Why is PMS worse in the heat?

Discover why the heatwave might be exacerbating your premenstrual symptoms.

Naturopath, Herbalist and Yoga teacher (BA, Dip Nat, Dip Herb)
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20 July 2022

Hello, and welcome to "Siobhán Talks Periods." My name is Siobhán Carroll. I'm a naturopath and a herbalist, and I'm really passionate about periods.
And this week, I've got a lot of questions from people asking, "Why is my PMS worse in the heat wave?" So today, I'm going to be talking about why the heat, especially when we're not used to it, can make PMS feel worse.

Why is PMS worse in the heatwave?

Many women find their PMS symptoms are worse during a heatwave. Hot weather may contribute to worse PMS thanks to dehydration, difficulty sleeping, an inability to regulate our inner temperature in the sudden hot weather, and even due to the stress many of us experience in this heat!

1. Hot weather causes some of us to be hot headed!

So, for starters, the hot weather can definitely make us all, regardless of our periods, whether we get them or not, it can make us all more hotheaded, you know, especially when we're not used to the heat!

For me, as an Irish person, definitely, I think, probably, the majority of people who live in the UK and Ireland, we really crave this heat. And then when it comes, we kind of suffer a bit because our body's just starting to get used to it. So there is that. You know, if you're prone to the sort of irritability, anger, and frustration, and symptoms like emotional symptoms that arise in those premenstrual days, this hot weather can definitely exacerbate those PMS symptoms.

2. Temperature changes can affect hormone balance

The second thing that can occur, for some women, is a sudden, kind of, change in temperature where there's a heat wave or if you're going on holiday somewhere hot any time of the year. We've got that quick change in heat. That can cause our bodies to take a little bit of time to regulate our heat in our bodies. So that inability to regulate temperature is often linked with longer periods. It can be linked with some more pain.

We see it in the other way around as well with menopause, when the hormone levels are fluctuating, the temperature balance can go off-kilter. And so it seems that for some women, it can happen the other way around. That's when the temperature goes off-kilter and the hormone levels are affected.

3. Stress

However, I think the biggest thing that is affecting PMS and probably, period pain as well during very hot weather is stress. So, our bodies aren't used to this kind of heat unless this is what you are used to. You know, if we live in UK and Ireland, our bodies aren't used to this kind of intense, intense heat! And that can put stress on our bodies.

So, you know, there's obviously the sort of emotional stress of being in the hot weather when we're not used to it, maybe getting sunburned and worrying about that or whatever other stresses there might be, but the physical stress on our body as well is a big one when it's very hot.

When we're stressed, our body produces more of a hormone called cortisol. You've probably heard of it. And cortisol then puts our estrogen and progesterone levels off-balance a little bit. So, what it actually does is: an increase in cortisol will decrease our progesterone levels. Our progesterone is our calming hormone that kind of comes in the second half of our cycle after we've ovulated.

When we have very low levels of progesterone, which is caused by the increase in cortisol, our estrogen levels are higher. And that's what leads to what's called estrogen dominance or estrogen excess in relation to the progesterone levels. And that really contributes to all the symptoms of PMS, you know, anger, irritability that we talked about already, but also bloating, and breast pain, and tenderness, and headaches, and all the different things that crop up for women.

4. Dehydration

In addition to stress, dehydration is a big factor. Dehydration is also going to put another stress on our bodies. But being dehydrated is going to significantly worsen PMS symptoms as well as period pain. Dehydration is really, really common in the heat because we're not used to drinking so much.

We wait till we're thirsty and then it's actually a rehydration process, so trying to catch up on your dehydration. Trying to catch up on your hydration after you've already become dehydrated is kind of like running uphill, which you definitely want to avoid in this heat! So instead, make sure you're drinking a lot of water in advance.

A formula that I share a lot to know how much water to drink is multiplying your body weight in kg multiplied by 0.033 and that's going to help you figure out how much water you need to drink on a daily basis. If you drink coffee or alcohol, you need to add an extra glass of water on top of that amount. And if it's hot, especially if you're sweating, then you also need to have more water again. Again, you know, it depends on yourself.

A good way to check is to have a look in the toilet after you do wee. If your urine is in any way dark or not sort of a just nice, pale yellow colour, then it's a sign that you really need to drink a bit more.

Dehydration can also worsen other PMS symptoms then, and so can the heat. So dehydration can also affect things, make your headaches worse, of course, and it can also make bloating worse. But even if you're staying hydrated, the heat can worsen those symptoms or headaches. You can get heat and the headaches for different reasons than you get heat when you're dehydrated. The blood vessels actually contract when you're dehydrated, but they expand when you're in really hot weather. So that kind of expansion and contraction of the blood vessels can cause you to have headaches.

The heat can contribute to bloating. Sometimes, people think when they're bloated that they don't need to drink more water. You know, more water would make them more bloated. But actually, drinking more water is going to help with the bloating even though you feel puffy and full. Whether it's bloating in your belly, or maybe, swelling and tenderness in your breasts, or maybe swelling in your ankles, all of these things are actually helped by drinking more water. So get that water into you!

5. Sleep

The last thing I want to talk about is sleep. Sleep is so important for our overall health and healing. But particularly, if we chronically undersleep, if we're not getting, seven to eight hours of sleep and some of us even need more than that every night, then our bodies are playing catch up, and they're not going to do the healing that they need.

So that can contribute to symptoms of PMS, and a whole range of other things. But, of course, as we know, as we've probably experienced recently, it's really hard for us to sleep in the really, really hot weather when we're not used to it. So that's another cause that can make that PMS worse is if we're not getting enough sleep.

So good things to do are just to try and stay as cool as possible at night. Keep your windows open. Drink lots of water to avoid dehydration, to minimize headaches and bloating. And stay cool when you can. Another good thing to do is to eat lots of fruit that is filled and vegetables that are filled with water, so things like cucumbers, and watermelons, and other types of melons, and fruits. They have got a high content of water in them as well, so that's going to help keep us cool.

Try Agnus castus to ease symptoms of PMS

And lastly, if you do suffer with symptoms of PMS on a regular basis and they're just getting worse in the heat, and you haven't tried it yet, definitely try our wonderful herb Agnus castus. Agnus castus is one of my favourite herbs!

For women, it's brilliant at balancing all sorts of different symptoms related to PMS. It helps our hormones to communicate better together and helps to bring down that excess of estrogen and increase our progesterone levels so it helps to kind of balance everything out and get us feeling more ourselves for more of a month.

Agnus castus | Helps Relieve Pre-Menstrual Symptoms | Mood Swings, Menstrual Cramps, Bloating & Breast Tenderness

£10.85 (50ml) In Stock Get it tomorrow, 13th August.

So, if you have any questions, as always, please let me know. You can send me an email or comment here on the blogs, and I will get back to you as soon as I can. And if there's any other topics you'd like me to cover in the future, please let me know. I'm wishing you all lots of fun in the sun. Stay hydrated and have a great time!


Lastly, if you're on Instagram, follow my new page @SiobhanTalksPeriods for great positive period content and add it to your favourites so you never miss a post!

Agnus castus | Helps Relieve Pre-Menstrual Symptoms | Mood Swings, Menstrual Cramps, Bloating & Breast Tenderness


£ 10.85

Buy now

A traditional herbal remedy used to relieve the symptoms of PMS
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