In case you didn’t know, fasting puts stress on the body. This is generally a good thing—acute stress shocks the body into autophagy, which is what much of the appeal to fasting is all about. “When you first start fasting and you’re overdoing it, your stress levels go up, but it feels good because adrenaline feels good—until you run out,” notes Asprey. It’s when you experience chronic levels of stress (i.e., overdoing a fast) where people, especially women, may start to see less than favorable effects. Namely, that elevated cortisol can potentially affect your sleep, hormones, and energy levels.
That’s not to say women shouldn’t fast at all—many see amazing results!—but it’s important to notice the signs your body is trying to tell you so you know when to scale back. “Skipping breakfast, having a late lunch, just three times a week. Maybe it’s all you need,” offers Asprey. “Maybe you just do it Monday through Friday, and on the weekends you have the gluten-free waffles with your kids at brunch.” Be kind to your body and its needs.