Unique Fasting Needs for Women: Women tend to struggle more with fasting than men, and today we dive into all the reasons why this is true and what you can do about it. Fasting can undoubtedly benefit everyone, but only if you do it in a way that honors your bio-individual needs. You won’t want to miss this information if you’re a woman.

This article has been medically reviewed by Dr. Charles Penick, MD

Fasting in Men Vs. Women

There is no one-size-fits-all philosophy to anything in the realm of health. When it comes to fasting, this is especially true. Although fasting has fantastic health benefits, the key to reaping them is taking a bio-individual approach ^1. Most of the studies on fasting (and studies in general) are done on men ^2. This is because men offer much more predictable results due to their more consistent hormonal patterns.

A woman’s hormones fluctuate in her reproductive years based on a monthly cycle, also called an infradian rhythm ^3. On the other hand, men fluctuate on the daily 24-hour cycle called the circadian rhythm.

Unique Fasting Needs for Women: Cultivating Flexibility

One of the biggest things that impact your success with fasting is flexibility. Flexibility relates to both metabolic flexibility and the general flexibility to let go of rigid, dogmatic approaches to fasting.

Metabolic Flexibility

Metabolic flexibility is your metabolism’s capacity to adapt to stressors and change ^4. Fasting requires metabolic flexibility because going through periods without food forces the body to burn body fat instead of ingested calories for survival. This process is highly beneficial for many reasons but does require a body that knows how to burn fat for fuel.

Many people who experience severe hormonal issues, insulin resistance, or chronic illness may need to train their bodies to become metabolically flexible before they embark on longer fasts. Metabolic flexibility is gained through various approaches, including diet variation, introducing shorter periods of intermittent fasting, cleaning up the diet, reducing toxin exposure, and cellular detox ^5-7.

Routine Flexibility

Another flexibility needed to succeed with fasting is letting go of dogmatic, blanket rules. There is no one-size-fits-all with fasting, and if you ascribe to a hardcore “all or nothing” mentality, you will likely do more harm than good.

This rigidity lends itself to a certain kind of person, who typically over-exercises, is highly disciplined, and tends to see healthy habits with a “more is more” mentality. Unfortunately, when it comes to fasting, that mentality can push you to fast in a way that will cause damage to the body.

When it comes to fasting for women, tailoring your habits to meet your individual needs is even more critical. Due to the cyclical nature of hormones in women, meeting yourself where you are and not comparing yourself to others or even to a past version of yourself will help you get the most out of your fasting routine.

One example of flexibility is knowing when you’ve pushed it too far during a fasting window and either stopping early or introducing some fat into your fasting window. If you’re intermittent fasting, for example, and are feeling more depleted than usual, you may be better off having a spoonful of nut butter before bed to help you sleep. This is especially true for women who are new to fasting.

As you become more metabolically flexible and fat-adapted, you will become more capable of fasting for more extended periods with ease. That said, no matter how much fasting experiences you have, you should always root yourself in the present moment. This is because so many variables can interfere with your resilience to the stress of fasting.

Another example is rigidity around exercise and fasting. Exercise can be beneficial during intermittent fasts (less than 24 hours). During longer fasts, however, you should avoid exercise. This can be difficult for people with very rigid routines who think they absolutely must exercise all the time.

Fasting is a form of stress. It is only beneficial stress if you have the resources to overcome the stress. Less is often more regarding women and the stress of fasting.

In a nutshell: always meet your body where you are. Don’t compare your current fasting period to anyone else’s or a previous fasting period. Instead, tune in, and listen to your body.

Unique Fasting Needs for Women: How to Optimize Fasting for Women

Hormones

In their reproductive years, women’s hormones are much more cyclical than men’s. Although men’s and women’s hormones fluctuate, male hormones revolve on the circadian clock (24 hours) while women operate on a circadian and infradian rhythm (both the 24-hour and 28-day cycles) ^3. The infradian rhythm can also be understood as the menstrual cycle. As a result, women are much more influenced by stress and the various other exogenous factors that interplay with their changing internal hormonal state.

During certain times of the month, women are susceptible to stress. Women’s bodies thrive when their cycles are honored, and the luteal and menstrual phases require more rest and higher calories ^8. Therefore it’s easy to see why introducing fasting during these times (more stress on the body and less to no food) can wreak havoc on the body.

During these more restful phases of the menstrual cycle, women also set the tone for the rest of that menstrual cycle. So, for example, if a woman experiences too much stress (like too much movement or caloric deprivation) during her period, she may experience adverse symptoms for the rest of the month. Although many of these symptoms are considered “normal” these days (like mood swings, low energy, and PMS), they are typically signs of a stress-induced hormonal imbalance ^9.

Women can fast cyclically to honor their menstrual cycle by fasting (either intermittent or a more prolonged fast) during the follicular phase of their menstrual cycle. This is the time after you finish your period and for approximately ten days until ovulation typically occurs. This is the period of the month when women have the most energy and resilience.

Women can also participate in a kind of diet variation where she eats a lower-carb post-menstrual cycle until about a week before their period. Then, upping the carbs and protein during the week before her menstrual cycle and while she bleeds can help regulate her hormones for the whole rest of the month.

Some factors that promote hormonal imbalances in women include: ^8-10

• Chemical stressors (using toxic body care products, perfumes, cleaning products, and the environment)
• Unhealthy foods (highly processed vegetable oils, refined sugars, and flours)
• Snacking all day long
• Emotional stress (staying in long-term relationships that don’t support our mental health)
• Too much screen time, especially at night
• Too much or too little exercise
• Poor sleep quality

Sleep

Fasting is a form of stress, although positive stress still requires a foundation of health and a capacity for recovery to ensure that you don’t do more harm than good 10. Your sleep quality is one of the best benchmarks to check in on to know if you have enough resilience to start fasting.

Sleep quality refers to how many hours you sleep and how deep the sleep is. Sleep quality is measured by how much deep and REM sleep you get. Many wearable tracking devices highlight how much deep and REM sleep you get at night. Without one, you can simply quit caffeine for a week and see how well-rested you feel in the mornings.

If your sleep quality suffers, odds are you are not in a stable enough place health-wise to add the stress of fasting. So address sleep quality first; from there, you can consider adding a fasting routine.

Top tips to optimize sleep quality include: ^11-14

• A regular sleep/ wake time (seven days a week)
• Getting daylight exposure as soon as the sun comes up (at least 10 minutes)
• Avoiding caffeine after midday
• Spend some time with your bare feet on the earth every day
• Avoid eating or exercising too close to bedtime
• Avoid artificial blue light after sundown, and especially 2 hours before bed. Instead, opt for red light or candlelight.
• If exposed to artificial blue light, wear blue light blocking glasses
• Sleep in a cool room or invest in a bed cooling device like the ChiliPad
• Absolutely no electronics or lights in your bedroom at night
• Turn the wi-fi off while you sleep
• Have a nighttime routine that includes a mindfulness practice like mediation
• Some supplements that may support deeper sleep include L -Theanine and Ashwagandha.

Eating Enough

Another factor that makes or breaks fasting for women is eating enough during the non-fasting periods. Whether intermittent fasting or prolonged fasting, it’s essential not to restrict calories during non-fasting periods. If you restrict calories and fast regularly, your body may go into chronic starvation mode, which downregulates metabolism and can cause long-term chronic physical and mental health problems ^15.

If you are fasting, it’s also essential not to chronically be in ketosis. Dietary variation leads to metabolic flexibility, so keep your body guessing with low-carb “keto” days, some higher-carb days, and then fasting days as well.

Self-Care

All the benefits that feminism has brought women have also put more on their plates than ever before. Women now face pressure from every angle, with an often perpetuated belief that “we can do it all,” at home and out of the home. Although this is true, the mentality also leads to a general disregard for the reality of burnout.

Managing stress is vital if you want to implement fasting in your life. Like eating enough and getting quality sleep, having a self-care routine can help mitigate daily stressors. Self-care is a bio-individual process that requires knowing which tools you can implement to support your mind and body.

Self-care can look like many things, including:

• Asking for help
• Saying no
• Taking a mental health day from work
• Taking a nap
• Calling a friend to talk
• Canceling plans

Fasting Options for Women

The key with fasting will constantly be tuning into your own bio-individual needs. Avoid rigid dogma, and use the guidelines below as a suggestion. If you try a new fasting routine and your sleep quality tanks, your mood becomes destabilized, or you experience brain fog: scale it back. Work on the pillars (de-stress, sleep quality, eating enough, and self-care), and then try again, perhaps with a more gentle approach.

A few approaches that can be used for fasting include:

Intermittent fasting is a daily feeding window on a 24-hour clock. A wider feeding window is better suited for women dealing with hormonal issues or stress until you address those stress pillars. Then, as you develop metabolic flexibility, you can extend the fasting window while still being mindful of never being too rigid.

Weekly fasting: can work well for individuals on a Monday-Friday schedule. This fasting variation could include a 5-1-1 split, with five low-carb days, one fasting day, and one high-carb day.

Monthly fasting: can work well for women and involves staying low-carb for most of the month with a weekly 24-hour fast and then going high-carb for the five days before and during your period. This helps reduce cortisol during this time of the month and pairs well with taking time for more rest.

Summary

There is no one-size-fits-all approach to fasting. Fasting requires an even more tailored approach for women in their reproductive years because of the cyclical female hormones that change daily. Cultivating a baseline of stress-resilience is critical, and then implementing a flexible fasting routine that serves you. Building stress-resilience and metabolic flexibility include habits like diet variation, introducing shorter periods of intermittent fasting, cleaning up the diet, reducing toxin exposure, and cellular detox. Women need to be more mindful of their hormones, sleep quality, self-care, and eating enough in their feeding windows.

Medical Disclaimer: information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. It is intended to share knowledge and information. This article has been medically reviewed by Dr. Charles Penick, MD, for the accuracy of the information provided, but we encourage you to make your own healthcare decisions based upon your research and in partnership with a qualified healthcare professional.

References

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