So you’re probably wondering what histamines are, and what they have to do with your period right? We’re all familiar with antihistamines – those medications that stop the “itchy, sneezy, watery eyes” situations that come up mostly during allergy season or when we are allergic to another substance (other than pollen).

Well, histamines are what antihistamines work against!

What are histamines?

Histamines are chemicals that are stored in immune cells known as Mast Cells, and are involved in nerve transmission and immune response regulation. When Mast Cells are triggered, they release histamines, which then trigger those responses we all know so well – itchiness, puffiness, swelling or hives – which are all caused by your immune system.

Mast cells are not the only source of histamine in the body. Histamine can also be produced by bacteria living in the gut. In fact, certain gut bacteria not only produces histamine, but they can also help regulate it and even break it down. This is important so keep reading.

Important to note: Bacteria found in fermented foods like sauerkraut, kimchi, kombucha, and kefir also produce histamine.

Where do you find histamines?

Basically in all the good stuff! 🙂 I’ve noticed most people tend to react most strongly to the fermented foods on this list, but it’s important to know the other food triggers too.  

  • Fermented, cured, or soured foods, such as yogurt, luncheon meat, pickles, and sour cream
  • Aged cheeses, such as cheddar and goat cheese, and smoked fish
  • Citrus fruit and dried fruits such as apricots and raisins
  • Alcoholic beverages, especially wine and beer
  • Certain nuts, including walnuts, peanuts, and cashews
  • Avocados, eggplant, spinach, tomatoes, chocolate, and dairy

What is Histamine Intolerance?

When a person has a histamine sensitivity, certain foods or environmental stimulants can cause a host of symptoms.

Symptoms of Histamine Intolerance:

  • flushing
  • sneezing
  • itching and hives
  • headaches and migraines
  • wheezing
  • swelling
  • anxiety
  • runny nose or bloody nose
  • skin issues like acne and eczema
  • menstrual cramps, and
  • difficulty sleeping (hint: this is why antihistamines make you sleepy).

While genetics and food allergies certainly play a role in histamine sensitivity, gut dysbiosis makes things much worse. People with leaky gut or small intestine bacterial overgrowth (SIBO), or some other type of gut bacterial imbalance are much more prone to histamine sensitivity.

Histamines And PCOS

Women with PCOS tend to have lower progesterone levels because they don’t ovulate consistently. This is because the act of ovulation triggers progesterone production from the little follicle the egg was released from. 

Keep this in mind as you read the next two paragraphs…

We have a gene called the DAO gene that creates the DAO enzyme. If there are genetic mutations on this gene, you may not make the DAO enzyme sufficiently. This is important because the DAO enzyme is located in your gut, and it is responsible for breaking down histamine contained in the food you eat.

So here’s the connection to progesterone – the DAO enzyme function is naturally supported by progesterone. This is why women with PCOS may have more histamine issues than women who are regularly ovulating and producing sufficient progesterone.

Histamine and Estrogen

Estrogen actually triggers the release of histamine from the mast cells in the ovaries and uterus. The more unopposed estrogen we have roaming around our body, the more histamines are produced. And unfortunately, the more histamines we have, the more estrogen is produced. Ugh, and around and around we go in this cycle.

This is why it’s so important for women with PCOS or women who tend to be estrogen dominant to get in the know about histamine intolerance.

The estrogen connection is why women may feel really terrible at ovulation and notice an improvement in their histamine-related problems during the second half of their cycle when estrogen drops and progesterone rises. It’s frustrating for many women because they think they’re supposed to feel amazing at this time of the month, and instead they are plagued by headaches, fatigue, bloating, itching, insomnia, irritability and gut issues.

Is this you? Please share in the comments below!

It’s almost like PMS during ovulation. And while the symptoms improve for many women in the second half of their cycle (when progesterone is high), they come back as progesterone drops towards the end of the cycle. And hello PMS symptoms all over again!

And, keep in mind that during periods of extreme stress when we are diverting progesterone production to cortisol, you may also notice worsening symptoms.

Histamines and Menstrual Cramps & Abnormal Uterine Bleeding

You know how I just mentioned that histamines are released in the uterus? Well, they’re released so that the uterine muscles can contract during menstruation and also during birth. (1) 

This is another reason to consider histamine intolerance if you’re experiencing cramps and have tried implementing other measures to address them – change in diet, supplements, exercise and physical work (pelvic physical therapy, maya abdominal massage therapy or vaginal steaming).

In addition, there is some evidence that excessive uterine bleeding is associated with histamine release. (2)

What to do if you have a histamine intolerance

Ultimately, I think that women with PCOS or an imbalance in their sex hormones (namely estrogen dominance and low progesterone) definitely need to experiment with avoiding histamine triggers. Other symptoms of this imbalance include heavy or abnormal uterine bleeding, longer periods and conditions like endometriosis (I discuss the link between endometriosis and mast cell/histamine problems in this post). 

If you’re unsure about whether or not you have a hormonal imbalance I recommend getting tested.  You can now do this from home with Lets Get Checked, my go-to provider for at-home hormone testing kits for myself and clients. You just order them online, have the kit shipped to you, then do the tests at home and send the kit back in the mail. One and done.

And after processing, their team of physicians will review your results and a member of the nursing team will call you to deliver the results and discuss treatment options.

Be sure to use discount code Hormones20 to get 20% off all their tests!

Solutions for Histamine Intolerance:

#1. Avoid foods high in histamines

First, I suggest avoiding the foods below for just 2 weeks to see if there is improvement in symptoms. This is restrictive but I promise you’ll see results pretty quickly:

  • Fermented, cured, or soured foods, such as yogurt, luncheon meat, pickles, and sour cream
  • Aged cheeses, such as cheddar and goat cheese, and smoked fish
  • Citrus fruit and dried fruits such as apricots and raisins
  • Alcoholic beverages, especially wine and beer
  • Certain nuts, including walnuts, peanuts, and cashews
  • Avocados, eggplant, spinach, tomatoes, chocolate, and dairy

#2. Supplement with Quercetin

I am also a big fan of Quercetin, a flavonoid which works like an all natural anti-histamine – stabilizing the effects of histamines released from mast cells. It also doubles as a leaky gut and pain reliever. I suggest using it when you have a histamine reaction, and not daily or in the long term. I like Cardiovascular Research Quercetin-C which works amazingly fast thanks to its liposome enhanced delivery system. Follow the directions on the label. 

Remember, if you’re using anti-histamines for any length of time, they can disrupt your cervical fluid production, causing less fertile quality cervical fluid. This is because anti-histamines are mean’t to “dry out” your bodily fluids (like phlegm!). This is why Quercetin is a better bet.

#3. Avoid soil-based probiotics

Stay away from probiotics that are soil-based, which appear to trigger histamine issues. Instead take a look at Seeking Health Probiota HistaminX which contains Bifido strains that don’t trigger histamine problems.

#4. See your doctor

Finally, histamine intolerance is not usually an isolated incident in your body. When is anything ever isolated? LOL So I recommend seeing a functional doctor or naturopath to address any underlying gut issues and infections, and other contributing factors to your symptoms.

Hopefully implementing these solutions helps improve your histamine issues, which will go far to help your PCOS and PMS symptoms, and your abnormal bleeding.