Is PMS a Myth?

New research says yes.

Guys, you may blame ladies’ hot and cold moods on “that time of the month,” but new research suggests premenstrual syndrome (PMS) doesn’t even exist.

In other words, ladies, apparently those food cravings and mood swings that pop up once a month are all in our heads.

A group of researchers at the University of Toronto say that after analyzing 41 studies that tracked women’s moods throughout their menstrual cycles, there is no clear evidence that PMS is real.

“Our review—which shows no clear evidence that PMS exists—will be surprising to many people, including health professionals,” said professor Gillian Einstein in a statement.

Surprising, indeed. The researchers found that only six (13.5 percent) of the studies found an association between negative mood and premenstrual phase. In addition, they said many of the studies were biased, since both women and men have been taught since puberty that PMS exists.

The researchers acknowledged the existence of the actual physical symptoms women experience during their period—headaches, tender breasts, cramps, temporary weight gain, and fatigue—do occur during menstrual cycles. They also recognize the existence of premenstrual dysphoric disorder (PMDD), which is a more severe form of PMS that occurs during the second half of the menstrual cycle.

The researchers hope their findings will discourage the negative thoughts typically associated with female reproduction; when a female is upset people shouldn’t automatically wonder if she’s on her period, they said. “These studies failed to provide clear evidence in support of the existence of a specific premenstrual negative mood syndrome in the general population,” they wrote. “This puzzling widespread belief needs challenging, as it perpetuates negative concepts linking female reproduction with negative emotionality.”

The full study was published in the journal Gender Medicine.