Your Morning Cup of Jo Could Be Harming Your Period

Whether it’s out of habit or necessity, most of us consume caffeine on a daily basis. But can overdoing it cause our periods harm? Though the research is limited and somewhat conflicting, it seems that the answer is likely yes

Habitual caffeine consumption is classified as 300mg of caffeine, the equivalent of a Grande coffee from Starbucks, and has been linked to elevated estrogen levels. Unsurprisingly, being in a state of hormonal imbalance such as this can cause a myriad of period-related problems.

Here are some of the main ways over-doing your caffeine consumption could be negatively impacting your period: 


Caffeine causes blood vessels to constrict, prompting the muscles in the uterus to contract, meaning more painful cramps. Caffeine also has a diuretic effect, causing you to lose fluid and sodium. This can lead to dehydration, another factor that causes cramping. 

Breast Tenderness

Breasts have small ducts that can swell when exposed to stimulants like caffeine, making them feel heavy and sore. Some women report improvement in breast pain when they cut out caffeine, especially if they have fibrocystic breast tissue.

Uterine Fibroids

Elevated estrogen can promote the growth of uterine fibroids, a type of noncancerous tumour that currently affects up to 40% of women in their reproductive years.


Elevated estrogen is associated with irregular periods, which can make your cycle unpredictable. Signs that your period is irregular include: less than 21 days or more than 35 days between periods, periods where bleeding lasts for more than a week, spotting between periods, and heavy bleeding.

Now for some good news before you swear off your favorite coffee shop - caffeine typically clears out of your body within hours. If you think your period-related problems could be linked to caffeine, try avoiding caffeine leading up to and during your period. It’s important to avoid all caffeine, not just coffee, so steer clear of sodas, dark chocolate, pre-workout powders, energy drinks and pain medications such as Aspirin and Midol which can have hidden caffeine in them. If you’ve cut back on caffeine and are still struggling with period problems like irregularity, consult your doctor. There could be other contributing factors at play.

Written by Laura Jeha

Laura Jeha is Registered Dietician based in Toronto who focuses on plant-centric foods to help people become healthy and happy.