Sudden period weight gain? Why + what helps

period weight gain

Men can roll their eyes all they want at the range of sizes in our closets. But weight gain of up to five pounds around your period is completely common. Let’s look at your cycle to find out what’s happening with your hormones before your period and why that can add a few extra pounds to the scale.

What’s happening in your menstrual cycle

Many of us have been trained to think a new menstrual cycle starts after you stop your period. But, really, the day you start your period is day 1 of a new cycle.

An average menstrual cycle has a few phases: follicular, ovulation, and luteal. Your follicular phase starts on the first day of bleeding. (Remember: this is day 1 of your cycle.) As your body works its way toward ovulation, follicles begin to develop on the ovaries. These follicles have young eggs. Most die off, but one develops. Around day 14, higher levels of certain hormones make you ovulate, or release the egg that developed.

In your luteal phase, or the phase before your period, progesterone levels build up. If you don’t get pregnant, those levels drop and you get your period.

How your cycle affects your weight

Between ovulation and your luteal phase, lots of hormone changes are happening and these hormones can make you gain weight or water weight.

Problem 1: electrolyte changes

Woman feeling bloated from PMS

We think of estrogen and progesterone as keepers of our reproductive cycles. But they do a lot more than that. The even affect bodily systems that regulate sodium set points and thirst.

What this means is that your cells hold on to more water than usual. We call this added volume “water weight.” It’s not fat gain but it can make a difference in how clothes fit and even what the scale says.

You can get around water weight gain or limit how much it bothers you by doing a few key things. Mostly, think water, water, water. It sounds weird, but making sure you get enough sends a message to your body that it can release that extra fluid from your cells. What also helps is avoiding salty or refined foods (that includes most salad dressings and condiments!). And, if you can cut back on your wine or nightcap, all the better. Alcohol is a recipe for dehydration and even upset stomach… both can make bloat worse.

Problem 2: of course you have the munchies

Feeling hungry or eating more during PMS

Ahhh, progesterone. There are so many reasons to love this hormone. It’s important to sleep, anxiety, and makes your skin glow-y. It even helps your thyroid function. Thyroid hormones play a part in controlling your metabolism, or how your body burns calories for energy.

But there’s one drawback to the increased progesterone that happens before your period. Higher progesterone may make your metabolism speed up a bit. Wait: isn’t that great for weight loss? Yes, it sure is. But there’s a catch-22. A temporarily higher metabolic rate can make you feel hungrier than normal and unconsciously eating way more than you’re used to. Sometimes, that habit can leave you overeating even after your metabolic rate returns normal. (And that’ll pack on some pounds.)

Problem 3: you’re tired, and working out sounds like no fun at all

Weight gain during PMS or with period. Less exercise during PMS

There’s a lot happening in your body before your period. As your body does its thing, your heart rate, respiration, and even electrolytes go for a ride. It can feel like a real chore to work out or even get moving.

Plus, let’s talk progesterone again. Part of the magic of progesterone is that it increases a neurotransmitter called GABA. (GABA is great for sleeping and chilling.) So, with more GABA, you can feel extra tired and may decide to skip your workouts or dial back your activity. Add in how much PMS makes you want to eat, and a little pre-period weight gain can sneak up on you.

So… will the weight drop off after my period?

Ready to throw some confetti? Period weight gain usually drops right back off in a few days or a week. The best way to minimize it or kiss it goodbye: eat well, stay hydrated, and keep up with a little light activity. It’ll help you feel better physically… and also mentally.