Although annoying, cravings are at least predictible—when it's that time of the month, and you see a raging pimple pop up, you know you're going to inhale that emergency chocolate stash like there's no tomorrow.
What's more mysterious is that insatiable hunger that can arise right before and during your period. So if you're wondering why the triple-stacked turkey sandwich you had for lunch didn't even begin to fill you up, don't worry: That lurking hunger is totally normal, and actually comes down to our primal instinct.
The Hunger Games
During ovulation (around 12 to 16 days before your period), your body is getting ready for a potential pregnancy, says Jamé Heskett, M.D., author of The Well Path. It wants to be stocked and ready just in case, so the hormones that peak during that time—estrogen and progesterone—trigger a hunger response, telling you to get some food (yep, your body sounds a lot like a Jewish grandma). Energy and nutrient intakes during different phases of the menstrual cycle in females in the United Arab Emirates. Cheikh Ismail LI, Al-Hourani H, Lightowler HJ. Annals of nutrition & metabolism, 2009, Mar.;54(2):1421-9697. Energy intakes are higher during the luteal phase of ovulatory menstrual cycles. Barr SI, Janelle KC, Prior JC. The American journal of clinical nutrition, 1995, Feb.;61(1):0002-9165. Modest changes in dietary intake across the menstrual cycle: implications for food intake research. Bryant M, Truesdale KP, Dye L. The British journal of nutrition, 2007, Jan.;96(5):0007-1145.
On top of that, your body's basal metabolic rate speeds up just before and during the early part of your period to fuel the process of menstruation, says Gerardo Bustillo, M.D., an OB/GYN at Orange Coast Memorial Medical Center. Menstrual cycle and basal metabolic rate in women. Solomon SJ, Kurzer MS, Calloway DH. The American journal of clinical nutrition, 1982, Dec.;36(4):0002-9165. Up to 15 percent more calories are burned (around 100 to 300 calories more per day), which can also make you feel hungrier.
All this means that constant eating was a fantastic instinct during evolutionary times for the perpetuation of the human race—sink or snack, basically. Loading up on high-calorie food is helpful when your brain is in survival mode, because high-calorie ostensibly means more nutrients, Heskett says. (Our bodies can't tell it's McDonald's.)
But alas, our bodies also don't know about Seamless. Today we can find food basically anytime, anywhere, but the body still sends signals to eat (and eat, and eat) whenever possible, even if we know we shouldn't be hungry.
Frustratingly, this hormonal hunger can also be a reaction to us denying ourselves food. If we anticipate saying no to the good stuff because we know we're going to be illogically hungry, the body actually makes the hunger instinct even stronger, Heskett says. Again, eating more in the face of coming deprivation was a smart evolutionary habit—but now we're seeking out chicken wings for no reason.
Fluctuations in estrogen and progesterone levels can also affect neurotransmitters like serotonin, which plays a big role in mood swings and food cravings, Bustillo says. When serotonin levels hit a low right before your period, eating sugar- and carb-laden "comfort foods" (think lasagna or doughnuts) will spike serotonin and dopamine levels in the brain, boosting your mood and making you feel better—for the time being. Chronic stress and obesity: A new view of “comfort food.” Dallman, et al. Proceedings of the National Academy of Sciences of the United States of America. 2003 Sep 30; 100(20): 11696–11701. (In the long term, overeating these simple carbs can lead to obesity, diabetes, and other health issues. Effects of dietary glycaemic index on adiposity, glucose homoeostasis, and plasma lipids in animals. Pawlak DB, Kushner JA, Ludwig DS. Lancet (London, England), 2004, Sep.;364(9436):1474-547X. )
If you have disturbed sleeping (pulling all-nighters or only getting six hours a night), that can make it even worse, adds Iffath Hoskins, M.D., an obstetrician at NYU's Langone Medical Center and Greatist expert. As can your genes—it turns out that the extent to which you're inclined to emotionally eat around your period can come down to your DNA.
While all women may experience this progesterone- and estrogen-fueled hunger, women with genetic risks for eating disorders are more vulnerable to "emotional" or "binge" eating during their menstrual cycle, when it feels impossible to stop, says Kelly Klump, Ph.D., a Michigan State University Foundation Endowed Professor who studies eating disorders.
"These hormones actually turn genes on and off," Klump says. So when there's an increase in the hormones after ovulation, risk genes for eating disorders are more likely to be activated—meaning while you may normally feel in control, your risk of ED-prone behavior spikes when your hormones are all over the place.
This susceptibility can create a vicious cycle, especially because Klump's recent research has found that women become increasingly preoccupied by their weight post ovulation. Changes in genetic risk for emotional eating across the menstrual cycle: a longitudinal study. Klump KL, Hildebrandt BA, O'Connor SM. Psychological medicine, 2015, Jul.;45(15):1469-8978. It's a kind of reaction to binge-eating, she says—after our bodies tell us to overconsume calories, we're left with concerns about our body weight and shape. (Come on, Mother Nature!)
Your Action Plan
First, load up on iron-rich foods pre-period stage, Heskett suggests. Foods like red meat, fish, and leafy greens can help replace the iron that you're losing right before and during your period. This will create a "feedback loop" to the body, telling it that you are actually responding to it in a way that it needs, Heskett explains.
In the long term, this will help us stay tuned in to what our body's asking for (Oreos—not the answer). And if you're dealing with what feels like unassailable hunger but know that you ate only an hour ago, Heskett says to try waiting 20 minutes before eating again—the hunger may pass. If it doesn't, don't deprive yourself, but grab a healthy snack instead.
Also key: Be mindful about what your hormones are up to, Heskett says. If you know you're prone to binge-eating, tracking your cycle can give you back some power over what may feel like eating out of the blue. Sure, you can still buy that box of dark chocolate (for the joy, for the antioxidants), but keep in mind that it may invite binging if you're prone to it. Practice portion control, or invite some friends over and split it with them instead.
Thanks to a dual bump in progesterone and estrogen, hormonal eating hits an all-month high right before your period. And it doesn't always look like "typical" cravings—it can just be a constant urge to snack, which is your body's way of getting nutrients in case you might be pregnant. Genetic factors and trying to cut yourself off altogether can make it worse, so if you notice you're constantly hovering in the kitchen, try to have an iron-rich snack or just let it pass.