Written by James McIntosh
Reviewed by Sammie Gill
You may notice that bloating is common in the days or weeks before a period.
Making changes to your diet, like cutting back on salty foods and drinking more water, can help, and so can other strategies.
Many women experience premenstrual syndrome (PMS). Bloating can be one symptom, and others may include cramping and changes in mood and appetite.
The type and severity of the symptoms can vary significantly between people. And as with other PMS symptoms, you may experience bloating some months and not others.
In this article, we describe what period bloating is, how to treat it, and why it happens. We also explore other causes of bloating.
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What is period bloating?
Period bloating causes your gut to feel bigger than usual, and it can be uncomfortable or even painful. Your belly may seem swollen, and some people feel like they look pregnant or ‘like a balloon.’
Bloating can be one symptom of PMS, and these symptoms can last from a few days to 2 weeks.
Many women report that their symptoms get worse in the week – and especially the last few days – before their period.
Common symptoms of PMS beyond bloating include:
- cramping and pain
- changes in mood
- difficulty sleeping
- breast tenderness
- changes in appetite
- headaches
- greasy hair
- spots on your skin
7 strategies for treating or preventing period bloating
There are several ways to relieve period bloating and keep it from coming back.
Many of these techniques involve tweaking your diet and daily routine.
1. Cut back on salty foods
Eating a lot of salt can lead to bloating because it causes your body to retain more water.
But you may crave salty foods (and sugary and fatty foods) in the days or weeks before your period.
Highly processed foods contain large amounts of added salt. One way to avoid this salt is to cook from scratch when you can. And when you’re out, it can help to be extra mindful of food choices.
2. Drink more water
Not drinking enough water can lead to constipation. This, in turn, can cause bloating.
Remember that plain water isn’t your only option – many drinks help keep you hydrated. You might opt for milk, kombucha, or fruit or herbal teas.
Some people claim that drinking water eases period bloating by helping the kidneys work better. But so far, there isn’t any research to back this up.
Still, some research suggests that drinking water can relieve other PMS symptoms, including pain. So, be sure to have a hydrating drink nearby, and listen to your body when you feel thirsty.
As a rough guide, the NHS recommends aiming to drink 6–8 cups or glasses of fluid a day.
3. Avoid alcohol and caffeine
Alcohol and caffeine are stimulants that can increase gut motility and the symptoms of bloating.
Both can also increase your risk of having PMS symptoms and retaining water, which can then lead to bloating.
Finding hydrating alternatives to drinks that contain alcohol or caffeine could help reduce your risk of discomfort.
It’s a good idea to limit how much coffee and tea you have throughout the day – or have decaffeinated varieties.
You might opt for a nonalcoholic wine or beer, or a kombucha. If you do drink, you might have a small glass instead of a large one, or a bottle instead of a pint.
4. Make sure you’re getting enough potassium
Potassium is a mineral. Among its many important roles, it helps keep our fluid levels balanced.
So, getting enough potassium can reduce your risk of water retention and bloating.
Potassium-rich foods include:
- avocados
- bananas
- broccoli
- spinach
- Brussels sprouts
- beans and pulses
- nuts and seeds
- fish
- chicken
- turkey
Adults should get around 3,500 milligrams (mg) of potassium a day. For reference, half an avocado contains 360 mg, one banana contains 330 mg and 80 grams of spinach contain 545 mg.
5. Get some exercise
Many doctors recommend regular exercise to relieve PMS symptoms. And research suggests that it specifically helps with bloating.
If you're feeling up for it, aerobic exercise may be a particularly good idea. Examples include brisk walking, running, swimming and cycling.
6. Try supplements
Limited evidence suggests that some supplements could reduce bloating in certain situations.
Probiotic supplements are one example. Probiotics are living microbes that provide health benefits when you consume the right amounts.
Research indicates that probiotics could help relieve bloating by reducing the amount of gas your gut produces. This could also be true for period bloating.
Meanwhile, some people believe that taking higher doses of vitamin D and E might help with PMS symptoms, including bloating. But older research has shown no difference between people who take these supplements and those who don't.
Finally, another older study suggests that vitamin B6 and magnesium could have a positive effect on period bloating.
You can learn more about how to look after your gut health from a doctor.
7. Consider certain medications
Some medications may help relieve period bloating. It’s important to discuss these options with a doctor.
Birth control pills can reduce bloating for some people. However, bloating can also be a side effect.
Doctors can prescribe a type of medicine called diuretics. These help your body get rid of excess fluid. There are also medications that specifically treat bloating.
Your doctor can describe the risks and side effects of these options and advise about whether any would be right for you.
Learn more about how you can relieve bloating here.
Causes
Experts still aren’t entirely sure why period bloating happens.
One possible reason is that changes in levels of hormones (like oestrogen) during the menstrual cycle can alter how the body manages fluids.
This means that the risk of water retention could rise at different stages of the cycle.
Another factor is that your diet may change over the course of your cycle.
As we discuss above, eating more salty, fatty and sugary foods can increase the likelihood of water retention and bloating.
When does period bloating happen in my cycle?
Period bloating and other PMS symptoms develop in the luteal phase of the menstrual cycle.
This begins with the egg travelling to the uterus, and it ends with your period. The luteal phase typically lasts around 2 weeks if your cycles are regular.
PMS symptoms tend to go away within a few days of your period starting.
How long does period bloating last?
Period bloating can last anywhere from a few days to 2 weeks, and the duration can vary from month to month.
Could it be something else?
Bloating is a common symptom of a number of conditions.
Some other causes include:
- irritable bowel syndrome, or IBS
- inflammatory bowel disease, or IBD
- endometriosis
If you have other gut-related symptoms, such as diarrhoea, or if bloating continues after your period, it could point to an underlying condition.
When to see a doctor
If you’re unable to relieve any PMS symptoms and they’re negatively affecting your day-to-day life, consider seeing a doctor about treatment options.
If your bloating doesn’t seem related to your menstrual cycle, or you also have other unexplained digestive symptoms, check with a doctor, who can investigate further.
Summary
Bloating is common before your period. How long it lasts and how it feels can vary from person to person and from month to month.
Period bloating may only last a few days, but it can last up to 2 weeks.
Once you have your period, the bloating should resolve in a few more days.
A number of strategies can help, including cutting back on salty foods and staying hydrated. When bloating is more severe, doctors may prescribe medication.
To learn more about bloating and other gut health topics, visit Symprove’s Gut Hub.
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