How I Lost Weight With Intermittent Fasting According To My Cycle

Here’s the refresher course for anybody who missed it. The basic principle behind intermittent fasting is simple. When glucose levels run low, your body begins to burn fat and your liver begins producing something called ketones. Ketones are restorative, healing tissue in your body and provide energy to your cells which increases your mental clarity.

When you fast longer, you can theoretically continue to increase your benefits. After about 17 hours of fasting, your body goes into autophagy, a process which detoxes the organic materials of your cells. That’s right, all the yucky, man-made chemicals our cells absorb to protect us get shed and your body is able to repair and heal. Longer fasts of 24 or 36 hours can be used to reset your gut and to augment fat-burning.

But there’s a big problem with most intermittent fasting literature. Most fasting advocates operate under the assumption that men and women can fast according to the same routines, and that the longer the fast, the better it is for your body. This is a problem because men and women have completely different hormonal cycles, and fasting like a man can wreak havoc on a woman's fertility and hormones. 

Even after I read about the benefits of fasting, I was still a skeptic. It wasn’t until I found a routine of fasting that takes a woman’s hormones into account that I decided to give intermittent fasting a try – and the results I experienced made it well worth the search.

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What Does It Mean To Fast According to Your Cycle?

That’s where the work of Dr. Mindy Pelz comes in. In her book Fast Like a Girl, Dr. Pelz describes an intermittent fasting routine which varies according to a woman’s hormonal cycle. “Men are hormonally simpler,” Dr. Pelz explains in her chapter on fasting like a girl. “They have a 24-hour hormone cycle with one main hormone. … Men don’t have the ebbs and flows of estrogen and progesterone to contend with.” Because women are hormonally more complex, women who choose to fast need to do so in accordance with the hormones that their body is producing.

So, what is fasting according to your cycle? Basically, your body needs different things from you depending on the phase of the cycle you’re in. Sometimes, it’s ready to kick into autophagy and clean out your cells; other times, it needs some tender loving care. There’s a way to experience the benefits of fasting without punishing your body and ultimately harming your hormonal health. Here are the basic phases your body goes through and how to fast during each one.

Power Phases

This occurs twice during your cycle, roughly from Day 1 to 10 and then again from Day 16 to 19, or immediately after you ovulate. During a power phase, your body produces a growing amount of estrogen, and estrogen loves it when your insulin levels are low. Longer fasts put your body into ketosis and autophagy, lowering your glucose and insulin levels. During these phases, you can fast anywhere from 13-72 hours. These periods of longer fasting should then be accompanied with lower glucose foods that will not spike your insulin levels and plenty of healthy fats like MCT oil.

Manifestation Phase

This phase occurs when you are ovulating, typically from Day 11 to 15 of your cycle. During this time, your estrogen will peak, and you’ll experience a minor surge in testosterone and progesterone as well. It's a great hormonal space to be in, and you probably feel incredible during these days. But because your body is coursing with high hormone levels, your body needs to focus on metabolizing those hormones. This phase calls for shorter fasts – nothing longer than 15 hours – and for a focus on foods that nourish your detoxifying organs such as your liver and your gut.

Nurture Phase

No fasting – and yes, you heard me right. From approximately Day 20 of your cycle until your menstrual cycle begins, your body needs to preserve its progesterone (that calming hormone we all want more of). If you fast during this phase, you risk spiking cortisol (the stress hormone) and throwing off the delicate balance of your body, which is preparing to start the whole cycle again. During this phase, Pelz recommends no fasting at all (which isn’t the same thing as over-eating – don’t do that either!) and eating more healthy glucose-producing foods to help make more progesterone.

Resources and Tricks That Helped Me Fast Successfully

Track Your Cycle

If you don’t do this already, stop reading this article and go start tracking your cycle now. As a woman, it’s crucial that you know where in your cycle you are and which hormones your body is producing. There are several apps that you can use to track your cycle, but my favorite is 28 Wellness. Not only does this app have a helpful calendar reminding you which phase you’re in, but it offers exercises, recipes, and meditations which are helpful for each phase. Using 28 Wellness, I was actually able to observe my cycle becoming more regulated once I started fasting like a girl.

Hydrate, Hydrate, Hydrate

Find a good water bottle that will keep your water cold and keep it close to you at all times. It’s shocking how often we develop the habit of eating when all our bodies really want is just a drink of refreshing water. When I first started fasting, I thought drinking water would somehow “trick” my body when I got hungry. But I quickly learned how often that feeling my body had was actually a desire for water and that I wasn’t really hungry after all. Funny how that works.

Figure Out Your Eating Weakness

Getting into fasting means that, early on, you have to figure out which bad food habits you have. Whether it’s someone who has trouble saying no to chips and salsa with their TV show or someone who skips meals and then binge eats, we often develop unhealthy food habits and fasting can help us break them. For me, that weakness was the evening cocktail. I love the artistry of a mixed drink, and I would often eat food later at night so I could enjoy one. I decided to go dry when I started fasting, and almost immediately, I found eating only within my fasting window to be a cinch. Plus there are other benefits to going dry – check out a few of them here.

Sleep Like Your Life Depends on It

I come from a family of chronically sleep-deprived people. With so much to do in this world of bustle, I never felt like I could afford a decent night’s sleep. But fasting like a girl means taking your hormones seriously, and that also means giving your body the sleep it needs to heal and regenerate every night. Sleep is also linked to your appetite-regulating hormones. Not getting enough sleep increases your level of ghrelin, the hormone that makes you feel hungry, and decreases your level of leptin, the hormone that makes you feel full. Surprise, surprise – fasting is so much easier when you get enough sleep because you’re not pushing your body past its limit. 

Buy High Quality Foods

I can’t over-emphasize this one. I noticed almost immediately that the quality of the food I purchased seriously affected whether or not I got hungry while I was fasting. If I bought brats from Kroger or even ground beef from Whole Foods, I’d be hungry again after only a few hours. When I stocked up on organic ground beef and salmon from my local farmer’s market, however, I found myself feeling full much sooner and for much longer – often making it to an 18 hour fast during a power phase simply because I wasn’t hungry until then. Don’t let the price of high quality foods deter you – I found that I was actually spending less on groceries than I normally do because I was simply eating less.

Closing Thoughts

I’ve always struggled with weight loss, but after six weeks of intermittent fasting according to my cycle, I lost 12 pounds and went down a clothing size. My cycle became more regular, instead of varying by a few days like it had been doing amidst my cortisol-peaking lifestyle. But most importantly, I reset my relationship with food and was no longer being controlled by it.

Intermittent fasting isn’t a cure-all diet program, and it can be dangerous for a woman’s hormonal health unless she fasts according to her cycle. But if you do intermittent fasting according to your cycle, it can help align your whole life to your hormonal cycle as a woman, and ultimately, your femininity.

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