAO. There is no one size fits all nor are all foods containing histamine a problem with those who have more trouble with DAO enzyme production.
I heard that you should try some of the foods that are known to be high in histamine because everything on the list may not bother you. Like in my case I cannot tolerate wine, kimchi and the verdict is out on cultured vegetables. In some of my research I’ve read that it can build up in your system over time making it hard to pinpoint exactly what is causing the flare up. Not knowing what my problem was for more than a year my chiropractor took me off of everything except vegetables, meat and certain oils. All of my symptoms went away until I started introducing some fermented foods and unfortunately wine. Strawberries and avocados don’t bother me.
But…. having cut wine out for such a time it took a while before it caught up to me. Having said this I think that if I had of drank a glass from time to time it would have been okay.
I also believe that the makers of these new and cheap wines are adding something to their ingredients that is aggravating the system more so than ever.
Sulfates in wine really aggravates my symptoms. There is one brand
“Our Daily Red” that is sulfate free.
I was thrilled to find out when I actually looked up the mg that avocado only has 23mg/kg of histamine. https://optinghealth.com/foods-high-in-histamine/ I have NO CLUE why it’s on the list since others, anchovies- 1,250 mg/kg and Swiss cheese -2,500 mg/kg have far higher levels. Eggplant is on the list though it only has 26 mg/kg. Saurkraut has 229 mg/kg,and yogurt has 13 mg/kg and miso has 3 to 6 mg/kg. Sour cream has up to 7 mg/kg and buttermilk contains 87.4 mg/kg. It doesn’t tell us what number of histamine is “low”. I think I’ll take my chances on yogurt and milk, and sour cream. And avocado.
Great summary, thank you!
Hello ! I read your “DAO Boosting Foods” list,,,And I see some items you have listed, that are on other lists by other people that are said to contain high histamine levels. These food items are, ALL NUTS, SPINACH and AVOCADO. BUT, you have them listed on your “DAO Boosting Foods” list as a boost to your DAO levels… So,,, how can these foods boost DAO, if other people have listed them as high histamine food items ??? I don’t get it ! Please respond, Thank You Very Much !! R. J. Hafer Benton Harbor, Michigan 09-20-2018
Yes i would like to hear a response to this too!!! thanks
Also wondering the same thing over here…some foods are on both lists and contradicting? Very confused
PS Hello again,,, It would be nice if ALL the food industries would list the HISTAMINE CONTENT of their product on their food container labels. It should be law…R. J. Hafer Benton Harbor, Michigan 09-20-2018
The food industry conned voters to vote NO on listing Glyphosate on labels. I doubt very much they would list histamine without a fight. Also, histamine levels change by the moment, as leftover foods develop histamines the longer they are leftover. They have no way of measuring that.
I have read that Coq10 supplements can help histamine issues, but I have also read that they can make it worse due to the fermentation process to make the supplements? What about ubiquinol? Any certain brand of these if they ARE helpful? Also, how to test for histamine and DAO issues? Thank you
Any product or food from fermentation should be avoided if you have mast cell issues
If you have mast cell issues as well as Sifo ,Sibo and Candida that has resulted in leaky gut and compromised biome needing probiotic replacement and intestinal lining repair what is the balance. Candida has biproduct of grain alcohol which can release histines apparently. It seems like one hand slaps the other. I have had extreme chronic inflammation and histine symptoms as well. The foods that treat one issue exasperates the other. Not sure what to do. I am also dealing with mold recovery.
I have MCAS and while these articles are helpful, 50% of the foods you list I cannot eat so it’s dissapointing to read something that seems good and then I get to the bottom and have to disregard almost all of what is said. While every person with histamine issues have different tolerances, it sure would be great for health practitioners writing about histamine take a more conservative approach to their food recommendations so that those truly suffering can get some answers.
We practice individualized medicine in the clinic so there is no one size fits all as you well know Heather! Best to avoid foods that you know to be triggers.
Thanks for this article. I have been struggling with what I think is a histamine response and DAO insufficiency. After I eat, about 1-2 hours later, my nose runs and eyes water. The worst part though is the severe acid reflux in my throat. Recently I was feeling well and had some tea and this triggered me big time. The acid was horrible and my throat started to itch and I developed bumps on the back of my tongue. Then the diarrhea. This was days and nothing helped until I went on a liquid fast. 🙄 Prior to this I had been taking bovine kidney supplement as a source of DAO and had run out and forgot I ran out. Well, since starting to take it again, I am so much better. The acid in my throat is mostly gone and the diarrhea, watery eyes, etc. My goal is to heal my gut and fix the root cause. I’m glad doctors like you are writing about it. Between the bovine kidney supplement and quercetin with vitamin C I’m pretty stable. Have to avoid tea, bacon, lunch meat, canned tuna, and other things for sure though.
As a side note, I read about a study that Low FODMAP diet reduces histamine as well. Maybe getting rid of the excess bacteria? Not sure the mechanism but I’m trying to follow it.
yes, the low FODMAP diet treats SIBO and some of the SIBO organisms produce more histamine
would you care to share what bovine kidney supplement you are taking ? interested as I just found out about this thingy. I’ve eliminated all trigger-foods and drinks with leaky gut, fodmap and low-carb knowledge. but tanings have been plagueing me forever, until yesterday I had an eureka-moment. need to get my DAO-levels up until my gut is healed.
I was told that high doses of vitamin C is really good in boosting doa. Is this true?
Hi, I like your list of scientifically proven DAO boosters although I knew most of them already. However, I think you simplify lots of things too much. You are listing lots of foods which would have high levels of oxalates which bring up the histamines: nuts, seeds, many root veggies, greens, grains, potatoes, sweet potatoes etc. Olive oil, mackerel, avocados and more are full of histamines.
I started with co q10 last year and have found it extremely helpful. I stopped taking anti-histamines. Vitamin B6 foods help a lot with DAO formation.
I still have a problem with hydration and haven’t found a solution yet.
yes, of course Bridget! Diet must be personalized and in conjunction with your own needs… there is no one size fits all! 😊
Is there a DAO supplement brand you recommend?
I really like the Histamine Blocker here
Thank you for this article, which clears up a lot of confusion.
The things I love: tea, dark chocolate, vinegar, etc, are causing me problems. I have much to think about.
I have MCAS and histamine intolerance – struggling in fact even on meds. and having read all the above, am quite keen to consult with you when back in UK (away with work right now). However, immediate query is Im taking Wiley’s Alaskan Fish oil – do you think this is risky? It’s meant to be very pure and freshly caught with no nasties in it. Look forward to your thoughts. Many thanks Mark
No, I think that is fine
I mean to say the fish is Pollack that they make it from
Is there a brand of omega 3 that you know is pure? I use Nordic naturals because of their purity.
It would be great if you can clarify the following, I have terrible reactions to histamine and they are quite extreme, I was trying to determine if histamine is the cause or a symptom of a blocked lymphatic system because of like of bile to break down fats etc.. so I had a DAO test and it came back as 50U/ml concentration levels in the serum which is classed as good levels according to the test. But natural DAO takes away symptoms and Quercetin is really helpful to me.
How does DAO relate to mass cell activation syndrome? Could i still have histamine issues even though the DAO levels are ok?
And do you know a clear plan that we could take to resolve?
Yes, there are many pathways to histamine issues and MCAS and a normal DAO does not rule out other issues with histamine
Part of what you mention on this page is a real problem for me. For the past month or so I have suffered from severe skin itching involving virtually the whole body which I suspect could be histamine intolerance. Many of the foods that are listed as having high histamine levels are a regular part of my diet and I eat some of them in very large amounts. I also have problems with atherosclerosis and experience shows that eating saturated fats will increase arterial inflammation and deposits in the arteries. For this reason I am intentionally avoiding saturated fats. The results of past tests such as the blood test Lp-PLA2 and CT scans of the coronary arteries have convinced me that I need to avoid saturated fats.
I am intolerant of most vitamin supplements that would help to elevate DAO levels. I’m wondering if the Histamine Blocker can be taken before taking a vitamin supplement, to avoid a histamine reaction? Has anyone tried this? Any thoughts would be appreciated. Thank you
You might try it… But I suspect there may be an ingredient in the vitamins that you need to identify and avoid. Do you have trouble with all vitamins regardless of brand?
Thanks for responding. Yes, I have trouble with all oral supplements. Doesn’t matter the brand (vegan or not). I am very deficient in Vitamin D & B and have tried just about every supplement, without success. As a side note, I was given Vitamin B shots, prescribed by my PCP, that I tolerated very well, without reaction, but insurance won’t continue to cover.
I purchased your Histamine Blocker and waiting for it to arrive. Will report what I find.
Hi, I was diagnosed with SIBO and given Xifaxan and 1 month of probiotics. But the probiotics are not low in histamine. So I felt worse. Now I stopped the probiotics for 7 days and I am still experiencing excess acid in stomach (leading to abdominal cramps) at night and it affects sleep. I am still waiting for the probiotics to be flushed out of my system.
Hi Meng Lee,
Megaspore tends to work very well with SIBO. You can try that for now. I would avoid probiotics with lactobacillus.
I was recently pregnant. In my second and third trimester my migraines completely went away and through some research I discovered that this was due to my DAO levels being 500x greater during that time. Now my migraines are back and worse that before. I am trying to decide between the supplements d-hist and Umbrellux DAO. Is there a difference between these two? Should they be taken together? If not which one is better? My head is spinning! Thanks so much!
Histamine Blocker can be taken prior to meals to assist histamine breakdown and acts quickly. Hist Assist uses natural mast cell stabilizers and better taken daily for long term control. They can be taken together.
Question, is apple cider vinegar considered a trigger for someone with histamine intolerance or issues? When I drink wine, I either have severe acid reflux the next day or an allergic reaction of some sort including hives that last several days.
yes, fermented foods may be triggers for those with histamine issues.
I have finally figured out that I have MCAS and intolerance of histamine. It’s been about a year and I am now figuring out my triggers. I mostly stick with fresh foods and supplements. I am able to manage it now, but I did end up in an ER with massive uticaria all over and was suggested to travel with EPIPENS, which I do have now with me. I am learning my triggers and no longer drink any alcohol, stay away from fermented foods, and aged cheeses. etc. I have had to rework my diet, mostly just give up the bad foods and eat more clean, so I don’t feel I am missing out just adjusting to my body’s internal changes. I sometimes miss my glass of wine or a margarita once in a while, but the reaction I get from ingesting those keeps me away from them. It’s a learning curve. The body is not a stagnant organism and is constantly changing its inner environment and shows up on our external body signs and cues of the imbalance. The trick is to learn that trigger. I am finding that most of the medical pros I have seen on this matter are good at reading the symptoms, but have zero clue about MCAS. I have self diagnosed as I understand what my body is doing so, mostly I see a medical pro if I need an RX.
DAO is distributed beyond the gut.
“Lipids stimulate the release of diamine oxidase
into lamina propria for transport by the lymphatic to
the blood. Some diamine oxidase may be directed to the
intestinal lumen, particularly into the distal ileum.
Proteins stimulate the release of diamine oxidase into
the lumen only, and carbohydrates do not appear to
have a significant effect on the enzyme release. The
functional significance of the two secretory paths for
intestinal diamine oxidase is open for speculation. One
could argue that the increase in enzyme transport to
the extracellular location increases the degradative
capacity in the lamina propria and reduces circulating
polyamines and histamine, whereas the release of the
enzyme into the intestinal lumen, which is more pronounced in the distal small gut, may deal with the
bacterial polyamines and histamine (19). Therefore,
diamine oxidase appears to prevent the buildup of free
polyamines, histamine, and possibly other biologically
active substrates (10), creating a barrier between the
lumen and tissue interface in the mucosal and vascular
regions. The intensity of the protective actions of
diamine oxidase appears to be regulated by dietary
Wollin, A, wang, X, Tso, P. (2017) Nutrients regulate diamne oxidase release from intestinal mucosa). The American Physiological Society, 20, 220
A magnificent article. Thank you.
I agree Ella and love those things, too. I have not, however, been able to give up tea or dark chocolate. They say those of us that cannot tolerate vinegar, can tolerate apple cider vinegar. I tried adding some to dark leafy greens, but I took a Histamine Blocker tablet first. My reaction was lessened but may have also been due to something else. The jury is still out. Good luck!
oliveoilsource.com has it that olive oil is 10:1 Omega6-to-Omega3 ratios, so why are you advocating o. oil as some kind of O3 bonanza? I mean, THEY’RE olive oil ADVOCATES, so I doubt they’re selling themselves short.
I’m sorry to have to disagree with you, since I’m not a doctor (though I am currently a student of molecular and cellular biology) but you’re encouraging people to eat foods that are high in histamine or act as histamine liberators. Cashews are histamine liberators. Most fish that isn’t fresh or immediately frozen is extremely high in histamine, as is spinach and avocados. These foods are VERY dangerous for those with histamine intolerance from DAO deficiency and for those with any kind of mast cell disease or disorder.
I know a little something about this because I suffer from MCAS, diagnosed a few months ago by a dysautonomia doctor and confirmed by an immunologist. Several of the foods you mentioned in this article can trigger symptoms, including a life threatening anaphylactic attack.
Hi Katrina – I have updated the article to correctly read “Foods that increase nutrients listed above” These foods are rich in the nutrients needed to make DAO and this information is factual. I am not claiming these foods are low in histamine as that is topic you can read about in my article on MCAS HERE or my interview with Bob Miller HERE