Intermittent Fasting for Women

Over the last several years, there has been a lot of buzz around the concept of intermittent fasting (IF) and for good reason.  Many people swear by intermittent fasting to decrease body fat, increase energy and focus, assist in detoxification, keep aging at bay, and even protect them against chronic disease.  In fact, there is evidence to suggest that intermittent fasting can decrease the risk of certain diseases such as type 2 diabetes, cardiovascular disease, and even cancer. 

What is intermittent fasting?

In general, intermittent fasting is a way to manipulate the timing of your food intake to allow for periods of time spent in a fasting state, which requires the body to turn to a different source of fuel – body fat.  Not only that, but during times of fasting, blood glucose is lowered, growth hormone is triggered, hunger regulating hormones like leptin and ghrelin are normalized, detoxification becomes a focus, and the digestive system gets a rest and reset too.  While our current society may find going large amounts of time without food to be against what we know, various cultures throughout history practice fasting regularly because of its amazing mind, body, and health benefits, not to mention our ancestors in the Paleolithic area no doubt went through regular feasts and famines while hunting for food.

How does intermittent fasting work?

There are a few different methods of IF, all of which are effective, so it’s more a matter of individual preference as to how someone incorporates it into their life.

Some examples include:

  • Scheduling one day per week to fast for 24 hours.  The other 6 days have a normal food intake.
  • Schedule alternating days to eat very little (500-600 calories) and the other days have a normal food intake.
  • Scheduling a daily fast of 14-18 hours.  This can be done by skipping breakfast or just condensing all 3 meals into a 6-10 hour window.

My fasting experiment

Because of the popularity of IF and the wide range of positive health benefits, it came as no surprise to me that my doctor would recommend a 2-week IF for me as a therapeutic intervention.  If you’ve been following my battle with mold illness, then you know I have been struggling with leptin resistance due to chronic inflammation accompanied by the illness.  My natural medicine doctor suggested an intermittent fasting schedule to help regulate and reset leptin, the hormone responsible for metabolic management and hunger cues.  I chose the 16/8 method, which means eating 3 meals in an 8-hour window and fasting for 16 hours every day for 14 days, as I felt it was the most gentle option.

I had already been eating a high-fat, low-carb ketogenic diet, so I knew I was adequately fat adapted, plus I had just received my hormone test results so I knew my health status going in to the IF.  I had been dealing with a significant battle with adrenal fatigue and low thyroid function as a result of mold illness as well, so I knew I needed to approach this with caution and monitor those symptoms.  I was ready to jump in!

The first few days were pretty brutal.  I was waking up hungry at night and dying to eat breakfast in the morning hours before my fast was over.  I put coconut oil in my tea to help ease the hunger.  But, then at around day 4, something drastic shifted.  I was NOT hungry.  So much so, that some days I actually forgot to eat breakfast until almost 11:30am!  And my meals within that 8 hours were getting smaller yet more nutrient-dense.  Since I wasn’t hungry, I was only eating the foods that would actually provide the energy and nutrients I needed without extra bulk.  This meant lots of FAT and leafy green vegetables.  Bacon, eggs, ghee, coconut, avocado, raw, grass-fed cheese, coconut oil, and fatty cuts of meat.  This got me into an even deeper state of being fat fueled and meant even less hunger.  It was SO freeing!  I suddenly wasn’t thinking about food all day, packing snacks when I was away from home, or eating a treat before bed.

I enjoyed my times of fasting as well because I wasn’t thinking about food.  I would wake up early and get a bunch of work done, then focus on breakfast as a midday break.  I was clear-headed and energized even without the normal ‘food jumpstart’.  These quickly became the most productive hours of the day.

I made my way through the 2 weeks and am currently awaiting the results of my updated labs.  Without knowing the exact changes that occurred, I feel confident that they will all be in the positive direction — even my thyroid and adrenal markers, based upon the positive changes in my symptoms.  Because of this, I am continuing on with daily fasts even now that my 2-week experiment has officially ended.

Intermittent fasting and women

Intermittent fasting has gotten a bit of a bad rap as it relates to women, more specifically, the effects of IF on female hormones.  There are reports of women who tried IF and lost their period, went into early menopause, or had raging PMS after starting intermittent fasting.  However, there are also women who swear by IF, crediting it for stabilizing their mood swings, jump starting weight loss, and clearing brain fog.

Scientific data is minimal on the subject.  The few studies that are available show that while men have really positive results with intermittent fasting, women’s results are mixed. One study conducted the trial on female rats and was able to conclude that intermittent fasting negatively impacted reproduction capability.  However, another study done on humans found that intermittent fasting helped women lose weight and improve their metabolic and lipid markers.

I think it’s safe to say that, just like every other dietary and lifestyle change, intermittent fasting is a very individualized concept no matter your gender.  In my opinion, intermittent fasting can still be a very effective tool in your toolbox as long as extra caution and specific guidelines are met to ensure its safety.  If IF is something that resonates with you, I’ve developed a list of do’s and don’ts to keep in mind during your trial.


Do’s and Don’ts of Intermittent Fasting for Women

Do keep tabs on your hormone health.

The biggest risk women have with intermittent fasting is with their hormones.  Our hormones play a very delicate balancing act on a repeated 28-day cycle (on average).  Sometimes the slightest change in our diet, health, mindset, environment, toxin exposure, or stress-level can cause hormonal imbalance to occur leading to further health issues down the road.  If not done properly, intermittent fasting could easily become one of these triggers for hormonal imbalance because of the stress it can cause on your body.

It’s not only the sex hormones that can be affected.  Cortisol and thyroid hormones are also very important to monitor, especially if you have had past issues with thyroid disorders or adrenal fatigue.

Following the steps listed below will help tremendously in keeping your hormones balanced and stress level regulated.  It is also very important to check on the state of your hormones before you even begin.  If you are already dealing with a hormonal imbalance of any kind, addressing that issue will need to precede the intermittent fasting plan.  The best way to do this is to test both your daily cortisol rhythm and your monthly hormonal cycle with a salivary collection.

Don’t diet.

Ok, are you ready for the biggest reason why intermittent fasting DOESN’T work for women?  Because we also try to diet at the same time!  This is not the concept behind intermittent fasting and will ultimately either lead to bingeing, failure, or health and hormonal issues.  During the period of time you are eating, you need to EAT.  Eat a lot of really nutrient-dense, calorically-dense foods in that timeframe and do not try to be in a huge calorie deficit.  This won’t work.  I like to think of intermittent fasting as a better, safer, smarter option to restricting calories.  But, definitely never do both.

Do focus on fats.

In order to make sure you’re not going into too big of a calorie deficit, your diet will need to consist primarily of healthy, nutrient-dense fats.  These include fat from properly raised animals, unsweetened coconut and coconut oil, nuts and nut butters, pasture-raised butter or ghee, eggs, avocado and avocado oil, olives and olive oil, and grass-fed dairy products.  When these foods become staples, you can rest assured that you will be getting enough nutrients and calories in your day prior to fasting.

Not only that, but switching to a high-fat diet will also ensure your fasting periods are stress-free, safe, and comfortable.  With the reduction of carbohydrates and inclusion of a large amount of fat, your blood sugar will become extremely stable.  Instead of being a rollercoaster (which is what happens to our blood sugar when we have excess carbohydrates in our diet), it will be more like small waves.  When our bodies are on the rollercoaster route, there will be a dip in blood sugar a few hours after your last meal, which brings on feelings of hunger.  When no glucose is provided by way of a meal, cortisol – our stress hormone – will come to the rescue.  So, now you’re hungry, you’re still fasting for another 5 hours, and your body senses a stressful event.  Not good!

However, when you take a high-fat diet approach and become fat-adapted, that dip in blood sugar doesn’t happen and the stressor isn’t there because your body no longer relies on only glucose for energy.  Your body has learned to run on fats – both dietary and stored body fat – instead of just waiting for the next meal.  Now, not only are you not having feelings of hunger, but you’re eliminating the stressful event!  And, as we discussed above, the reason why intermittent fasting can be hard for women is because of the hormonal imbalance that can develop from the stress and cortisol response.  Just by eating high-fat and plenty of food, we have eliminated that stressor!

Don’t workout intensely.

At least for the first week or two until you know how intermittent will affect you.  Once your body becomes adapted to this change, chances are workouts will actually feel better in the fasted state and you will begin to see improvements in your workouts.  But, first you need to eliminate all added stressors while your body adapts and gets used to this new energy source (fat). Taking walks in nature or a really great yoga class will be the best way to get movement in during this transition time.  After that, begin incorporating short HIIT sessions like jumping rope, sprinting, or heavy lifts in the gym and see how you feel.  Remember, the end goal is to keep the stress level in the body at an all time low, thereby keeping your hormones in balance.  Working out too intensely while your body is shifting energy sources will likely cause stress.

Don’t make fat loss your main goal. 

There are many success stories out there of people who have had complete body composition changes just by incorporating intermittent fasting.  And it’s true. It is a great tool for losing weight, getting leaner, and decreasing body fat.  BUT, I don’t think any female should do it just for that purpose.  This is not the next way to obsess about your body and try to manipulate its size with food.  

This is a therapeutic diet with amazing health benefits and should be viewed as such.  Find a deeper purpose behind your dietary changes.  Do you have brain fog or trouble concentrating? Intermittent fasting is great for brain health.  Want to age well and live longer?  Intermittent fasting has been shown to prolong lifespan and slow down the aging process.  Need to get your blood lipids and cardiovascular markers in check?  Intermittent fasting can bring those markers back in range without the use of medication.

Do start slow.

Intermittent fasting isn’t something you need to dive into all or nothing for it to be effective.  In fact, women may have better luck with easing their way into it.  Spend 3-4 weeks becoming fat-adapted with a high fat diet first.  Then, add in an intermittent fasting schedule a few days per week.  For instance, try doing a 16/8 fast on Mondays and Thursdays and see how that feels.  If you enjoy it, add in more days as you feel comfortable.

Don’t continue if you feel bad.

This should go without saying, but obviously if you are feeling weak, tired, dizzy, or just don’t like it, then don’t do it!  This is not something that will feel right for everyone, so pay attention, listen to your body, and always do what’s right for you.

Do enlist the support of a professional.

As with any advice I give, I always recommend seeking the help of a professional to guide you through the changes you wish to make and support you along the way.  This will make it easier to acknowledge what is right for YOU instead of just guessing.


About the Author:

Shawn Mynar is a holistic health practitioner and nutritionist out of Boulder, Colorado. After healing herself from chronic illness which included two autoimmune diseases, toxic mold exposure, severe adrenal fatigue, and leaky gut, with a high-fat, real food diet, Shawn’s passion now lies in helping others do the same. She uses functional testing in her private practice to get to the root cause of her client’s health issues and, from there, uses the power of food as medicine to address hormonal imbalance, gut health issues, adrenal fatigue, thyroid dysfunction, weight loss resistance, and more. In her free time, Shawn enjoys dancing, yoga, Netflix binges, anything having to do with bacon, kombucha, and reading in coffee shops. Find more about her at

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