---
title: 'I Had to Stop Fasting...Should You? 5 Signs You Need To Take a Fasting Break'
source: 'https://youtube.com/watch?v=tkv6KRDVdVg'
video_id: 'tkv6KRDVdVg'
date: 2026-08-02
duration_sec: 1852
---

# I Had to Stop Fasting...Should You? 5 Signs You Need To Take a Fasting Break

> Source: [I Had to Stop Fasting...Should You? 5 Signs You Need To Take a Fasting Break](https://youtube.com/watch?v=tkv6KRDVdVg)

## Summary

Dr. Mindy Pelz discusses whether fasting is right for everyone, emphasizing that fasting is a hormetic stressor that may not suit individuals already overwhelmed by stress. She presents five physiological signals—sleep, energy/mood, hormonal rhythm, muscle/strength, and weight—that indicate whether fasting is working or needs adjustment, along with five action steps to optimize fasting.

### Key Points

- **Fasting as a hormetic stressor** [01:16] — Fasting applies mild stress that triggers beneficial adaptations, similar to exercise. However, if the body is already stressed, adding fasting can be counterproductive.
- **Metabolic switch and ketones** [02:53] — Around 12 hours without food, the body switches from sugar burning to fat burning, producing ketones that preserve muscle and support brain health.
- **Pulsing fasting pathways** [04:05] — Metabolic pathways like glucose/insulin and autophagy/mTOR are meant to pulse, not stay constantly active. Chronic fasting can lead to weight gain and stress.
- **Nervous system switch** [06:07] — Fasting shifts the nervous system from parasympathetic (rest/digest) to sympathetic (fight/flight). If already in fight/flight, longer fasts may be inappropriate.
- **Sign 1: Sleep** [08:53] — Green light: falling asleep easily and waking rested even on longer fasts. Red flag: wired at bedtime, waking early, unable to sleep, especially after pushing fasts.
- **Sign 2: Energy and mood** [11:18] — Green light: steady energy, calm mood, quiet hunger between meals. Red flag: shakiness, anxiety, irritability, brain fog, racing heart, indicating adrenaline crisis.
- **Sign 3: Hormonal rhythm** [14:00] — Fasting should align with menstrual cycle. Green light: regular cycle, good libido, minimal PMS. Red flag: cycle changes, hair loss, low mood, especially in perimenopause.
- **Sign 4: Muscle and strength** [19:12] — Green light: weight loss and muscle preservation. Red flag: scale not dropping, muscle breakdown, cold hands/feet, suppressed immunity, indicating chronic stress.
- **Action step 1: Minerals** [25:01] — Add minerals (electrolytes) during fasting to support the nervous system and reduce symptoms like heart palpitations and hair loss.
- **Action step 2: Break fast properly** [25:57] — First meal matters: include fiber, protein, fat, and some carbs (GLP-1 way) to feed microbes, restore amino acids, avoid glucose spikes, and boost serotonin.
- **Action step 3: Match fast to hormones** [26:44] — Use the fasting cycle for cycling women; post-menopausal women can fast longer but should pulse. Refer to 'Fast Like a Girl' for protocols.
- **Action step 4: Track one objective signal** [27:41] — Track sleep, HRV, cycle, morning energy, or ability to go without food for two weeks to gauge progress and adjust fasting length.
- **Action step 5: Deliberate reset** [28:24] — If three signs are red, pull back on fasting, rebuild sugar-burner system with good protein, fiber, and fat, then restart fasting gradually.

### Conclusion

Fasting is a powerful tool, but it must be pulsed and matched to individual stress and hormonal state. Listen to your body's signals—if three are red, dial back and rebuild your foundation before fasting again.

## Transcript

overwhelmed with their [music] stress loads. Looking at it through that picture, fasting might not be the best tool for a completely stressed out human. It doesn't mean fasting doesn't work. It
means that once again we need to think about [music] if fasting is right for about [music] if fasting is right for you. So, in this video, I am going to walk you through [music] five signals that your body will give you to tell you
if fasting is working or if fasting [music] is not working. I call them [music] is not working. I call them green lights and red lights. And I'm going to show you five action [music] steps you can do to either modify your
fast, stopping your fast, or do more fasting depending on where your stress loads are at [music] and how your nervous system is handling it. This is a video we've needed to do for you [music] for a very long time, and I can't wait
to dive into this. So, here we go. Let's go.
fasting is a stressor. So there there's that's not a secret. Hopefully you understand that it is a hormetic stressor. Hormesis is a good stressor.
This is how fasting works is that it applies just a little bit of stress on the system that causes your body to grow bigger and do better things. Just like
exercise, when you go and exercise, if you are lifting weights, you break you are lifting weights, you break muscle down and that muscle is under stress, but it builds itself strong again. That's the same thing that's
happening with fasting. But it's if you think about it, it's when we're already think about it, it's when we're already in a broken down overwhelmed state. If we put more fasting on top of that, that's not a good system. The stress
that we put ourselves in, whether we fast, whether we exercise, whether we cold plunge or sauna, that is a signal, but it's in the aftermath of that, in
the recovery where the magic starts to hit. So, think of it like your metabolic switch. Remember how I taught you about the metabolic switch? You could when you eat, you're a sugar burner. There's no stress there unless
you're eating the wrong food like ultrarocessed foods. But then when you switch over into fat burner, this is called your metabolic stress. Ooh, now we're adding some stress to this. And I think of it like a light switch turning
on and turning off. And somewhere around 12 hours without food, you will come 12 hours without food, you will come over into this fat burning place and your body will start to go into this repair phase. Now, what's so incredible
about the human body is that it knows when it's over here that it needs to give you another fuel source. So, it gives you ketones. And I've done a ton on ketones. I'm such a fan on ketones, especially for brain health, especially
for post-menopausal women. So, I'm over here in a fat burning mode. I haven't here in a fat burning mode. I haven't eaten in 12 hours. My body, my brilliant body makes ketones, and it does that so it can supercharge the brain, but it
it can supercharge the brain, but it does it so that it can preserve muscle. So, those of you have heard, oh, fasting will break down muscle. Well, exercise and lifting weights breaks down muscle. And the beautiful part of the way the
internal mechanisms are in our body is that the more ketones you make, the more that the more ketones you make, the more muscle preservation that you will will muscle preservation that you will will create. Now this metabolic switch, it is
not meant to be turned on or turned off all the time. If the metabolic switch is turned off, meaning you do not go into a fat burning state, you have a tendency
to gain more weight if you're not eating the right foods. If this metabolic switch is turned on all the time because you love fasting and you've been fasting over and over and over again, you also can go into a
weight gaining place because the body is under so much stress. So why don't we fast forever? Why don't we do one meal a day over and over again? Is because these pathways, this glucose and insulin pathway, this autophagy and mTor
pathway, these all of the ways I've tried to explain it to you all over the tried to explain it to you all over the years, those pathways are meant to years, those pathways are meant to pulse. They are not meant to be on all
of the time. Just like we're not meant to have daylight all the time or nighttime all the time. There is a rhythm here that we're meant to to look at. So the question is never is fasting good or bad. it. The question is how
much time am I spending in the stress hormatic response and how much time am I spending in the recovery part and how am I mapping that to the stress of my life. This is where hopefully you've heard me talk about the end of one and how
important it is that we take videos like mine. We take or anybody's we take books like Fast Like a Girl and we customize it for us and make it right for us. Because the whole reason I wrote Fast Like a Girl, the whole reason was to
teach the pulsing of fasting. And I find it comical that people think I'm the fasting queen and that I just want everybody to fast all the time. I wrote a whole book on when to not fast. So let's let's come back to some sense of
let's let's come back to some sense of reality here. Now you have a metabolic switch but you also have a nervous system switch. One side of the equation for your nervous system is a parasympathetic nervous system. It is
your rest and digest nervous system and it gets activated when we eat except when we eat ultrarocessed foods because there are so many chemicals in there that stimulate us. But when you're eating whole foods that in a good meal
that you are in a hopefully in a parasympathetic state and then when we fast we go into fight or flight. we go into a little bit more of an adrenaline
situation. So, we have to map when we're looking at if fasting is right or wrong for you, we also have to map where your nervous system is at. So, if your nervous system is already locked over here in a fight
orflight situation and you decide to do a 24-hour fast or you decide to do a 36-hour fast or a three-day water fast, that might not be appropriate for you because you were already in a fight orflight state. I have a beautiful
questionnaire I just created that I'm using with my reset academy members and I want to pass it on to you and it's called a nervous system reset and there is a questionnaire in there. You take the questions, answer them, do the do
there's a a scoring uh uh program there and look and see where your nervous system is at because if you're completely maxed out, fasting isn't your completely maxed out, fasting isn't your tool. Now I want to dive in to these f
these steps of how do you know physiologically physiologically that you are meant to fast or you should maybe back away from fasting because I've seen this over and over and over
again where one woman can do an 18-hour fast and she freaking rocks it and another woman does an 18-hour fast and her hair falls out and she gains weight and she feels horrible. Let's the same fast, different body,
different nervous system. So, let's start to walk through these signs of how you can tell where you're at. I do want to say if you want the nervous system reset questionnaire I have, just put nervous system reset in your comments
because that is a great gauge that I created to help you also see if you should be more in your sugar burner mode or more in your fat burner mode. So, here is the first sign I want you to look at, and it's sleep. Woo! Okay. Yep.
We're going to go there. Are you ready? So, your green light is that you fall asleep easily, and you wake up rested, even on longer fast days. That's a sign
switch is working well, your nervous system switch is working well. I decide to go into a 24-hour fast. I'd maybe do a three-day water fast, and I'm pretty good. I sleep okay. I can tell you the first time I did a three-day water fast,
that moment. I was testing all these tools out and one of the symptoms that I had was a pounding heart, like a heart palpitations. Um, I now know that minerals can help that. But if minerals don't help that
be because your nervous system can't take the load of going that long without uh without eating. I also have heard from many of you that when you go into
these longer fasts, you can't sleep. And it doesn't happen to everybody, but it does often happen to the people that were already maxed with their sleep levels. And so, what they need to start to do is a little shorter fast. We'll
talk about that here in a moment. Now, a red flag with your sleep on your fasting days that would say come out of the fast is if you're wired at bedtime, you can't fall asleep. You're waking in the early hours and you can't get back to sleep.
And specifically, that day you really pushed your fast. Now, I'm going to leave a um another video that I've done on why you wake up at 3:00 a.m. And for some of you, it's because of cortisol. It's not and you were already in that
It's not and you were already in that cortisol rich state. But I really want you to understand that if you are fasting chronically and you're still waking up consistently at 3 in the morning that we may need to just dial
back on your spouse a little bit. So ask yourself in this first question, this yourself in this first question, this first sign is does your sleep get worse on longer fasting days? Longer to me is something over 24 hours. And if it's yet
the answer is yes, then we need to dial back to shorter fasts. back to shorter fasts. Okay. Sign number two is your energy and your moods and especially in between meals. A green light is that you have a
metabolic switch that is working really smoothly and you can go a significant period without food and your energy is steady. It is clear. It is calm. Your hunger is quiet. That would tell you if you're 16, 17 hours without food, that
would that would tell you that you're doing great, that you're that keep going. I've had some three-day water fasts where I just felt great for three days straight. Some of you might have that. That's a sign that my nervous
system was ready for that fast. If you start to fast and it you get to that 24 hours or you get over 24 hours and you're shaky and you're anxious and you're irritable and you're foggy and you're hangry and you have trembling
hands um and you have a racing heart and you're snapping at people, you have gone too far in the fast and you need to start dialing it back. So adrenaline
start dialing it back. So adrenaline will send a signal to tell your brain that it's doesn't have enough fuel. And so when adrenaline kicks in and you get the racing heart and the shaking hands and you're irritable and your OCD brain,
that is a signal. Remember, we're a chemistry lab. So when that is a signal telling you that no food is putting your body in a crisis state, not all of you
will get that with fasting, which is why this is not a video on on everybody stop fasting. This is a video on how do we be the end of one of our fasting
the end of one of our fasting experience. So, if you are crashing in between meals and your moods are horrible, um, and it's time to start to go back to the lower fast and build some base here. A 13-hour fast has great
research on preventing a reoccurrence of breast cancer. A 15-hour fast does amazing job for growth hormone and getting you more um anti-aging. the
growth hormone is an anti-aging tool and helping you burn fat. A 17-hour fast is amazing for getting rid of those zombie cells that speed up age aging and for
getting rid of cancer cells. There's so much magic that happens in those lower fasts. I wrote about all six of them, by the way, here in my book. Um, but you might need to go back. It might not be your body might not be ready for the
longer fast, and that's okay. That's not weakness. That's actually strength. That's showing you're showing your body, hey, I trust you. I got you. I'm I'm listening to you. That is so important to come back into a positive
relationship with your body. Okay. Sign number three. This was the heart of fast like a girl. This was the whole reason I wrote this and it's your cycle and your hormonal rhythm. So when I first started fasting and falling in love with the
science of fasting, using it as a tool with my patients, I noticed for my own self, I was in my mid-40s that my period was starting to stop and that when I did get my period, the symptoms were horrible and there was big I was like
having really big heavy hemorrhaging type periods. And at the time I thought type periods. And at the time I thought it was pmenopause, but I had had combined perry menopause with a lot of longer fasts. And so I was putting
myself too much in this sympathetic dominant state. And so I started playing with, wait a second, maybe there are times of the menstrual cycle that we should fast and there's times we shouldn't. And that's where I came up
with the fasting cycle. And this fasting cycle continues to be a resource that over a million and a half people have bought this book and have used it. And that you go look at my Amazon reviews. So many people's cycle has come back
because they discovered how to fast with a hormonal rhythm. I will give you three really simple ways to look at your hormonal rhythm. If you are a woman who
is cycling, you're, you know, in your 30s, 20s, maybe in your teens, then you want to fast according to the fasting cycle. If you are pmenopause
and your hair is falling out and you're spotting and you're irritable, you're going to want to stay to shorter fasts, especially if you can really do it most most of the cycle, but not the week before your period. And you're going to
want to stick to lower fasts. If you are a post-menopausal woman woman, you can fast longer. Those ketones are really going to help you. So, especially with brain. So, I it same woman just aging along in different hormonal rhythms. And
for my post-menopausal women, I have a whole chapter on fasting and ketones in Age Like a Grill. Now, a green light with your hormonal rhythm would look like, I'm fasting. I'm doing the fasting cycle. I still have a I still have a
cycle. The cycle is regular. It's predictable. My libido is fairly good. And I don't have a lot of PMS. That would tell you whatever you're however you're fasting right now, it's working. A red flag would be that you're still
cycling, but all of a sudden your cycle stretches out or it lightens or or you start skipping it or your PMS is louder. Your sex drive is gone. Now, with post-menopausal women, a green light is you have a stable mood, your
flashes, you're not losing hair when you're fast. Whereas a red flag for post-menopausal women would be, "Oh my gosh, I've got more hot flashes. I have
a racing heart. My hair is shedding, clumps are coming out, and a low mood is starting to creep in." So, the brain senses when no energy is coming in, and it protects you when it has gone a long
period of time without fuel by shutting down reproduction. So your cycle, your down reproduction. So your cycle, your libido, your hair, they are signs of Are you getting the right amount of fuel? And if you start to look at those
as just indicator lights, just like we look at on our car, um we can start to look at on our car, um we can start to see if this fasting length is right or not right for us. So, when it comes to hormones, cycling your fast, whether
you're post-menopausal or you're in your most fertile years in your 20s and 30s, we there are times to fast and there are times to not fast. And understanding what's right for you is an art, which is why I wrote a whole book on it. I even
have a membership group called the Reset Academy where women are in there learning how to make their own end of one experience there. You can join us over there. just put reset academy and we'll send you info on it. But more
importantly, I just want to make sure you understand you're rhythmic. You have a rhythm that and so we need to ri have rhythm with our exercise. We need to the things that has really crushed my heart is that there is a rhetoric out
there that menopausal women shouldn't fast. and they say that because their hair falls out and all of a sudden as they're moving into their menopausal years, they're having really bad symptoms, but that's not the case. The
case is that we need to learn how to pulse fasting in and out, in and out, and match it to our hormones. Number four, I won't keep going on that one. Uh, your muscle, your strength, and your shape will tell you if you are fasting
too much. And here's what it looks like. So the green light with fasting, I want you all to hear this because I've done thousands of videos here on YouTube on thousands of videos here on YouTube on belly fat on uh weight gain. It is a
very popular talk topic here on my channel. When you are fasting correctly, you should lose weight. So a green light is that you can drop weight when you
fast. Just like the millions of people that bought this book and lost hundreds and hundreds of pounds, we just did in our reset academy, we did a two-week our reset academy, we did a two-week experience where we took 600 women
through different fasts, cycling in different fast foods, and the average weight loss was 5.8 pounds in two weeks. That is healthy weight loss. You can join us if you ever want to join us. just put burn fat like a girl in the
comments and my team will send you links for the next one. But more again, more importantly, it was because I walked these women through a rhythmic experience. Their food noise went down. They lost weight. That's a green light
because they were taught how to have how to use fasting to pulse in and out. A red light is that the scale actually doesn't drop when you fast. You may actually be going in the opposite direction and you may be breaking muscle
down. Ketones are supposed to preserve muscle. But it when we move from a hormetic stressor into a chronic stress state, all of a
sudden muscle will break down. Your adrenal glands and your muscles use many of the same amino acids to function normally. So when you are asking your
normally. So when you are asking your adrenal glands to constantly be on call, whether it's stress from your life, stress from a longer fast, and it doesn't have the right nutrients to do that, what it will do is break muscle
down. It will grab nutrients like amino acids from muscle to be able to support acids from muscle to be able to support the adrenal glands. Now women over 40, a lot of what you're doing as you go into pmenopause and into post-menopause is
your ovaries are asking your adrenal glands to work extra hard. So if you're a red flag would be I can't lose weight and I'm losing muscle. That is not a
good scenario and you're going to want to dial your fasting back a little bit. to dial your fasting back a little bit. Um and again easy signal to look at. So another piece of this I want to point out is the thyroid gland. And the
interesting part about the thyroid gland, another another topic that has fasting getting lots of criticism. I have done multiple videos on here on the
have done multiple videos on here on the thyroid. And yes, T3 goes down. the bioactive version of T3 goes down when you fast because the body goes into an energy conservation state, but it doesn't. When you bring food back in,
especially that first meal, when you refeed in a really good way, what happens is you restimulate the thyroid and all the thyroid hormones start to come back into balance. It's like a
come back into balance. It's like a reset. But if I'm a stressed out woman who's like, I used to get great results with fasting. I'm just going to do more of it. I need to do more of it. And you're not getting that great result.
And your hair is falling out and your heart is racing and you're not the scale isn't budging. Then you are bringing those thyroid hormones. You're cold. Your cold hands and feet. bringing those thyroid hormones down to to a level that
thyroid hormones down to to a level that is not working for you. So again, this is not working for you. So again, this is why we pulse fasting. So cortisol, by the way, that never comes down. Cortisol, when you're living in this too
much fasting state, can also suppress the immunity. So if you're fasting and you're getting sick all the time, that's not great either. I've actually seen um I've seen more people have an improved immune system from fasting. Not the
opposite, but if you're getting sick a lot, you may be in this this metabolic breakdown moment. Now, before I go into the six things or the five things I want you to do, I really can't emphasize enough. I do not want any of you walking
away from this video thinking fasting's the enemy or saying, "Ah, Dr. Mindy changed her mind on fasting." There are little tweaks I have changed my mind on. Not on all of fasting. I still think fasting is one of the greatest healing
tools that we have and it is free. But we have to start to learn the art of cycling fasting, which is where I started with Fast Like a Girl back in
December of 2022 when this book came out. It was the only fasting book that was teaching this cycling approach to female hormones. It is the dose of
fasting that's the medicine, not the poison. And the right dose is unique to poison. And the right dose is unique to you. Your dose of fasting and my dose of fasting may be completely different. Your dose of fasting and your husband's
dose of fasting totally different. So don't fall prey to people saying women shouldn't fast or po or menopausal women shouldn't fast. They don't understand shouldn't fast. They don't understand the power of pulsing fasting. Okay, here
are the five action steps I really want you to start to do. And these action steps are from easiest to hardest. First, I'm a huge fan of putting minerals having minerals when you fast. Let's just let's not put an extra load
on on your nervous system. When you lose minerals, now the nervous system is even stressed about that. So, let's get some element tea. I'll put again links. You can do these electrolyte packets. You can do the cans. There's all kinds of
brands. I also like bean minerals. Again, all the all the the products I love with discount codes will be in the notes. But, let's put minerals in first and see if the hair stops falling out. Let's see if the if the heart stops
racing and then you'll know was it my nervous system or was it minerals. So that was number one. Okay, this is my favorite thing I want you to know so
bad. I keep doing videos on it. Please tell me if you're getting it, which is tell me if you're getting it, which is breaking your fast matters. That first meal matters. It is the most important meal that you have. So breaking it fast
meal that you have. So breaking it fast matters. I like doing it the GLP1 way, which is let's make sure we have fiber, protein, fat, and then some carbs. But you need that fiber to feed the microbes so they make GLP-1 hormone. You need the
the protein so you can re get the amino acids back in the muscles. You need fat so you don't end up with a big glucose spike. And then you can put your your carbs in there to get yourself some serotonin. So
break your fast like it matters, like your your life matters. Okay. Number three is that you're going to match your fast to your hormones, your hormonal state. So I have a whole book on it. You can It's called Fast Like a Girl if
you're new to me. Um, I wrote all about how do you fast your hormones. For my how do you fast your hormones. For my post-menopausal friends, you can fast however you want. I like you more doing like a weekly schedule like a 511 um or
like a weekly schedule like a 511 um or a 421. I put protocols in here. Um, I really think that post-menopausal women do incredibly well with fasting. it's do incredibly well with fasting. it's easier and they get those those ketones
so that they can start to fuel their brain in a new way and they get the brain in a new way and they get the muscle preservation. So, um and again, if you need more information, dive into the book so you can find yourself or
come join me in my academy. Okay. Number four, I want you to track one objective four, I want you to track one objective signal for two weeks. Track your sleep. Track your HRV. Track your cycle. Track your morning energy. Track your ability
to go without food. Whatever it is, track it. I've got a bunch of trackers. I can't reach it. In my fast like a girl journal. Uh you can write it all down. That was what the Fast Like a Girl journal was meant to do. Um so you can
we'll put leave links for that. But track something so you can see your progress and you can see if you need less or more. Number five, less or more. Number five, if three of the signs I talked about are
red, run what I call a deliberate reset. Pull back on fasting and start to rebuild your sugar burner [clears throat] system. I want you to rebuild it with good protein. I want you to rebuild it
with uh with fiber. I want you to rebuild it with good fat. But more importantly, dial it back. If you had three, you listen to those signs and really hard for me to fast. My hair is falling out. I'm gaining weight." Dial
falling out. I'm gaining weight." Dial it back and start over by really getting that sugar burner system in place. I have a book that I wrote called Eat Like a Girl where I have so many recipes in here and lists of food. Come back to
good eating and then go to fasting. Go back to fasting. It is amazing how it works. Or again, come join us in burn fat like a girl experience. Just put burn fat like a girl in the comments and my team will send you a link. So what I
want you to say when you're not getting a good fasting [music] result is I want a good fasting [music] result is I want you to ask yourself, is my body adapting you to ask yourself, is my body adapting or is my body struggling? [music]
because we want your body to be adapting to this metabolic switch, [music] not struggling with it. Now, I know a lot of you have friends that have been fasting, [music] and if you have some or a spouse that's been fasting, send them this
video because this again might be one of the most important videos I ever put And I want to make sure everybody is fasting in accordance with their is safe. [music] And I want to make sure that you're getting the best of fasting,
that it's not tanking you into [music] a chronically stressed state. If you've mixed your fasting up and you've done the rhythm, put them, tell us [music] your story so we can all learn from it. But most importantly, don't give up on
[music] It's just a few tweaks that is going to have you getting the results again and making fasting feel effortless. As always, I hope that helped. I have videos on how you can start to create a
videos on how you can start to create a foundation with your food that gives you balances your nervous system but also will give you more GLP-1 hormone. You make GLP-1 hormone. That video is right here. You can go and check that video