Period bloating: why it happens and how to feel less puffy

Period bloating is real water retention driven by the progesterone-to-estrogen shift in the late luteal phase. Three to five pounds of water weight that disappears within days of your period starting. It is not fat gain. It is not failure. It is hormones doing what hormones do.

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Why it happens

Progesterone slows GI motility (so things back up). Falling estrogen causes water retention. The bloating peaks 1 to 2 days before bleeding starts and resolves over the first 2 to 3 days of the period as hormones reset.

What actually reduces it

Less sodium the week before (skip processed food, restaurant food, soy sauce, deli meat). More water (counterintuitive but real - dehydration makes you retain more). Magnesium glycinate. Walking. Potassium-rich foods (banana, avocado, sweet potato).

Stop weighing yourself this week

You are not gaining 3 pounds of fat in 4 days. That is water. The scale lies in the luteal phase. Hide it.

When it is not bloating

Persistent bloating that does not resolve after your period, pain with bloating, unexplained weight loss, or change in bowel habits - that needs a doctor. Ovarian issues and IBS-like conditions can present as "just bloating."

Common questions

How much weight do you gain from period bloating? +

3 to 5 pounds of water in most women. Some gain more or less. It clears within 2 to 5 days of bleeding starting.

Does drinking more water reduce bloating? +

Yes. Dehydration triggers more water retention. 9+ cups of water per day, more if you are caffeinated or in heat.

Will a low-carb diet stop period bloating? +

It might reduce some water retention but is not necessary. Less sodium and processed food do more, with less life disruption.