Fasting for non-religious causes – and whether or not it’s good or dangerous for you – has develop into a scorching subject within the well being and health house. Everybody has an opinion and so they appear to be getting increasingly more obsessed with it by the day.
Leap into the feedback part of an Instagram submit of fasting and also you’ll see what I imply.
Personally, I get up HUNGRY.
My sister can’t have a look at meals earlier than midday.
I really feel like crap if I don’t eat earlier than understanding.
My buddy Jules seems like crap if she does eat earlier than understanding.
Way back to 2019, “intermittent fasting” was one of the vital searched diet-related phrases on Google and the subject solely appears to have heated up since then.
With all of the hype round fasting, particularly for girls, it’s simple to get caught up within the pattern. However right here’s the factor: fasting for girls isn’t so simple as it could appear.
After diving into the analysis, my greatest takeaway is that this: Irrespective of your opinion on fasting, you’ll possible discover analysis to assist your standpoint. However relating to fasting for girls, we have to think about some essential components, from the analysis gaps to how fasting impacts lively girls’s wants for power, muscle restoration, and hormonal stability. Right here’s what you must know.
What Is Fasting, Actually?
Fasting merely means taking a break from consuming (and typically consuming) for a set time period.
Technically, all of us quick in a single day whereas we sleep—and that fasting window is definitely essential! It offers our our bodies time to relaxation, restore, and faucet into saved power as an alternative of continually processing new meals. And breakfast is actually the meal once we break the in a single day quick.
This pure “pause” requires that our our bodies expend glucose and fatty acids circulating in our blood and faucet into power shops. It trains our our bodies to get higher at processing power.
However What About Longer Fasts?
Some folks deliberately stretch that in a single day quick into an extended break, a apply generally known as intermittent fasting (IF). Probably the most in style variations is named time-restricted consuming (TRE), the place you restrict your consuming to a particular window – typically round 8 hours (or much less) – and quick the opposite 16 hours of the day.
For instance, you may eat dinner at 6 p.m. after which not have any extra energy till 10 a.m. the subsequent day—so that you just’re fasting in periods of low or diminished exercise.
There’s a Lack of Analysis on Fasting for Girls
A lot of the analysis on fasting has been carried out on males and lots of have solely been carried out on animals. Individuals who assist fasting typically make the leap that findings of these research apply to girls as effectively, however that’s a fairly large leap as a result of girls’s our bodies reply in a different way than males’s (or mice)—particularly relating to diminished calorie consumption, our hormonal cycles, and train.
The huge majority of research on fasting for girls deal with sedentary girls and people think abouted chubby or overweight. However with small pattern sizes it’s onerous to generalize the findings to lively girls and those that should not thought of chubby or overweight.
We do see that for individuals who are inactive or sedentary, research have proven fasting generally is a useful stressor on the system that helps enhance insulin sensitivity, glucose metabolism, amongst different issues.
However in case you are an exerciser or an lively girls or in perimenopause, there’s a main hole within the analysis that makes it even more durable to use the present fasting analysis to your life—particularly relating to understanding how fasting impacts train efficiency and restoration.
Fasting for Weight Loss
The analysis on fasting and weight reduction is kind of clear: on the finish of the day, relating to weight reduction, fasting is basically only a methodology of calorie restriction. Whereas proponents declare fasting has particular metabolic advantages, there’s no strong proof displaying that it’s any more practical than different types of calorie management, like portion management, monitoring your meals consumption, or balanced consuming.
Fasting is only a methodology of lowering your calorie consumption by utilizing the clock to restrict your consumption. And when calorie consumption is managed for, fasting isn’t higher than different “diets” for reaching long-term weight reduction or well being enhancements.
Fasting and Train
Combining fasting and train is the place it will get difficult—particularly for girls. Primarily, it is because fasting and train do related issues—they each lower your blood glucose and different essential molecules circulating in your blood.
So once you mix them and train whereas fasted, you may find yourself with some points.
First, for each women and men, exercising fasted might make your blood sugar ranges go too low and depart you attempting to actually run on an empty tank. No fuel makes it actually onerous to work out or work out onerous sufficient to get the outcomes you’re after. It might additionally make you dizzy and go out.
Second, fasted train is related to decreased efficiency, elevated fatigue, diminished ability, impaired focus, and an elevated notion of effort (so train feels more durable than it ought to). This makes it much less possible that you just’ll have good coaching periods and even need to work out.
Moreover, muscle preservation is crucial for total well being and metabolism, and fasting alone might not do the job in addition to different consuming methods that prioritize protein and carbohydrates for muscle restoration and development.
For girls who do select to quick or exercise fasted, it’s essential that they proceed to deal with consuming sufficient meals – particularly protein and carbs – all through the day throughout their feeding window to attenuate the chance of low power availability and stop muscle breakdown and loss.
Self-Consciousness: The Key to Making Good Fueling Selections
Whether or not you’re fasting or following one other consuming plan, self-awareness is essential. Everybody’s physique is totally different, and which means tuning into your private wants and the way your weight-reduction plan (and train) impacts your power, temper, and efficiency.
And context issues—so keep in mind that it’s not nearly skipping that one meal, it’s about the way you’re balancing your wants throughout the day as effectively. So what works for one particular person, might not be just right for you. And what used to be just right for you, might in the future not be applicable or efficient.
Some girls thrive on fasting, however many others discover that under-eating or fasting interferes with their exercises and restoration.
Everybody’s physique has distinctive wants, and there’s no one-size-fits-all strategy.
Once I introduced up the subject of fasting to my colleague, Jules Mitchell, creator of Yoga Biomechanics: Stretching Redefined, she shared how difficult it may be for individuals who weren’t athletes rising as much as acknowledge their physique’s alerts.
“The older I get, the extra privileged I really feel for having performed sports activities as a child and spent my childhood operating races. At eight years outdated, I discovered {that a} half banana earlier than a 10k would make me sick. I’ve been being attentive to my physique’s alerts my entire life. However for those who’re simply now in perimenopause and stepping into train, all of the blended messaging have to be so complicated.”
Her expertise reminds us that self-awareness isn’t nearly noticing what we really feel at the moment—it’s about understanding how our our bodies reply over time, by way of totally different phases of life and exercise.
In case you’re always feeling drained, weak, or sluggish throughout your exercises, it is perhaps an indication that you just’re not fueling your physique correctly.
Self-awareness is about listening to your physique and making changes primarily based on how you’re feeling, not simply following the most recent pattern.
Many Energetic Girls Are Typically Beneath-fueled
One of many key factors that always will get neglected relating to fasting for girls is the difficulty of under-fueling.
Many lively girls underestimate their whole every day power expenditure (because of all these foolish 1200-1500 calorie weight-reduction plan suggestions that we grew up with) and find yourself consuming too little to fulfill their power calls for. That is very true for girls who do common energy coaching, high-intensity exercises, or endurance coaching.
A 2016 research carried out on 109 feminine leisure exercisers discovered that 45% have been in danger for low power availability – that’s almost half of the ladies recruited from native gyms and health facilities have been in danger as a consequence of under-fueling.
So under-fueling and low power availability aren’t only a concern for “high-level” athletes, any exercising lady will be in danger.
Beneath-fueling can result in poor restoration, decreased efficiency, and even hormonal imbalances. Girls who prepare onerous want to make sure they’re consuming sufficient carbohydrates and protein to gasoline their exercises and get better successfully. With out the right vitamins, your physique can’t rebuild muscle, and you could expertise fatigue, temper swings, and hormonal disruptions.
In my work as a private coach serving to girls with osteoporosis construct and preserve bone mass, most of my discussions with purchasers encompass consuming extra, not much less.
Dietary Therapist Michaela Smith agrees. She shared her ideas with me:
“The overwhelming majority of girls I work with are under-fueling already, even those that want to shed pounds! Beneath-eating is a major stressor that may manifest into hormonal imbalance, weight modifications, and even cognitive modifications.”
In her apply, she usually doesn’t suggest intermittent fasting for girls. Right here’s why:
- Many ladies are already under-eating, which may contribute to nervousness, mind fog, overwhelm, and hormonal imbalances.
- Fasting can negatively have an effect on blood sugar, resulting in:
- Drops in blood glucose
- Launch of stress hormones
- A rebound spike in blood sugar
- A “blood sugar curler coaster” that leaves girls feeling off stability when it comes to power and meals cravings
- There’s restricted analysis on the results of fasting on girls, making lengthy fasts a questionable technique.
As a substitute, Michaela recommends the next strategy to assist regular power and hormonal well being:
- Eat a balanced breakfast inside 30–60 minutes of waking.
- Gas constantly all through the day with common meals and snacks.
- End dinner early sufficient to permit time to digest and profit from a delicate in a single day quick.
- Purpose for a 12-hour window between dinner and breakfast—this helps power metabolism and intestine well being with out over stressing the physique.
“The long-term outcomes I see with the ladies I work with are extra even power, fewer jittery emotions, improved blood sugar response, and extra steady weight. All wins in my e book!”
When You Eat Issues, However So Does What You Eat
Whereas timing your meals or solely consuming inside a particular window might sound stylish, it’s extra essential to deal with what you eat and whether or not it meets your physique’s wants. Whether or not you’re consuming earlier than or after your exercise, be sure to’re getting sufficient carbohydrates to gasoline your train and protein to get better.
Carbohydrates are your physique’s most important supply of gasoline for train, and it’s essential to replenish glycogen shops after exercises. The amino acids in protein are the constructing blocks for all tissue and helps rebuild muscle, preserve bone, and assist restoration.
For lively girls, this stability is vital—irrespective of once you eat. It’s all about giving your physique the vitamins it must get better and carry out at its finest.
In case you’re not used to consuming earlier than you’re employed out, however you need to attempt it, begin small with simply 100 energy of easily-digestible, low-fiber carbs or a sports activities drink to keep away from GI misery. Then, over time step by step enhance the energy to coach your system to tolerate meals at the moment of day.
Fasting and Hormonal Well being: A Advanced Relationship
For girls with polycystic ovary syndrome (PCOS), intermittent fasting has proven some promising advantages in bettering insulin sensitivity, regulating blood sugar ranges, and selling hormonal stability. A number of research have recommended that fasting can cut back insulin spikes, a key situation in PCOS, and should assist alleviate signs like irregular menstrual cycles, weight acquire, and pimples.
Nevertheless, it’s essential to notice that the majority of the analysis on fasting for PCOS has been carried out on chubby or overweight premenopausal girls and the findings are nonetheless rising. Whereas the outcomes are encouraging, extra analysis is required to grasp how intermittent fasting impacts girls with totally different physique varieties and at numerous phases of life, together with those that are lively and in perimenopause or past.
For lively girls, particularly these in perimenopause, fasting can affect hormonal stability in ways in which might not be instantly obvious. Low power consumption, particularly when mixed with plenty of train, can result in low power availability and/or in the end Relative Power Deficiency in Sport (RED-S), a situation that impacts reproductive, metabolic, and bone well being. Indicators of RED-S can embrace menstrual irregularities, fatigue, decreased bone density, and poor restoration.
And right here’s the kicker: throughout perimenopause, distinguishing between anticipated hormonal modifications and the indicators of RED-S will be tough.
In case you’re experiencing fatigue, poor restoration, or irregular durations (which many ladies gained’t even have the ability to inform in the event that they’re utilizing contraception that alters their interval), it may very well be an indication that you just’re not fueling sufficient to assist your exercises and total well being.
Ample fueling, particularly with carbohydrates, is very essential in midlife to assist each coaching and hormonal well being.
Conclusion: Fasting for Girls—A Customized Method
Fasting may match for some girls, nevertheless it’s essential to keep in mind that, relating to weight reduction, it’s only one methodology of calorie restriction and it hasn’t been confirmed to be more practical than different dietary methods.
For lively girls, self-awareness and being attentive to how you’re feeling throughout exercises and restoration are essential. Earlier than contemplating a fasting routine, be certain your physique is well-fueled.
A balanced consumption of carbohydrates and protein is crucial—particularly to assist your exercises, restoration, and total well-being. Beneath-eating could make fasting counterproductive—growing stress on the physique fairly than supporting well being.
And for those who’re very lively or an athlete with targets—working towards a PR in your lifts or coaching for a contest or race—you could need to depart fasting within the mud as it will probably lower your efficiency and inhibit your restoration.
There’s no one-size-fits-all strategy. One of the best technique is well-thought-out and helps your power, efficiency, and long-term well being—not one which leaves you depleted.
And remember that there’s a rising variety of “medical doctors” and consultants on the market who’re talking about fasting (and benefiting from it) although it is vitally a lot out of their very own scope of apply. So earlier than diving in head first, be certain you examine what sort of physician they’re and confirm that you just solely take recommendation from certified diet consultants.
In case you’re uncertain the place to start out, think about getting assist from a registered dietitian or nutritionist who specialise in working with girls in your particular inhabitants (lively, endurance athletes, and/or perimenopausal girls) to assist tailor a plan that works for you. —Karin
References
- Vitality Professional. (2019). “Intermittent Fasting: A Search Pattern.” Vitality Professional Diet Statistics. Hyperlink
- Cienfuegos, S., et al. (2022). “Intermittent Fasting and Reproductive Well being: The Potential Results.” Vitamins.
- Correia, M., et al. (2020). “Intermittent Fasting and Cardio Efficiency.” Journal of Sports activities Sciences.
- Batitucci, G., et al. (2022). “The Influence of Fasting on Muscle Mass and Physique Composition.” Frontiers in Diet.
- Zouhal, H., et al. (2020). “Results of Fasting on Train Efficiency: A Assessment.” Sports activities Drugs.
- Mellin, A. (2025). “Carbohydrate Availability and Menstrual Well being in Energetic Girls.” Journal of Sport Diet and Train Metabolism.
- Aird, L., et al. (2018). “Fasted vs Fed Train: The Influence on Fats Metabolism and Efficiency.” Worldwide Journal of Sports activities Physiology and Efficiency.
- Slater, J., et al. (2016). “Feminine Leisure Exercisers at Danger for Low Power Availability.” Worldwide Journal of Sport Diet and Train Metabolism.