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Hormones

How Hormones Affect Your Attitude

Whether we like it or loathe it, our hormones wield a lot of power over our bodies. They can make you feel calm and more confident or edgy and self-doubting, and that affects how you handle any situation -- whether you freak out when your boss gives you a last-minute project, for instance, or find the willpower to resist a second piece of chocolate cake. "The ups and downs of estrogen, progesterone, and testosterone influence your behavior throughout the month," explains Scott Haltzman, MD, clinical assistant professor of psychiatry and human behavior at Brown University.

Because so many of us are confused about how our hormones affect us on a daily basis, FITNESS asked top experts to demystify these fluctuations -- and explain how you can use hormonal shifts to your advantage. Here, an updated guide to timing life by your cycle.