Breakfast is the only kind of fast that works for my body, personally. I am definitely someone who gets hangry really easily, and whenever my blood sugar levels start to drop, I just don't feel like I'm functioning at my best. I have friends who swear by keeping to a pretty specific eating schedule during the day, such as intermittent fasting. The thing is, though, I can't help but wonder, if you're going through such long periods of time without eating, can intermittent fasting affect your period? What does this type of eating schedule really do to your body beneath the surface?
In case you hear the term "intermittent fasting" and it only brings to mind long, uncomfortable spans of time of going hungry, here's a little refresher on this way of eating. Basically, as per Healthline, intermittent fasting means having designated times during which you eat all of your food for the day, as well as designated times when you give your body a rest from eating and digesting. The specific lengths of time can vary with each individual person, but as Healthline notes, the "fasting" part of the day is often during the time a person spends sleeping, and "intermittent fasting can be as simple as extending that fast a little longer." In other words, you're already not eating when you sleep between, say, 11 p.m. and 7 a.m., so the fasting part of the day could just be those first few hours of the morning after you wake up, if that works for your body and your appetite.
While intermittent fasting doesn't necessarily lead to period problems, experts say you should be extra careful to listen to your body's cues when it comes to this way of eating.
"Human menstrual and reproductive functions are controlled primarily by the hypothalamus and pituitary glands and their input to the reproductive organs (e.g. ovaries and uterus)," Dr. Joshua Klein, chief medical officer and reproductive endocrinologist at Extend Fertility, tells Elite Daily in an email. "The function of the hypothalamus and pituitary are very much influenced by nutrition, metabolism, and energy availability," he adds, and any disruption of these systems could potentially lead to menstruation problems. That being said, Dr. Klein explains, there is little data to predict how intermittent fasting will affect your period, so it's probably wise to make that decision with your personal doctor.
"Intermittent fasting alone shouldn’t cause amenorrhea (aka stopping of a woman’s period)," says holistic health coach Erin Wathen. "Intermittent fasting isn’t supposed to be about going super low calorie where a woman’s period would stop, but [rather] reducing the individual's eating window." In other words, if you're being careful to follow an intermittent fasting plan to focus on your health, not on restriction, then your period shouldn't be affected. "Intermittent fasting is intended to give our bodies and mind a break from always eating, not as a means of extreme weight loss," Wathen tells Elite Daily. "Often it is used like a diet, which isn’t the intention."
If you're new to intermittent fasting, then you may find yourself having trouble eating enough in that shorter time window, so make sure you're getting plenty of nutrients during the time that you do eat. Of course, says Wathen, if your period does stop at any point, you should get in touch with your doctor to figure out what's going on ASAP. In addition to seeking professional help, if you haven't been getting your period, Wathen suggests switching to a gentler exercise plan and adding in some sources of healthy fat to your meals — specifically, she recommends avocados, coconuts, and almonds.
Overall, you should definitely be extra careful about listening to your body when it comes to intermittent fasting, says Kathleen Meehan MS, RD, LDN, a non-diet dietitian based in Houston, Texas. "One specific concern I'd have about intermittent fasting is that it often leads to low energy eating," she tells Elite Daily in an email. "Low energy eating often leads to health concerns, including missed periods. One of the reasons I don't recommend intermittent fasting is that it encourages people to ignore their body's cues, which is not health promoting."
If you aren't eating enough, it's possible that you could develop something called hypothalamic amenorrhea, says Meehan, which happens when the body doesn't have enough energy to have a period. "Our bodies need food, and adequate amounts of food, to function. If a body doesn't take in enough calories to support its energy needs, it's entirely possibly that the reproductive system suffers and women can lose their periods," she explains.
For anyone who's having a hard time eating enough with intermittent fasting, Rachel Fine, a registered dietitian and owner of the nutrition counseling firm To The Pointe Nutrition, suggests making the majority of your fasting hours take place at night, rather than during the day. "This should align with our body’s natural circadian rhythm," she tells Elite Daily. "In order to maintain optimal blood sugar levels and efficient metabolic functioning, one shouldn’t go longer than 12 hours without eating."