You’ve heard those dirty little rumors about women trying intermittent fasting – it’s dangerous for their health, right? Not exactly.
So, why the rumors?
As with many relationships, it’s complicated. But I’m here to break it down and make all the science make sense.
Once you have a better understanding of your body (namely, your hormones), you’ll be able to confidently enter an intermittent fast without any worries.
Let’s put those rumors to rest and look at the science behind intermittent fasting for women.
How Intermittent Fasting Affects Your Hormones
So, how and why does intermittent fasting affect women differently than men? It’s all comes down to hormones.
Hormones are the messengers that keep your body functions working. There is a domino effect when it comes to hormones – if one is thrown off balance, the others may also be negatively impacted.
From energy to digestion to metabolism, you don’t want to throw a kink in things!
And intermittent fasting can do just that – it may upset the delicate hormone balance going on in your body. Let’s look at the different types of hormones that are affected by fasting.
Why are women more sensitive to these hunger hormones? It’s the body’s protection mechanism. A woman’s body is designed to carry and protect a baby, so the body wants to make sure it’s well-nourished to protect a potential fetus (even if you’re not pregnant).
So that insatiable hungry feeling you get is legit – it comes from your body producing extra hunger hormones to get you to eat.
The female hormones estrogen and progesterone directly affect ovulation and fertility (among other things).
But there’s a chain of events that leads a woman’s body to produce these hormones – mess with one link and there’s a ripple effect through the entire chain.
It all starts with a hormone known as GnRH. This hormone zooms around and signals the release of other hormones, eventually triggering the production of estrogen and progesterone in women (or the release of testosterone in men).
GnRH is a sensitive little booger, and it can easily be thrown off by fasting. But both men and women have this same chain going on.
So, if fasting affects GnRH, then shouldn’t it affect both men and women equally?
Ah, there’s more to the story.
Enter, kisspeptin – the hormone that gets things done. Kisspeptin regulates GnRH production in both male and females.
And you know what makes kisspeptin go haywire? The hunger hormones (yup, leptin and ghrelin are back in the picture).
While both sexes produce kisspeptin, women produce more. So, more kisspeptin in the body means more sensitivity to the hunger hormones.
In the dieting world, thyroid has practically become a dirty word. However, it doesn’t appear that fasting directly affects your thyroid.
While it’s true that your thyroid activity is lower during your fasting window, your thyroid activity takes a similar dip between regularly spaced meals.
However, it’s always a good idea to get your thyroid levels checked regularly – the thyroid hormones affect every single cell in your body. So, if the thyroid isn’t happy, nothing is happy.
Possible Negative Side Effects for Women Who Intermittent Fast
What happens if your hormones go haywire while fasting?
Of course, as discussed in a previous article, there are a myriad of benefits associated with IF.
But there are also a lot of negative side effects that women may experience if they don’t use caution when intermittent fasting. Here are just a few.
- Irregular periods, or even a complete loss of your period.
- Metabolic stress.
- Anxiety and depression.
- Difficulty sleeping.
- Fertility issues.
With intermittent fasting, the trick is to not let your hormone signals for hunger get out of control.
As a woman, you must know your body and keep an eye on how you react to different lengths of fasting.
Best Intermittent Fasting Methods for Women
Because women are super sensitive to hunger hormones, there are certain types of intermittent fasting that work best for the female body.
Most of these methods focus on easing your body into intermittent fasting, rather than taking an overly aggressive approach.
You can learn more about these intermittent fasting methods here.
This method eases you into intermittent fasting, giving your body and hormones a chance to adapt, rather than shocking them into the fasted state.
The Crescendo Method is an ideal place for women to start when first getting into intermittent fasting.
Following this method, you fast only a few days per week and make sure those days are spread out through the week.
Your fasting window lasts from 12-16 hours, and your eating window is 8-12 hours.
After a couple of weeks, feel free to add in another day of fasting each week and lengthen your fasting window to the full 16 hours (if you haven’t already).
This is similar to the Crescendo Method but with the longer fasting window (16 hours). Additionally, this method is done every day rather than on non-consecutive days.
This is an entire 24-hour fast, which can be difficult for many.
However, if you stop eating at dinner one day and then resume eating at dinner the next day, you still get a meal on each of the fasting days.
Only use this method 1-2 times per week and ease into it.
This is another relatively relaxed intermittent fasting method that keeps your hormones from doing a nosedive.
With this method, you eat normally on 5 days of the week but restrict calories (typically to 500 per day) for the remaining 2 days of the week.
Bonus Hacks for Women Who Intermittent Fast
- Don’t fast for longer than 24 hours at a time – ideally, you should aim for 12-16 hours.
- Don’t fast on consecutive days when you first start fasting (for at least the first 2-3 weeks).
- Hydrate! Drink lots of fluids during your fast. At first, you may even want to try fluids with a few calories, like bone broth or herbal teas.
- Keep exercise light on fasting days. Yoga is a great low-intensity exercise for fasted days.
If you’re a woman, don’t let those silly rumors keep you from trying intermittent fasting.
I’ve broken down the science and armed you with the knowledge to put those rumors to rest.
If done correctly, intermittent fasting is perfectly safe for both men and women alike!
Lilli a regular Contributor & Editor who is a weight training enthusiast with a background in both CrossFit and powerlifting. She lives on a ranch in Texas where she has built an amazing home gym right in her own backyard (err, garage). When she’s not working out, Lilli works as a freelance writer and travels as often as possible.