Is Your “Safe” Food List Getting Smaller? Histamine, DAO and the Perimenopause Connection

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First you thought it was dairy.

Then gluten 

Then alcohol.

Then perhaps tomatoes, avocado, smoked fish or leftovers.

Now you’re wondering: “What can I actually eat?”

You stop drinking wine because you think you've figured out the problem. Then you have shrimp with avocado at a restaurant and suddenly your face is bright red, your stomach is gurgling, your nose is running and you feel like your body has completely turned against you.

And this can be incredibly confusing and it seems to be happening a lot in perimenopause.

You have always eaten these foods without a problem. So why are you suddenly reacting to everything?

Sometimes the problem isn't simply the food. It is your body's changing capacity to deal with the total load.

And this becomes particularly interesting during perimenopause.

It may not simply be the food

One of the most frustrating things I hear from women in perimenopause is: “I used to be able to eat this. Why can't I tolerate it anymore?” or “I seem to react randomly to all kinds of foods now”...

And I understand this very well because I've had to investigate it in my own body, too.

I never used to think of myself as someone with a histamine problem.

But this past year, I began experiencing symptoms including skin inflammation (redness), watery and swollen eyes, congested sinuses or runny nose, migraines, digestive gurgling, bloating, constipation, nighttime palpitations and difficulty falling asleep.

In my case, there was also a very specific factor that seemed to add to that load: my dental retainers (Invisalign).

They created a structural and nervous-system stressor for my body, and I noticed that my symptoms developed after I started wearing them.

That doesn't mean retainers cause histamine intolerance.

It is simply part of my total-load picture.

But I also started noticing a clear pattern around food and histamine.

And the more I looked into it, the more I realized that histamine tolerance is not just about histamine.

It is about your capacity to process it.

And that capacity can change.

Why can histamine suddenly become a problem in perimenopause?

We tend to think about perimenopause in terms of estrogen and progesterone. And those hormones absolutely matter:

• Estrogen interacts with histamine and mast-cell activity, and hormonal fluctuations may make histamine-related symptoms more noticeable in some women. Research into the relationship between menopause, hormones, histamine and allergic symptoms is still developing.

• And Progesterone helps your body to decompose histamine

So you see that perimenopause creates the perfect storm: increased histamine with fluctuating estrogen and lower clearance with low progesterone plus that extra cortisol that comes with low progesterone.

But there is another piece of the puzzle that I recently learned about - and it really made me stop and rethink my own experience: DAO.

DAO stands for diamine oxidase, an enzyme that plays an important role in breaking down histamine from food, particularly in the gastrointestinal tract.

And some clinicians working in women's hormone health are increasingly discussing the possibility that our ability to produce DAO may decline as we get older.

Dr. Carrie Jones has spoken about this specifically in relation to why women may tolerate foods in their 20s that suddenly become problematic in their 40s. Her recent Hello Hormones episode also explores DAO, histamine and the sudden increase in food and allergy-type reactions that some women experience during perimenopause.

Now, I want to be transparent here: this isn't yet a firmly established scientific fact.

So let’s not assume that every woman (or man) automatically produces less DAO after 40.

But I do think the idea is worth paying attention to - particularly when we look at the bigger picture of how digestion and food tolerance can change as we age.

And it made me wonder if: changing DAO capacity could be one reason why foods I tolerated for decades suddenly became harder for me to handle?

DAO is only one piece of the histamine puzzle

DAO is particularly important for histamine coming in through food.

But it isn't the only way your body handles histamine.

Another important enzyme is HNMT (histamine-N-methyltransferase), which breaks down histamine inside cells in your liver.

And then there is your gut.

Your intestinal lining.

Your microbiome.

Your immune system.

Your nutritional status.

Your hormones.

Your genetics.

And everything else contributing to your overall physiological load.

So taking DAO may help some people, but it isn't necessarily the whole answer.

The more important question is: Where is my histamine-processing capacity being challenged?

My own histamine detective work

This is where my own story became particularly interesting.

Genetic testing showed that I have several potential weak points in pathways involved in histamine clearance and methylation, including slower HNMT and COMT pathways, an MTRR variant and deletions affecting some GSTM genes involved in detoxification. In simple words this means that my body tends to accumulate things and my liver has a harder time or needs to work harder at clearing all these things.

I don't see these genetic variations as diagnoses. They are simply pieces of information.

And this is an important distinction: The genetic variation was there all along. It didn't suddenly appear when I entered perimenopause.

What can change is the environment in which that genetic tendency is operating.

If your total physiological load is low, you may never notice a particular weakness.

But add hormonal fluctuations, chronic stress, poor sleep, gut dysfunction, inflammation or environmental exposures - and a pathway that previously coped perfectly well may suddenly become more relevant.

Your genes can create potential weak points.

They don't have to determine your destiny.

Then my gut microbiome gave me another clue

My stool testing showed that I had virtually no detectable Bifidobacteria.

That caught my attention because gut bacteria can influence the metabolism of histamine and other biogenic amines. The relationship is complex - different bacterial strains can produce or degrade these compounds - but it made me wonder whether my gut microbiome was contributing to my own histamine burden.

So I slowly introduced Bifidobacteria. And I noticed something quite remarkable: I could eat more foods again.

My allergy-type symptoms improved.

My stomach was less gurgly.

And my safe-food list started getting bigger.

That doesn't mean Bifidobacteria “cured” histamine intolerance.

It simply gave me another piece of my own puzzle.

Vietnam helped me understand part of this picture

I noticed something else that I couldn't ignore.

When I was in Vietnam earlier this year, my skin cleared up immediately after months of battling with redness and inflammation. The climate may have had something to do with it, but one of the biggest differences was my food: I wasn't eating any leftovers.

At home, leftovers had been a normal part of my routine (and in case you are wondering: leftovers - especially animal protein = high histamine accumulation)

So I can't say that fresh food was the reason I felt better. But it was another clue.

My tolerance wasn't fixed.

It changed depending on the circumstances.

And that is exactly what you might expect when you're dealing with a combination of factors rather than one isolated food intolerance.

This is where the idea of “total load” becomes so important

Think of your body's capacity as a bucket.

Maybe ten years ago, your bucket had plenty of room.

You could have a stressful week.

Sleep badly for a few nights.

Drink some wine.

Eat leftovers.

Go out to dinner.

And your body could cope.

But then life happens.

Hormones fluctuate.

Sleep changes.

Stress accumulates.

Digestion becomes less efficient.

Your gut microbiome changes.

Environmental exposures add to the load.

And suddenly your bucket is already 80% full. That glass of wine isn't necessarily the whole problem. It may simply be the last drop.

This concept of total load is one of the central ideas I explore in my book, Stranger in Your Body. (Upcoming release on 18th November 2026)

It is also why I developed the SENSE framework: because I don't believe we can understand a symptom by looking at one gene, one food, one hormone or one enzyme in isolation.

We have to look at the whole system.

What is adding to the load?

What has reduced your capacity?

And which systems need support?

So should you just avoid all high-histamine foods?

Not necessarily.

A temporary reduction in histamine-rich foods can be useful for some people while they investigate their symptoms.

But I don't want you to end up with a list of five foods that you're terrified to move beyond. You know that I’m not a friend of diet restriction - not only does it restrict you, it also restricts your microbiome and digestive capacity. 

The goal should be: “How can I increase my capacity?”

That might mean supporting digestion.

It might mean looking at gut health and your microbiome.

It might mean addressing constipation or sluggish elimination.

It might mean reducing inflammatory triggers.

It might mean supporting nutritional deficiencies or specific metabolic pathways.

It might mean using hormone therapy. 

It might mean temporarily reducing histamine exposure.

And for some people, DAO may be one useful tool.

But it is a tool - not necessarily the answer.

Your safe-food list doesn't have to keep shrinking

If you're in your 40s and suddenly feel as though your body is reacting to everything, you're not imagining how confusing that can be.

But you also don't necessarily have ten new food intolerances. Your threshold may have changed.

• Histamine may be part of the picture.

• DAO may be part of the picture.

• Your gut microbiome may be part of the picture.

• Your genetics may add another layer.

• And perimenopause may be changing the background conditions in which all of these systems operate.

This is why I don't want you to simply chase the symptom and eliminate another food.

Instead, ask: “What has changed in my body that means I can no longer tolerate what I used to?”

That question opens up a very different path forward.

Because the goal isn't to spend the next ten years eating plain chicken and rice.

The goal is to understand why your capacity has changed - and gradually give your body back the ability to handle more.

Your body isn't betraying you.

It may simply be telling you that something has changed.

The question is whether you listen to the symptom… or investigate the system behind it.

Frequently Asked Questions

Why am I suddenly reacting to foods during perimenopause?

Perimenopause can bring major changes in estrogen and progesterone, alongside changes in sleep, stress resilience, digestion and immune regulation. These factors may influence your tolerance to histamine and other food-related triggers. Many women certainly see an increase in allergies in perimenopause, so there is definitely a relation. 

What is DAO?

DAO, or diamine oxidase, is an enzyme that plays an important role in breaking down dietary histamine, particularly in the gastrointestinal tract.

Should I take a DAO supplement?

DAO supplements may help some people, particularly around meals containing more histamine, but they aren't necessarily the solution to the underlying problem. Histamine tolerance is influenced by multiple pathways and factors.

As you’ve seen, your problem may be more linked to liver congestion (HNMT) or methylation or all of these. So it’s always wise to investigate them properly and support all the areas instead of creating a new bottleneck. 

Can genetics affect histamine clearance?

Potentially. Variations in genes such as AOC1/DAO and HNMT, as well as genes involved in methylation and detoxification, may create individual differences in how we handle certain biochemical pathways.

But a genetic variation is not a diagnosis.

Why does my food tolerance change from day to day?

Because your overall load changes too.

Stress, sleep, hormones, allergens, gut health, food freshness and other factors can all contribute to how much capacity you have on a particular day.

That is why the same food may be completely fine one day and problematic the next.

Can gut bacteria affect histamine?

Yes. Research shows that different gut bacteria can produce or degrade biogenic amines, including histamine. The relationship is complex and highly strain-specific, which is why the goal shouldn't simply be to “add probiotics,” but to understand the wider gut ecosystem.

Why does histamine intolerance seem to become more common during perimenopause?

Perimenopause changes the hormonal environment and can coincide with changes in sleep, stress resilience, immune regulation, digestion and gut health.

Research into the specific relationship between menopause, mast cells and histamine is still developing, so it is better to think of perimenopause as a potentially important change in the background conditions rather than a single cause.

If your safe-food list is getting smaller…

Before eliminating another food, pause and ask yourself: “Why has my tolerance changed?”

Because sometimes the answer isn't another food you need to remove.

Sometimes it's a system that needs support.

And that is ultimately what Stranger in Your Body is about: understanding the system behind the symptom - and learning how to work with your body again.