Another way your gut affects food sensitivities…

There is a ton of information out there about how important gut health is to your overall health.  Seems like "heal your gut" is the answer to everything!  If only it were that simple.  

When we talk about food sensitivities and allergies, though, we can leverage your gut in a pretty straightforward way!  We've been talking a lot about different genes and enzymes in your body which help clear histamine.  

This week, I would like to introduce you to DAO.  

DAO, or diamine oxidase, is like the others - a gene (with the name AOC1) which codes for an enzyme.  And an enzyme is a protein with a job.  It really can be as simple as that.  DAO is an enzyme which works a lot in your gut where it helps break down the histamine in the foods you eat and the histamine made by an unbalanced microbiome.  It helps minimize symptoms like diarrhea, cramping, flushing and hives.  We're going to focus on the food side of this one.  

Your genetics can be coded for this enzyme to be plentiful or lacking…or just right.  But genetics don't have the final say!  The decisions you make about what you eat and the medications you take impact how much DAO you have available in your gut.  

How to support DAO

A low histamine diet is frequently one of the recommendations for someone dealing with histamine intolerance or food sensitivities.  The foods you eat have differing amounts of histamine or a compound called tyramine, which cross-reacts with histamine.  A true low histamine diet can be a real challenge.  My suggestion is always to decrease how much histamine you are currently getting in your diet or embrace a "low(er) histamine diet".  Need some help figuring out what to eat and what to avoid?  Here is some info on an app that can be really helpful!

This kind of diet makes sense for any of us struggling with histamine intolerance because you actually decrease the amount of work this enzyme has to do if you avoid high histamine foods like tomatoes and spinach and alcohol.  And if you keep the whole genetic community concept in mind - because DAO is not working in a vacuum - you're also taking the pressure off HNMT and MTHFR and MAOA and others we'll soon talk about!  

Antihistamines and DAO

If you get nothing else out of this post, READ THIS!  The medications you take can decrease the amount of DAO available in your gut to help with histamine.  The crazy thing is the antihistamines you take to help with allergies and food sensitivities decrease DAO in your gut.  Talk about irony.  Even Metformin, a common diabetes medication, cuts down on your DAO.  That doesn't mean you need to immediately stop medications (and I would recommend you discuss with your doctor first) but it means you need to learn how to support DAO in other ways, like choosing lower histamine foods. 

Replacing DAO

Of all the genes we'll talk about, this one is especially unique because you can actually take a supplement with your meals that simply replaces DAO in your gut.  And I can tell you from personal experience, it makes a huge difference in food reactivity!

Special DAO for baby!

One additional little nugget about DAO.  While this enzyme is primarily located in the gut, for pregnant women the placenta makes a crazy amount of DAO to help protect the baby from the mother's immune system.  That's one reason why a lot of women feel FANTASTIC while they're pregnant and then allergies and gut issues rage again after delivery.  

Sixty-second Self-care Tip…

One of the most eye-opening steps in the food sensitivity and histamine intolerance journey is starting to learn which foods are high histamine - because even some really healthy stuff can be really high in histamine!

Here is a short list of foods known to be high histamine.  Are any of these among your daily food choices?  How can you replace them with lower histamine foods and what changes would that cause in your symptoms?!

High Histamine







Almond Milk

Rice Milk

Cheddar cheese


Hard cider

Each week I'm introducing a new gene/enzyme which impacts histamine in your body.  In a few weeks, we'll put it all together!  And if you want to dive even deeper, join the waitlist for Food Sensitivity Code!


60-second self-care, antihistamines, DAO, histamine, low-histamine woe

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