Ep.7 Hormones and IBS – How your period makes your digestion worse
4 Jul, 2023

Episode Intro

Do you find your IBS gets worse around your period? It can be extra challenging at certain times of the month to keep digestive issues under control and in this episode of the Inside Knowledge, I'll share with you how your hormones affect your digestion and how your digestion affects your hormones. I'll be explaining why you might get period poos, and yes that is a real thing, as well as explaining why you might get constipated in the run up towards your period and what you can do about it. Even if your perimenopausal and your hormones are all over the place. There are things you can change through diet and lifestyle that will help your hormones and your IBS.

Podcast transcript

I’ve been meaning to do this episode for quite a while. I’ve had loads of requests to talk about hormones and IBS and periods and how it can affect your digestion.

I’m Anna Mapson. Welcome to episode seven of the Inside Knowledge where we’re going to dive into hormones and IBS.

Get your questions answered each week on Instagram

Before we get started, I just wanted to mention that on Instagram every week  on a Thursday after the episode is released as a podcast on a Tuesday, I do a Q&A.

If you listen to this in the week in real time before Thursday, you can pop over to my Instagram and put some questions into my DM inbox. Or into the question box on stories. Have a look at the questions that I’ve answered after the podcast episode has aired because I dive into sometimes like deeper dives. Or people have asked additional questions. Sometimes it’s things that I wish I’d included in the podcast but I didn’t include in the content.

Not enough research on women, hormones and IBS

So, unfortunately, a lot of women get excluded from scientific research projects. Because of, well, hormones! Often researchers exclude females on the basis that hormones make things more complicated. It’s like, yeah, we know that. But we do often get excluded from drug trials and things are tested on an average size man.

Female sex hormone changes throughout the month are often ignored. But they can have a huge consequence on how you feel and how your body works.

And if you have periods you will know this very well! Throughout the month we do get these massive changes. Female sex hormones do not just prepare the body for pregnancy.

They change our mood, our skin, energy, so many things. It’s not just about, reproduction. There are cell receptors for oestrogen and progesterone in the gut. So it makes sense that you could potentially get changes to your digestion throughout the month.

Women are more likely to get IBS

We also know that almost twice as many women get IBS as men, and this could be down to the effect of the sex hormones. Women with IBS are much more likely to experience premenstrual anxiety. Much more likely to get painful periods. And if you have IBS, it’s going to be worse during your period.

The other thing is during perimenopause, symptoms can really worsen. And at the end, I’m going to speak a little bit about the effect of HRT. And also perimenopausal symptoms because that’s a whole other ballgame.

Your menstrual cycle recap

A little quick recap of the menstrual cycle. I’m sure you probably know this, but just as a quick reminder of what I’m going to be talking about in this episode.

Normally we say the menstrual cycle starts on day one of your period. That’s the beginning your cycle. The cycle runs until the next period so it’s often around 28 days. That’s the average, but it can be anywhere from 24 to 35 and is considered normal. What we’re getting is a period of, somewhere between three to seven days of actual bleeding.

Then you’re getting a follicular phase where your body is preparing to release another egg.

Then you have ovulation. That’s when the egg is released and then a luteal phase. Which is where your body is kind of laying down the womb lining, thickening it in preparation for a potential pregnancy. And if that doesn’t happen, then you’ll have another period and another cycle will start.

So roughly that is what you’re getting each month.

Tracking your hormones and IBS

There are massive variations and I ask all my clients about this, like how long is your period cycle? How long is your actual bleed? And there’s huge variation and a lot of it is considered normal.

It is really good to start tracking it, and if you haven’t listened to episode 5, go back and listen to that, and I specifically talk about tracking your menstrual cycle alongside your digestive symptoms.

And whilst you can track in the short term to look for things like food intolerance, it’s also really good to track long term throughout the month to notice changes that are more steady and that might be, only appearing as you’re looking at patterns… throughout the month.

So, in the background, that’s happening with your sex hormones, but what is happening, and how does that affect your digestion?

Increased digestive symptoms throughout the month

Well… you can get… Increased sensitivity of your large intestine and particularly rectal sensitivity for women who’ve got IBS around the actual period. So at the start of your period, you get increased hypersensitivity.

That can increase that feeling of incomplete evacuation that is really common in IBS.

And this has been shown in studies when compared to women who don’t have IBS. People who do have IBS generally get a lot more sensitivity around that time of the month.

Slowing down of digestion before your period

Before your period you may experience a slowing down of digestion. And constipation can be more predominant. Then often you get might get loose stools where you get a couple of days of diarrhea alongside the bleeding. That can be very common as well.

Even your hormones can affect how full you feel. So we’ve also noticed in studies is that the rate of your stomach emptying is likely to change. During your luteal phase, that’s the second half of your cycle, you might get quicker gastric emptying. So your stomach is emptying into your small intestine up to 28 minutes faster than during the first half of your period.

Now that could lead to you feeling like you want to eat more. Being more hungry in the run up to your period is also a common symptom.

It also could affect how well broken down your food is, so it could lead to additional bloating. So you can see how it can really… Effect the speed of transit time, the ability of your body to break the food down.

Um, we also know that hunger hormones change throughout your cycle. Through the rise in progesterone as your body is preparing for the period or like thickening, the womb, you can get a rise in progesterone.

That can also increase hunger. So let’s talk a little bit about some of those and break them down a bit.

Worsening of constipation around your period

IBS constipation around your period is very common. This is because your body is starting to slow down gut transit time. In order to allow for proper nutrient absorption. It’s also been shown in studies that stool consistency is firmer.

So basically your poo is harder to pass. And you might have a longer transit time. This is because your body’s trying to extract as much goodness from your food as possible.

The dreaded period poos

And then what happens is you get a release of this as your period starts. Around day one or day two and you can get diarrhoea. That sort of increased urgency, looser, maybe more foul smelling bowel movements that coincide with getting your bleed. Now this is down to, again, the hormones that are called prostaglandins.

These are like little local hormones which help the womb contract to release the blood. That has built up inside. But they can increase the contractions of your gut so they can basically give you more digestive cramps, increase your pain sensitivity and just cause your bowel transit time to speed up. Which can result in diarrhoea because the food is passing through you quicker.

It might be less broken down and can cause more fermentation, which can add to the gas and the odour.

How to help digestion and hormones

If all this has left you feeling, “yeah, I know, I get all of that, what can I actually do about it?” I’m gonna just go through a few things now which may help.

How to eat in order to try and minimize those symptoms alongside your hormones.

1. Start tracking

Firstly, tracking. If you’re not already doing this, you need to start tracking your digestive symptoms against your menstrual cycle. This is particularly helpful if you do not have a regular cycle.

If your hormone cycle is all over the place, the point of ovulation could be really quite different each month. It’s important to know, because I found, using this tracker, that a lot of people get more symptoms around ovulation as well as at their period. It can be a real point where people are getting more bloating. Maybe more pain or gas and this is down to a big increase in the hormones.

Oestrogen and progesterone are known to affect your smooth muscles. So, these are the muscles which are not under the body’s conscious control. Things like, our gut transit time. Like, we can’t control with our brain how that is moving. Same as, like, shivering, you know, we can’t really control that.

So these smooth muscles are affected by oestrogen and progesterone, which is, you know, why it’s affecting your gut transit time. So definitely start tracking. If you’re not already doing it, just start today.

2. Increase hydration

In your premenstrual phase, so this is in the run up to your period. I would say increase hydration.

Often you can get a bit of water retention around your period. That’s nothing to do with gut bloating, it’s just like a hormonal bloating. And increasing your fluids can actually help to kind of… help your body to wash all that away, so you get less bloating.

3. Eat a high fibre diet

Also, focusing on fibre, because you want to try and minimise the amount of constipation.

You want to try and keep your bowels as regular as possible, keep them moving. And the best way to do that is to eat more fibre containing food, particularly fruits.

So I’d say, if you find a real problem with bloating, try to go to those low FODMAP type fruits.  Like oranges, berries, kiwi. . Really eat two to three to four portions of fruit a day in order to try and keep your bowels more regular if you are prone to constipation.

So if that’s a problem for you, then you need to try and keep things moving particularly extra during that week.

4. Avoid gut stimulants

It’s also really common in the week before your period to feel a little bit tired, maybe a bit more irritable, maybe a bit more stressed and anxious.

Often, in those situations, people might turn to an extra glass of wine to help you relax. A little bit extra caffeine to help get you up in the morning. But actually, these things can also contribute to your gut symptoms.

So, trying to manage your tiredness, your anxiety, your stress, whatever, with, non gut stimulants like alcohol and caffeine.

5. Gentle movement

So ways you can do that would be like gentle sort of exercise. That really helps, going for a walk. Really trying to find things that you enjoy that are calming trying to balance out your life.

Without relying on those stimulants that pull us through when we’re feeling really tired. And I know you might feel like, “Doing some yoga is not the same as having a glass of wine or having an extra coffee mid morning!”

But actually longer term, it might be worth it. Just to give those things a little rest for a month or two in that a few days around your period.

Gut bacteria can affect your menstrual cycle

Now, I also want to talk about how your gut bacteria can affect your hormones. How your digestion can interact with your sex hormones, and how that could maybe, influence your premenstrual symptoms.

So, in our digestive tract, you’ll have heard me talk a lot about the gut microbiome. That’s just a collection of microbes, bacteria, viruses, fungi living in your digestive tract. And these can interact with hormones.

There are certain types of bacteria which produce an enzyme called beta-glucuronidase. Which can reduce the detoxification of oestrogen from your gut.

Normally to get rid of oestrogen that we don’t need anymore, our liver will cut it up and make it water soluble, so it can be excreted in urine or in your poo.

But beta-glucuronidase is an enzyme that unhooks the oestrogen from its water soluble transporter.

Oestrogen reabsorption

So, it can then potentially be reabsorbed into the body. Where you’ve got a lot of this beta-glucuronidase producing bacteria, it may lead to you having higher levels of circulating oestrogen.

What you’ll also find is this oestrogen that could be reabsorbed from the gut back into the body is a different form of oestrogen that can be more potent. So it could potentially be leading you to get more of those PMS symptoms such as sore breasts, premenstrual acne, mood changes and insomnia.

And this is another reason to try to focus on regular bowel movements. If you’ve got constipation at a really slow transit time, food waste is sitting in your large intestine for a long time. There’s more time for this beta-glucuronidase to get to work and to unhook oestrogen. And for it to be reabsorbed.

So you see, there is a way that your gut bacteria and your digestive speed can affect your hormones as well as your hormones affecting your digestion.

Stool testing

If you’re wondering what you can do about it. If you’ve got some microbes that could potentially be doing this, you can check by getting a private stool test.

They are around £370, so quite expensive. They will look at specific types of bacteria that produce beta-glucuronidase. Some stool tests will actually test specifically for that enzyme in itself.

But even if you don’t know how many of these bacteria you’ve got. The one thing you can do is to eat a more diverse diet with lots of different types of plant fibres. Because this is one of the key ways to increase your diet diversity and your gut diveristy.

So, wherever you are with your diet, adding more variety, adding more fibre is generally a good way to try and build up gut bacteria.

Perimenopause and IBS

It’s really hard during the perimenopausal phase, when your hormones are changing.

To the extent that you don’t know where your cycle is.

You may be skipping a cycle, you might have gone down to really short cycles, like 21 days or shorter, even 17 days or something between periods.

So you never know what’s happening. You never know when you’re ovulating, or when you’re premenstrual. Or when your period’s about to start, because things are happening all the time, and it can feel very out of control.

It can affect your digestion in the same ways that I’ve been talking about it’s just that you won’t see the regular pattern, and that is why it is so challenging.

Inceased anxiety around perimenopause

I also want to really recognize that alongside a lot of the perimenopausal changes, that you can often get increased anxiety.

That is partly down to the change in hormones, but also it’s a really massive change in our lives. And when everything seems to be falling apart in your body and changing outside of your control, it can be very difficult.

To ease the symptoms of the perimenopausal period, many women turn to HRT. And that’s a replacement hormone that’s going take the place of these hormones that are cycling out of control.


There’s lots of different types, there’s lots of different ways of taking HRT. The main thing is that you’re putting a hormone into your body and for some people, it can make their IBS worse.  But I also want to say some people it makes their IBS a lot better. Because it will regulate your cycle and allow you to see where you are.

I think we’re getting a much better sense of menopause now. People seem to be talking about it a lot more freely than they were years ago.

We’re also really understanding that if you go through menopausal symptoms in your 40s you could have half of your life left. So without oestrogen you are potentially at greater risk for things like osteoporosis, for, Alzheimer’s, and these things are seen in higher levels in postmenopausal women.

So there’s lots of plus points for taking HRT, although I know it’s not suitable for everyone, and not everyone will be able to access it, and not everyone gets on well with it when they take it.

But… There are lots of benefits to being able to regulate your cycle again and regulate your hormones again.

Does HRT make IBS better or worse?

So, just to bring it back to IBS, because that’s what this podcast is about, I did some research trying to look at HRT and the risk factors for IBS.

It’s mixed, I would say. Sometimes there’s no effect found, although the research is limited, but what I would say is… Try different types of HRT.

Try to find something that works for you because there are lots of different ways of having it. Different doses and different forms of oestrogen. Different forms of progesterone that can help.

And it might help to get your hormones under control, may help your digestive function.

And if you find it’s making it worse, go back to the doctor. Tell them it’s not working for you and you need a different form of help with your hormones.

To summarise this episode

Let’s just summarize a little bit this episode.

  • What I talked about is tracking, track your digestive symptoms against your cycle. Start today if you’re not already doing it.
  • In your premenstrual phase, make sure you’re focusing on hydration, movement, and fiber. And if it needs to be low FODMAP fiber, do that. But make sure you are getting things in that are going to help you move your bowels and try to minimize constipation.
  • Generally, if constipation is a problem for you, we can see a correlation between constipation, slow transit time, and those beta glucuronidase producing bacteria. So again, just focusing on trying to get your gut moving. Generally, getting as much diversity into your diet as possible, aiming for 30 grams of fiber a day with maybe 30 different plants a week. That’s a good target, but see where you are from now and increase it gently.
  • And then during your period, try to avoid any gut stimulants because these can increase loose stools. Things like alcohol, caffeine.
  • And you might find it helpful to go low FODMAP just for a few days around your period, which may help you reduce some of the fermentation that can come with the loose stools, particularly if your diarrhea is kind of frothy, smelly, and painful.
  • And then, apart from that, just throughout the month, really thinking about prioritizing sleep, rest, things that bring you joy, you know, just all the basics, all the good things that are going to help for normal IBS management are also helpful for, hormone management too.

Right, I better leave it there I will see you next week. Thanks for listening.

Ep.59 – How to get better sleep when you have IBS

Sleep and IBSHello, welcome to episode 59 of the Inside Knowledge. I'm Anna Mapson. The reason for picking sleep as a topic for a podcast is that a lot of my clients really struggle with sleep. It can be down to things like waking up because your symptoms are waking...

Ep.58 – Case study – Vegan slow transit constipation to normal

Sian's IBS story - vegan diet with constipationWelcome to episode 58 of the Inside Knowledge. I'm Anna Mappson. Choosing case studies to share with you is always really good. It gives me a chance to reflect a little bit on What's gone well and actually how my practice...

Ep.57 – Should we be eating 30 plants a week

Should we eat 30 plants a weekWelcome to episode 57 of the Inside Knowledge podcast for people with IBS. I'm Anna Mapson. You've probably heard me talk a lot on this podcast already about the importance of diet variety to help feed our gut bacteria and cover essential...

Ep.56 – IBS advice to ignore by an IBS nutritionist

Breathing techniques for IBSWelcome to episode 56 of the Inside Knowledge podcast. I'm Anna Mapson. My podcast has turned one this week. I've been running weekly episodes for a year now, and I wanted to take this time just to reflect a little bit on things that I have...

Ep.55 – The truth about stomach acid

The truth about stomach acidWelcome to episode 55 of the Inside Knowledge podcast. I'm Anna Mapson. Today I want to talk about stomach acid and particularly about low stomach acid and not having enough. I think I will do a separate episode on high stomach acid or...

Ep.54 – Hidden IBS trigger ingredients

Breathing techniques for IBSWelcome to episode 54 of the Inside Knowledge podcast for people with IBS. I'm Anna Mapson. This episode is going to highlight a couple of things that you might be seeing in your food ingredient listings that could be contributing to your...

Ep.53 – How your childhood eating could be affecting your IBS

Breathing techniques for IBSwelcome to episode 53 of the Inside Knowledge podcast for people with IBS, I'm Anna Mapson. In my work as an IBS nutritionist, I work with people all over the world who have all different kinds of relationships to food I find it so...

Ep.52 – The possible cause of your IBS-Diarrhoea

Breathing techniques for IBSWelcome to episode 52 of the Inside Knowledge podcast. I'm Anna Mappson. The reason I selected bile acid diarrhoea as a topic for this week's podcast is that I see it quite often linked with SIBO, that is small intestine bacteria...

Ep.51 – How to increase your appetite with IBS

How to increase your appetite with IBSWelcome to episode 51 of the Inside Knowledge podcast. I'm Anna Mapson. This episode is to follow on from the previous one, which was about how to gain weight. I realized when I got near the end of this episode, I had loads to say...

Ep.50 – How to gain weight with IBS

How to gain weight with IBSWelcome to episode 50 of the Inside Knowledge podcast. I'm Anna Mapson. This episode I've been meaning to record for a little while. I did two episodes a few weeks ago about how to lose weight. And that was also a popular request. But how to...