Woman holding knee in pain

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When You Hurt, You Really Hurt

Earlier this year, a big study found that when women and men are suffering from the same health conditions—cancer, back problems, infectious diseases—women are significantly more likely to say they're suffering. Researchers from Stanford University concluded that women feel pain more intensely than men, and they said that while tough-guy stereotypes may account for some of the differences, another explanation could have to do with hormones. Previous studies have shown that high levels of estrogen can trigger the brain's natural painkiller system, dampening the "ouch" signals. But when estrogen levels drop during certain parts of the menstrual cycle or after giving birth, the system is thrown off, so women will have a more intense physical response to whatever's ailing them at that time.