Now, thanks to science, we finally have the answer.
Advanced accredited practicing dietician Melanie McGrice has penned a blog post detailing alllll the different avenues researchers have explored trying to solve this tasty conundrum.
She explains that most people put it down to the hormonal imbalances that occur during the menstrual cycle - that the reduction in levels of estrogen, progesterone and the feel-good hormone (serotonin) paired with the increase of cortisol (the stress hormone) results in sugar cravings.
In short: we eat it to make ourselves feel better.
But Melanie wasn’t convinced by this idea.
Instead, she looked to a 2004 study that compared the chocolate cravings of Spanish and American women. Researchers found that the latter were far more likely to chow down on the brown stuff during their time of the month, suggesting that it’s actually a learned behaviour.
“I believe that craving chocolate before our period is a mixture of physiology, psychology and cultural conditioning,” she writes.
“Our hormonal changes during the days leading up to your menstrual cycle leave us feeling stressed and tired, which we try to eradicate by indulging in our favourite comfort foods.”
“This ends up creating a cycle by which we crave high fat and sugar foods when we get our period every month.”
This article originally appeared on Women's Health.