Prevent period pain by drinking more water

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Prevent period pain by drinking more water



  • Key finding: Study shows that drinking 8.5 cups of water daily reduces menstrual cramp pain and shortens the length of menstrual bleeding compared to drinking 7 cups or less.

FEBRARY 23, 2021—Do you experience menstrual cramps most cycles and wish there was an easy way to prevent the stabbing, aching, throbbing pain? Simply drinking more water throughout the day may be the solution. Sound too easy to work? Read on….

Study investigates cramp/H2O link

In a 2021 study published in the journal BMC Women’s Health, researchers recruited 140 women ages 18 to 30 who regularly experienced menstrual cramps and who also typically drank around 7 cups (1.6 liters) or less of water per day.1 That’s about one cup less than the daily recommended amount.

They then divided the women into two groups:

  • 70 women were asked to continue drinking their typical everyday amount of water (the control group)
  • 70 women were asked to increase their water intake to 8.5 cups (2 liters) of water per day (the experiment group)

The study volunteers in both groups were asked to follow this water protocol for two menstrual cycles in a row.

What the researchers found

After just one menstrual cycle, the women who increased their water intake to 8.5 cups daily reported that they experienced significantly less menstrual cramp pain on Day 1, Day 2 and Day 3 of their periods than women who continued to drink just 7 cups or less.

In fact, the number of women who didn’t need to take any pain relievers for cramping increased from 7 to 28–a 300% difference.

By the second menstrual cycle, the intensity of period-related uterine aches dropped even lower in the 8-cup-a-day water drinkers.

Compare that to no change found in the control group who drank less.

The science behind water’s pain-killing effect

What makes water so effective at preventing period cramps? As the researchers explain in their study, even a “slight” shortfall of your daily recommended 8 cups of H2O is enough to lead to a rapid release of vasopressin, a hormone that contributes to uterine contractions behind your painful period cramps.

Vasopressin also constricts blood vessels, which reduces blood flow to the uterus, exacerbating pain by causing muscle tension.

The takeaway

While 8 cups of water daily has been only a rough estimate of how much water the body needs, this study shows that staying hydrated is one component of menstrual health.

If you’re athletic, spend time in hot or humid conditions, you may need to up your intake of H2O a little more. You may also need extra fluids if you’ve been drinking alcohol, have had diarrhea or been vomiting, of you’ve been sweating due to a fever.

But, no matter how much you drink, space out your fluid intake throughout the day. Drinking too much at once can throw your body out balance and actually lead to health issues.

If you need help remembering to drink up or figuring how much you drink, keep a water bottle within reach and measure how much it holds. Then, simply count how many refills you make.

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(1) Behnaz Torkan, et al., “The role of water intake in the severity of pain and menstrual distress among females suffering from primary dysmenorrhea: a semi-experimental study”, BMC Women’s Health, 21 (2021): 40

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