Episode 93: The Ins And Outs Of Intermittent Fasting

I'm Laura

I help nutrition entrepreneurs grow their income and their impact by packaging their brilliance into transformative coaching and consulting programs, and get crystal clear on their marketing strategy.

hey there!

TOp categories

Learn more

This post may contain affiliate links.

Thanks for joining us for episode 93 of The Ancestral RDs podcast. If you want to keep up with our podcasts, subscribe in iTunes and never miss an episode! Remember, please send us your question if you’d like us to answer it on the show.

Today we are answering the following question from a listener:

“What do you think about intermittent fasting or other fasts? I’ve heard they can be contraindicated for women especially. If one wants to try fasting, what signs should they look for to know if it’s having a negative effect? Is there a way to fast that would provide benefits but minimize risks? It seems there are potentially real benefits to fasting.”

Intermittent fasting has become a popular topic. We hear about the great benefits to health, but we also hear about the drawbacks and cautions against it. And with so many different fasting plans, it’s as confusing as it is intriguing. If you’re curious about intermittent fasting but don’t know where to begin to make sense of it all, you’ll want to listen today!

Tune in today as we talk everything fasting. Just some of what we’ll be discussing is the different methods of fasting, the benefits and drawbacks, and how to know if fasting appropriate for you. We’ll even be sharing tips on how to experiment with intermittent fasting to find a way that works for you.

Here’s what Laura and Kelsey will be discussing in this episode:

  • Evolutionary theory behind the Paleo community’s promotion of intermittent fasting
  • Explanation of different fasting methods
  • Autophagy as a benefit associated with fasting
  • Benefits of intermittent fasting on fat loss and metabolic function
  • The importance of tracking your calories during feeding periods when intermittent fasting
  • How the benefits of intermittent fasting can be obtained from caloric restriction
  • How those who are overweight can have more benefits and less negative effects associated with intermittent fasting than normal weight people
  • How women experience more negative effects from fasting than men
  • Why choosing the right time to fast is key
  • Why those with a history of eating disorder or a bad relationship with food should rethink intermittent fasting
  • Common symptoms associated with negative effects of fasting
  • Examples of illness that would benefit from fasting and illnesses that fasting would be detrimental


Links Discussed:


Kelsey: Hi everyone. Welcome to episode 93 of The Ancestral RDs. I’m Kelsey Kinney and with me as always is Laura Schoenfeld.

Laura: Hey, everybody.

Kelsey: How are you doing today, Laura?

Laura: Much better now that I’ve had steak for breakfast and dinner the night before.

Kelsey: Sounds great. I’m sure that helps.

Laura: Yes. It’s interesting, this episode is going to publish weeks after this happens. If anyone had been following me on Instagram or if they read my blog at all, they’ll have seen that I was doing a vegan fast as part of a spiritual fast with my church. I say vegan because it’s something called the “Daniel Fast” which is basically designed based on some different sections of the Book of Daniel, which is why it makes sense calling it the “Daniel Fast.”

Basically there’s two different sections where the prophet Daniel abstains from food, either pleasurable food animal food. They kind of combined that into a single fast. The animal food thing was about the availability of kosher animals products which they didn’t have available to them. Being Jews they said they’d rather not eat any animal products rather than eat something that’s not kosher. Then the second one was really just more fasting from pleasurable and enjoyable food and just subsisting on plain and simple food for three weeks.

Kelsey: Mm hmm.

Laura: The purpose of the fast for our church was to basically just realign our daily focus to prioritize a relationship with God. Instead of seeking food for physical comfort and pleasure, we were supposed to be doing things like praying, or reading the Bible, or listening to worship music, or whatever it was that we felt was promoting that relationship.

I thought it was interesting because a lot of my friends at church eat kind of like a normal diet. As far as I can see, they don’t eat crazy unhealthy or anything like that. But a lot of them do eat things like bread, and sugar, and dairy, and wheat, and all that. Those were the things that they were giving up. For me it was really I would say the meat thing was where I was making the biggest change.

Kelsey: Mm hmm.

Laura: So taking out eggs, taking out meat, and fish, and poultry, and not doing any animal fats. I wasn’t really sure what was going to happen because I do eat things like gluten free grains and legumes as side dishes. I was thinking well maybe I can handle it and I’ll just get some protein powder that’s plant based to make sure I get enough protein to feel okay.

Kelsey: Right.

Laura: I don’t really know why my body was like so not having it, but it really physically did not go super well. I only did it for 10 to 12 days, and even the last couple of days of that was modified with fish included.

Kelsey: Mm hmm.

Laura: But I was pretty shocked how terrible I felt and the weird changes that happened that I haven’t really experienced in a really long time. I think a lot of it had to do with the low protein intake, just dropping the total protein of each meal down to like 15 grams a meal or something. It was a huge change for me.

I don’t eat tons of meat, but eating a couple of ounces of meat at a meal is going to give you 20-30 grams of protein. Cutting that in half really made a big difference in how I felt after the meal and also between meals. I was hungry all the time even when I was kind of stuffed on the meal and I was even bloated from eating so many legumes, and fibrous vegetables, that kind of thing.

Kelsey: Right.

Laura: Then an hour later I’d be like, I’m starving again, this is terrible. It was kind of non-stop hunger. And then along with that, there was a lot of weird physical symptoms that happened which I think for me was like the stress hormone related symptoms. I was cold a lot and sometimes if I didn’t eat soon enough I would be so cold I’d actually be shaking and my teeth would be chattering.

Kelsey: Mm hmm.

Laura: I remember I was on the phone with my sister one morning and I hadn’t eaten yet and the phone call was going longer than I expected. And I literally was like shaking and I was like I hope she doesn’t think I’m freaking out about something because literally I just physically can’t control my shaking.

Kelsey: Yeah, wow.

Laura: Then here was a couple of days that I slept really bad. I think the first couple days I actually felt really tired and I slept a lot. I didn’t feel great after sleeping and I still had to nap and that kind of thing. But towards the end I was really having a hard time falling asleep and there was a couple of nights that I couldn’t actually even fall asleep until 2 or 3 in the morning, which was so annoying because I was so tired and I just felt so amped up.

Kelsey: Right.

Laura: And I would try to eat, but it wasn’t really helping. I remember one night I cheated and had a couple of eggs because that was like 3:00 in the morning and I’m like alright, this is nonsense, I need to sleep.

Kelsey: Give me some eggs.

Laura: Right. I did end up falling asleep fairly quickly after that. I know that the fast was definitely impacting my sleep along with some other stress that was going on at that time. The other thing that was weird was it’s been a really long time since I’ve felt like this, but normally I don’t really think about food that much. I eat my meal and I kind of just do what I need to do to feed myself and then the rest of the day I’m not thinking about food.

Kelsey: Mm hmm.

Laura: But on the fast, it was like literally all day I was like, oh my gosh, what is my next meal? What am I eating? Should I snack? Just literally thinking about food all day.

Kelsey: Right.

Laura: Unless I was working, which honestly that was the only time I could really not be thinking about food was when I was working with a client that was keeping me distracted. But I couldn’t do any writing or anything that wasn’t interacting with other people because it was just like all I was thinking about was food. I even would feel like if I was at a grocery store and I was walking past a candy isle or something, I’d be staring at the candy like, oh, that would be so good right now. It’s so weird because I never have that.

Kelsey: Right.

Laura: I don’t think about food like that anymore. I don’t have this craziness around food the way that I might have had. I think this was a lot worse than I ever did in the past, but when I used to be kind of strict low carb Paleo, I used to be a lot less able to eat treats in moderation. I would like not touch them for weeks, and then all of a sudden I would just go crazy and eat so much that I felt ill.

It’s like I haven’t done that in a really long time and I feel like a lot of it has to do with eating enough of certain types of food that make me feel full, and then also not restricting myself as much as I used to.

It was just a really weird experience because on one hand I was like this is crazy. And on the other hand I was like I totally understand why I feel this way because I’m starving.

Kelsey: Right.

Laura: It was weird experience. One other thing that shouldn’t haven’t bothered me but it kind of did was what I actually was gaining weight during the fast. I ended up putting on three pounds of scale weight, which full disclosure, as soon as I had a sushi dinner with eating whatever I wanted the night before, I woke up and all that weight I had gained was gone. It was definitely a weird experience because I was so hungry all the time and I’m like, oh man, I bet I’m losing weight.

Kelsey: Mm hmm.

Laura: I was looking at the scale and I was like this is BS, this is really annoying. Maybe I wouldn’t care so much if I wasn’t getting married in 3 or 4 months, actually more like 4 months, but I was like it’s not fair that I’m starving and that I’m also gaining weight.

Kelsey: Right.

Laura: This is ridiculous. I feel like the experience gave me a lot of empathy for my clients that are dealing with the under eating stuff.

Kelsey: Mm hmm.

Laura: Because like I said I have not felt this way in a really long time. Sometimes I think as a practitioner it’s easy to say this is normal because this is what all my clients experience when they’re doing overly restrictive or calorie insufficient diet for a long time.

Kelsey: Right.

Laura: But it’s like when you actually experience it yourself, honestly I was like I don’t know how anyone functions when they’re not eating enough.

Kelsey: Yeah.

Laura: I know the body kind of like does what it has to do to survive, but I’m just like wow. I don’t know if this is just a sign of like my body protecting against this kind of thing, but I was like I can’t believe how fast I just like fell apart.

Kelsey: Right.

Laura: I was really surprised. I thought a week or two of doing that would not be that hard, and it was like crazy hard.

Kelsey: Yeah. Well I think maybe you have a point there if maybe your body is trying to give you all these signals like, please don’t do this, it’s not right for you. Like it’s telling you that really quickly so that you turn it around. But yeah, I mean I think people feel like this for obviously years and years sometimes for certain people. I think it probably dies down a bit. Like if you had continued this for months or something, maybe you wouldn’t feel quite as bad as you did so immediately because like I said I do think your body is probably kind of trying to tell you something with that immediate reaction. But to think that people feel like this all the time is so sad to me.

Laura: Yeah.

Kelsey: I think it just become this new norm for a lot of people and they don’t even realize that that isn’t normal and that they don’t have to feel like that. I think we end up seeing people who at some point think wow, this can’t be right. I don’t feel good, this doesn’t sound like it should be normal, or I don’t want it to be normal. They come to us and obviously as you’ve seen with many, many clients simply increasing caloric intake and getting a good amount of protein and a good macronutrient ratio can go a really, really long way.

Laura: It was funny because I was doing it with my fiancé and every time we’d have a phone call it would be like both of us were progressing though these stages of like despair basically. The first couple of days we were like, oh this is so hard, I feel so tired, I don’t understand. And then a week in we were like, this is my life now. This is just how things are.

Kelsey: Right.

Laura: It was just funny because I do think you have that initial really strong reaction to it, but if you kind of muscle through it, it’s not that things get better or that you start to feel good or anything, it’s just that you basically feel that well, this is my life now and this is how it’s going to be.

Kelsey: Right.

Laura: It was just weird because for a lot of people the reason they under eat is because they are like overly trying to lose weight, or they’re struggling with that so they’re trying to force themselves into a weight loss scenario, or they are afraid of food so they just don’t want to eat certain things because they’re worried about the health implications.

They’re a lot more motivated to avoid the foods and to kind of push past all that feeling of discomfort to the point where they get to that new normal, like okay well if you’re not going to feed me, I will still function, but I’m going to minimize how well I function.

Whereas for me, it was very bizarre experience where on one hand I wanted to do my best to stick to it so I was like, okay I need to grow up and be able to handle this. But the other part of me was like I really don’t want to be doing this. I don’t like how I feel and I want to feel good. It was a weird experience.

I did have some spiritual benefits that I experienced during the week so it wasn’t just like totally useless torturing myself.

Kelsey: Yeah.

Laura: Which if people want to read about, I do have a blog post on my website that we’ll link to in the show notes about the different things that I learned while doing it. But form a physically health perspective, I definitely learned what it feels like when you’re not feeding your body appropriately and how awful that is.

Kelsey: Yeah.

Laura: Like I said, I think I developed some extra empathy for my clients that are dealing with this on a regular basis where they’re not sleeping well, they feel cold all the time, they are hungry. Honestly, I think the hunger thing starts to go away the fastest, so they may not feel hungry.

Kelsey: Mm hmm.

Laura: But like they’re anxious or just different things that would indicate that they need food but they’re not experiencing the normal appetite regulation.

Kelsey: Right.

Laura: I don’t plan to do that again. Seriously, if I ever do another fast with my church again…because a lot of churches will do that, like on a regular, maybe an annual basis they’ll do a fast. I might do an actual like not eating food for most of the day fast.

Kelsey: Yeah.

Laura: Because I really feel like my body would handle that better than it would handle eating all these high carb, low fat plant foods that kind of just send my blood sugar on this insane roller coaster. So we’ll see. Maybe next year I’ll be less stressed because I’ll be married and none of this wedding planning stuff. I don’t know. I keep saying every year, I’m like next year will be less stressful and somehow it’s just always something going on. But I guess that’s adulthood, right?’

Kelsey: Yeah, exactly. We’ll talk about that idea of stress as we jump into the question here too. I think plays a big role in how people respond to different types of lifestyle or diet changes as well. With that, we’ll jump into our question. But before we do, here is a word from our sponsor:

Today’s episode is brought to you by Pure Indian Foods, a top producer of grass fed, organic ghee products and one of our favorite sources of healthy cooking fats. If you’ve never tried ghee before, it’s a delicious and simple way to get the nutritional benefits of dairy in an easy to tolerate form. The production process removes casein and lactose making a great choice for those who are sensitive to dairy. Pure Indian Foods is your trusted source of homemade grass fed, organic ghee products. The family’s been in the ghee business for five generations and makes their golden ghee with milk from grass fed cows during the spring and fall. Try it today by visiting PureIndianFoods.com.


Kelsey: Our question for today is:

“What do you think about intermittent fasting or other fasts? I’ve heard they can be contraindicated for women especially. If one wants to try fasting, what signs should they look for to know if it’s having a negative effect? Is there a way to fast that would provide benefits but minimize risks? It seems there are potentially real benefits to fasting.”

Laura: Alright. I love that this question just happened to line up super well…

Kelsey: I know it was perfect.

Laura: …with my experience of the “Daniel Fast,” which is just one way that people will do fasting. Obviously we want to talk about the different types of fasting that people have come up with as ways to experience the health benefits. But for those people that don’t really know what intermittent fasting is, I want to talk a little bit about what does that look like and what might be these benefits? Because obviously you don’t want to do something with your diet that is potentially uncomfortable or difficult that isn’t actually going to have some significant benefits.

Intermittent fasting is something that’s promoted by a lot of people in the Paleo community based on some different evolutionary theories where I’d say the real basic thought is that for most of human history food would have been scare and humans would have gone a long time without eating on a regular basis.

The argument is that based on evolutionary theory if humans evolved with this feast and famine kind of food environment, then fasting is something that we’re designed to be able to do and it actually is something like a beneficial stressor. If your body is under the fasting stress and then it responds to that stress, it actually becomes stronger and healthier.

There is actually a significant amount of animal evidence in animals like fruit flies, round worms, and monkeys that intermittent fasting actually helps improve a lot of the body’s functions and actually can potentially lead to longer life span.

I think one of the interesting things as I kind of talked about in the intro is that fasting may be based on concepts of evolution and adaptation to the environment and all that, there are actually a lot of major religions in the world that use intermittent fasting as a spiritual practice. It’s not just fasting is because food is not available, there are actually lots of cultures that practice fasting even if food is available. That includes religions like Christianity, Islam, Judaism, Buddhism, Hinduism, all sorts of different religions that have some level of fasting in their either annual or daily practice. Lots of religions have periods of fasting that line up with certain holidays. There are some that have weekly dietary restrictions that imitate this type of fasting behavior.

Fasting and intermittent fasting doesn’t really have a specific definition, but at a minimum I would say it requires regular periods of fasting or food abstinence in your normal meal schedule. Whether that’s skipping a meal or skipping a whole day of food, there’s lots of different ways to do it. I know when we interviewed, well actually we don’t have this interview up yet, but we were interviewing Ben Greenfield and he talked about how he actually usually does a full day of fasting on Sundays. You’ll hear about that next week. But that is something that has been recommended by a variety of different people. The most popular one I’ve seen has been the “Eat Stop Eat” method which was created by Brad Pilon. He has that 24 hour plus fast that he recommends.

Kelsey: Mm hmm.

Laura: Other people tend to promote that daily 8 hour feeding window style of fasting. People like Paul Jaminet and Martin Berkhan who created the “Leangaines” program. They typically recommend that you fast for 16 hours of the day and then have an 8 hour feeding window where you’re eating. Then there’s also “The Warrior Diet” which is one that shortened that window even tighter so you have less time to be eating a lot. They have a 4 hour overfeeding window. I say overfeeding because part of it is you kind of like stuff yourself during that time.

Kelsey: Mm hmm.

Laura: I’m not super familiar with “The Warrior Diet,” but from the research that I did before the show, it looks like the fasting period for “The Warrior Diet” is not necessarily 100% food free. There are some things that you can eat. I think it tends to be lower calorie things like plant foods. But the goal is to get the majority of calories into that 4 hour feeding window.

Kelsey: Right.

Laura: Those are just 3 of the more typical fasting methods. With the “Daniel Fast”, that is something, actually I don’t know a ton about organized Christianity, but I’ve seen on Chis Masterjohn’s site talking a little bit about their fasting practices. They’ll do I think 2 days a week that’s pretty much vegan.

Kelsey: Mm hmm.

Laura: That could maybe be considered a fast as well because of the protein restriction. There’s lots of different techniques and none of them are necessarily the perfect way to do it, but a lot of them do have the same benefits.

Are there any fasting methods that I haven’t mentioned that you’re aware of, Kelsey?

Kelsey: I don’t think so, but I was actually just wondering, thinking about it if I would consider somebody doing a vegan fast as a true fast in the sense that it would maybe have the same benefits.

Laura: I think with the vegan fast or actually even with something like Bulletproof fasting which includes the fat containing coffee as part of the fast, it’s really the protein restriction that’s creating the biggest benefit. Now that’s for…actually I should rewind for a second. And I want to talk about what the benefits are, but the main benefit that gets promoted is something autophagy. It actually means self-eating and autophagy is a process that allows your body to clean up extra or damaged parts of the cell, or if there’s any pathogenic bacteria, or viruses, or yeasts in your body that the immune system can go after and scavenge I guess parts from.

Kelsey: Mm hmm.

Laura: In Wikipedia, they define it as “the natural regulated destructive mechanism of the cell that disassembles unnecessary or dysfunctional components.” The theory is that if your body is destroying those dysfunctional or unnecessary cellular components, then the cell actually ends up working better because it recreates new components that are more effective and more functional.

Kelsey: Right.

Laura: The autophagy I would say does require protein restriction to encourage that because it’s really those damaged proteins that body starts to scavenge during the autophagy process. Whereas not eating at all or doing a protein sparing modified fast where you do eat protein but you basically don’t eat anything else, that actually I think has more to do with fat loss.

Kelsey: Right.

Laura: That’s more about energy restriction and needing the stored body fat to provide the energy, whereas the autophagy has more to do with protein restriction and not having enough protein to do what the body’s natural function is where it’s creating enzymes or going through metabolic processes that use proteins as part of that process. If they don’t get enough protein in the diet, it’ll scavenge those damaged parts of cells or pathogens that it can then use those proteins in a normal function.

Kelsey: Gotcha.

Laura: That’s my understanding. I could be wrong. Certainly I’ve been wrong before. But from what I know about human biology and the way that our macronutrients impact the use of different individual amino acids, and fatty acids, that kind of thing, I don’t really think the body would use body fat to deal with a protein restriction as much as it just uses body fat for calories.

Kelsey: Right.

Laura: The protein restriction is the benefit. With vegan fasting, unless you’re doing tons of soy and other plant proteins, then you should be in that protein restricted state and then your body will start to use those damaged proteins to support its normal function.

Kelsey: Yeah.

Laura: That’s my understanding. I think intermittent fasting, the benefits do range from that autophagy which tends to be the one that is more focused on. And then also it can be really helpful for fat loss and for metabolic function. The actual calorie restriction part of it has its own benefits and I do think that can make the autophagy a little bit stronger if you’re also in a calorie deficit.

Kelsey: Mm hmm.

Laura: But you don’t have to be in an actual severe calorie deficit or just completely eat nothing to get that autophagy experience. That’s one reason why a lot of people promote plant based protein restricted diets for longevity because they feel that that promotes that autophagy process on a long term.

Kelsey: Mm hmm.

Laura: I don’t know if that is super well supported. I think one of the problems with that is that even if it does help with longevity, I think from my experience during the fast I did, I think quality of life could potentially suffer depending on what your lifestyle habits are and that kind of thing. But there might be some evidence that lower protein intake can help reduce the aging process.

Kelsey: Mm hmm.

Laura: Some of it also with that autophagy I think helps with inflammation and also modulating immune function. It’ll kind of boost immune activity to get that scavenging process happening, but it also helps get rid of proteins that are maybe causing some damage or contributing to inflammation.

If somebody’s got an autoimmune disease or some kind of an inflammatory issue, which cardiovascular disease tends to be an inflammatory issue. Cancer I think there’s a lot of theories about what cancer actually is, but there is definitely some inflammation and immune dysfunction involved there as well. That’s one of the reason why they believe fasting can be beneficial for certain chronic diseases. Certainly diabetes could, and I would say type 2 diabetes, we put that under there that that would be benefited from the hormonal changes that will happen during fasting.

Kelsey: Mm hmm.

Laura: Certainly would benefit insulin resistance. But there’s a lot of chronic diseases that can be benefitted by fasting. Like we were saying before, the weight loss side of things, just being in a calorie deficit is going to promote weight loss.

Kelsey: Right.

Laura: We’ve talked a lot about calorie deficits in the past where we don’t want to be overly dropping calories and certainly fasting nonstop is not a good idea. But there are some people who really do find that it’s easier for them to pick a couple days during the week where they under eat, and then the other days they get to eat what they want, and the overall week there’s in a calorie deficit and they can see some weight loss without it being every day that they’re on a diet.

That does potentially help with some of those hormonal problems that come from chronic under eating. If you’re having some days that are low calorie that you’re tapping into your body fat stores, and then you’re having some days that are high calorie and kind of promoting the parasympathetic nervous system and calming down any sort of stress hormones, that could potential be a long term strategy for weight loss for people who are overweight or obese.

I would actually say that if you can go several hours without eating or if you can tolerate fasting and feeding window type suggestions, that that’s actually a sign of good health in general. When I have clients or if I’m in a state where I can’t tolerate not eating, I can kind of pin point what’s the problem. Maybe it’s a lot of stress in their lives or they’re just not eating enough during meals, or they’re micronutrient deficient.

Kelsey: Mm hmm.

Laura: But basically if somebody’s is healthy, skipping a day worth of food shouldn’t send you into a tailspin, or skipping breakfast everyday shouldn’t be a problem.

Kelsey: Right.

Laura: If you’re noticing that fasting is really hard or you can’t go more than a couple hours without eating, then there’s definitely some issues that we’d want to figure out.

Kelsey: Yeah, I agree. I think that probably one of the other benefits that people tend to say is great about fasting is being able to switch between fat and glucose more easily. That’s known as metabolic flexibility. I think that tends to be something that people tout as a benefit as well. I think that’s sort of what you’re tapping into here with that ability to go several hours without eating as a sign of good health because generally that means that you’re able to switch between glucose and fat more easily, you can go 16 hours or even 24 hours without eating no problem because your body can just tap into fat stores and provide fuel from there.

Whereas somebody who is generally really thriving on glucose most of the time, they’re going to have in general a little bit of a harder time tapping into that and becoming more metabolically flexible in times where food isn’t available. With all that being said, I think it definitely makes sense to go into some of the drawbacks here.

Laura: Yeah.

Kelsey: I wouldn’t necessarily say that all these things I’m going to mention are drawbacks because really what I want to point out most is that when it comes to intermittent fasting, a lot of the same benefits can just be seen from simple caloric restriction as well.

Like you were saying before for a lot of people it just tends to be easier to be in a caloric deficit if they’re intermittent fasting because they can do exactly what you said, they have a couple days where their intake is a lot lower than normal and then other days where they eat what they would normally eat and that equals out over the course of a week to being a deficit.

But one of drawbacks I would say is that it can be really easy to under eat too significantly. I think if you’re going to do intermittent fasting and you want to get the most benefit out of it without getting some of the drawbacks that we’ll talk about in a second is that you really should I would say track your calories at least as you start to make sure that your only getting a slight caloric deficit to make sure that you’re not going to get some of these more major drawbacks that you can potentially get from eating at way too much of a deficit.

We’ve talked about calorie deficits and too large calorie deficits and the problems that can come about from that in some of our past podcasts. But just to recap here, under eating definitely has a lot of problems. It can certainly cause problems with hormones, mood issues, losing too much muscle mass instead of losing mostly fat mass if you’re trying to lose weight. Those excessive caloric restriction problems can absolutely apply to intermittent fasting as well if you’re not careful about only being at a slight caloric deficit when you’re intermittent fasting.

I would say being at a more significant caloric deficit while you’re intermittent fasting is an easy trap to fall into. I’ve definitely had clients who as I’m going through their food diaries and talking to them about what they’re eating while they’re intermittent fasting over the course of the week, I can clearly see that they are severely under eating and it’s no wonder to me at that point that they’re not feeling great. Whereas if they were maybe doing intermittent fasting at just a slight caloric deficit, they might feel totally fine.

Laura: Right.

Kelsey: It’s a great way to do a sight caloric restriction if that’s easier for you to maintain.

Laura: You’re not just talking about day to day calorie restrictions. You’re talking about I would say an average.

Kelsey: Right.

Laura: There may be a day that you’re eating 1,000 calories less or 2,000 calories less if you’re not eating at all for a full day than what you would normally eat. But if the rest of the week is eating more to make up for that, then maybe the average calorie deficit for the whole week ends up being like 500 calories per day if you split that across 7 days.

Kelsey: Right.

Laura: That’s something to keep in mind….For example, the 24 fast option, yeah, you’re going to be like 2,000-3,000 calories too low that day. I know like I said we interviewed Ben and we’re going to talk to him next week. But if his calorie needs are like 3,000-4,000 a day and he goes a day without eating, yeah, he’s 3000 calories too low that day and that sounds like a lot. But if you split that out across that whole week, then it’s only potentially like 400 or 500 calories a day and then he may eat a lot more than that on those other days so then it makes it even potentially not even an average calorie deficit at all.

Kelsey: Exactly. I think if you are thinking about intermittent fasting as a way to help you maintain a caloric deficit, I certainly think there’s a lot to be said for that idea and I think it can work well for a lot of people. But like I said before, at least maybe for the first week or two, I would do some calorie tracking to see what your caloric intake ends up looking like over the course of the week so that you can tell if you’re eating enough or if you’re at way too much of a deficit because obviously under eating like I said can definitely have a lot of problems.

In addition to that note here, I would also say that the idea that, I actually forget if you mentioned this or not, Laura. But one other thing that I tend to see with intermittent fasting as a touted benefit is that it can maybe preserve more muscle mass when you’re trying to lose weight than simple caloric restriction does. But what you see in the studies is that basically it’s the same. The amount of muscle mass that you preserve while losing weight is the same whether you are restricting your calories or you’re intermittent fasting provided that your protein intake is the same.

So really it’s protein that makes the most difference in terms of how much muscle mass you’re going to maintain while losing weight. If you’ve seen that as a benefit, I would say that that’s not necessarily a benefit of intermittent fasting. It’s just a benefit of eating enough protein while on a caloric deficit.

Laura: Right. Yeah, and that’s the protein sparing modified fast approach.

Kelsey: Right.

Laura: Which again won’t have the autophagy benefits per se, but if you’re mostly just looking to lose weight, then there’s really no need to also be doing autophagy at the same time.

Kelsey: Right. I’ll link to a scientific article in this podcast in the show notes which is basically an overview of the benefits and detriments of intermittent fasting. It’s a really interesting article to take a look at. It goes through a lot of different studies that have been done on intermittent fasting and caloric restriction in general and kind of compares everything.

To me what stood out as the result of reading this article was that essentially a lot of the benefits that you get from intermittent fasting can be seen through caloric restriction as well. The other thing that you may hear is that it helps you maintain the weight that you lost if you intermittent fast versus feeling like you have to constantly be on a calorie restricted diet. That may be more of a mindset thing that if you really feel that skipping a day of eating makes maintaining your weight a lot easier because you’re in a caloric deficit, fine. Yes, it does as long as you’re maintaining a slight caloric deficit or eating at maintenance once you’ve lost the amount of weight that you want to lose. But the same can be said of course for just a chronic maintenance calorie diet or a slight caloric deficit if you’re still trying to lose a little bit of weight but potentially maintaining there.

But basically again, equal footing in terms of intermittent fasting as far as caloric restriction in that regard. There’s no real benefits of intermittent fasting on maintaining weight that you have lost. It’s just you need to eat maintenance calories and if intermittent fasting helps you to do that and helps you to not overeat, then you’re going to have the same benefit that you would if you just kept at maintenance calories every day.

Laura: Mm hmm.

Kelsey: The other thing is that for overweight and normal weight people, there seems to be a very big difference. I think that’s probably where most of the studies that people are pulling to tout the benefits of intermittent fasting are actually coming from because of course right now that’s what a lot of the studies have been done on are people who are overweight or people who have diseases like type 2 diabetes where they have metabolic diseases that from a theoretical standpoint you can imagine why somebody like that would do better with intermittent fasting.

We definitely see a difference between overweight and normal weight people, especially for women I would say for normal weight. And we’ll talk about this in a minute a little bit more, but definitely for overweight people you tend not to see as many of the detriments I would say in terms of hormones because essentially you are correcting an overweight situation which helps a lot of health issues and can actually improve hormone balance for people. In that sense, there is definitely a benefit to fasting. But if you’re of normal weight, you can certainly more easily jump into that under eating category where again you would see all of those under eating problems that come about.

But that said, for both overweight and normal weight people there are some issues. I would call them side effects I guess of intermittent fasting which include things like sustained hunger, just feeling hungry all the time especially on days where you are intermittent fasting. Then for those alternate days of the fast where you’re skipping a day of eating entirely, studies definitely show that people have trouble doing their normal daily activities. Laura, I’m sure you can speak to that a little bit. We definitely heard that even on a modified fast where you’re still getting calories but you have this chronic…actually did you track your caloric intake? Do know if you were under eating?

Laura: Honestly, I didn’t track, so I have no idea. But I will say that I was eating 5, 6 times a day.

Kelsey: Okay. So maybe you weren’t at a caloric deficit necessarily.

Laura: It’s honestly hard to say because it’s possible that I still was.

Kelsey: Mm hmm.

Laura: But I have no idea. I was literally eating as much as I could as often as I could.

Kelsey: Gotcha.

Laura: I wouldn’t be surprised if my calories weren’t that much lower than they normally are to be honest.

Kelsey: Yeah, okay. In the case of intermittent fasting, especially those alternate day fasts, I’m sure you can imagine if you skip a day of eating entirely, a lot of people generally are not going to feel as great doing their normal daily activities. I think that’s an obvious sign that potentially it could not be great for some people especially if you’re not choosing the right day to do that.

If you end up choosing a stressful day at work and you’re not eating simply because maybe it’s easier because you’re so busy or something, I think a lot of people will tend to do stuff like that where they just stick to a certain day every week that they fast and it may not be the right day for them to do something like that. I think that definitely can have a negative impact on just being able to function in everyday life.

That’s sort of what the studies show at this point especially I would say in normal weight people. But even in overweight people they see the same thing. I would say in that sense you can probably combat that sort of issue if you pay attention to what day you’re choosing to fast and making sure it’s a low stress day, maybe that you’re not doing any intense exercise, stuff like that. I think you can still get a lot of the benefits from fasting without really kind of ruining your ability to function.

But again, you have to pay attention to it. We are not living in a hunter gatherer world anymore and we have different stresses and things going on all the time that I think can negatively impact the benefits of fasting if you don’t do it right.

And then lastly I’ll bring up this point in terms of the drawbacks which I think applies more to people potentially a history of eating disorder, or things like that, or just a bad relationship with food. I think it can sometimes to be used as an excuse to under eat without kind of admitting that that is the purpose. I’ve definitely seen that before in my clients as well and it’s something that if you have a history of that, you really need to pay attention to what’s going on with you and whether you think that that you’re using it as a reason to under eat and thinking that it will help your health when in reality because of your history and because of the way you currently think about food, it just probably just won’t be very helpful.

Then on that same note, if you are somebody who just has an inherent preoccupation with food, you think food a lot, maybe still you have a history of eating disorder or something like that, but you feel like for the most part you’re over it, but you’re still thinking about food a lot, it’s just something that’s on your mind, I do think that fasting in that case can be problematic only because it will tend to increase cravings for food, it will tend to increase the amount of time that you spend thinking about food, and you may end up sort of almost binging on foods once you come out of that fasting period. And that can just create a cycle that is not healthy for some people if you are not thinking about food in a good way and you don’t have a great relationship to food to begin with.

I would definitely caution people who have any history of eating disorder, or bad relationship with food, or bad relationship with their body to check in with themselves and make sure that you’re not just using this as a way to further restrict your eating patterns.

In that scenario if you’re not sure or if you have a history of that and you are thinking about doing something like this, I would also recommend that you talk to a dietician or a psychologist, somebody who can kind of look at the whole picture here and say whether it might be appropriate for you or not. Because like I said I’ve seen this a lot where people come to me, they’re like I think I want to intermittent fast. And after talking to them I can clearly see that it’s only going to cause them problems.

Laura: Right, yeah. I think anytime you’re experiencing those kind of thoughts around food before you even start the fast, that’s probably a good sign you shouldn’t try it.

Kelsey: Yes, exactly, exactly. I think in terms of just everybody when it comes to fasting, I guess I wouldn’t say there’s a ton of actual drawbacks because I do think that fasting can be helpful. But like I’ve said, based on this scientific research that I’ll post for you guys, there just doesn’t seem to be a whole lot of benefit over just simple caloric restriction.

If caloric restriction on a daily basis is easier for you to maintain and you’re trying to lose weight or you’re trying to get some of these benefits, I think that’s potentially makes more sense. And then if you want to kind of tap into the benefits of autophagy, maybe you do some cyclical protein restriction to tap into that. In general, I don’t want somebody on a caloric restriction really long term.

I think it’s useful, but from what I’ve seen, it does not necessarily have as many benefits as you would think from all the articles and everything that are out there about intermittent over the benefits of just a simple caloric restriction.

Laura: Right.

Kelsey: Okay. Let’s talk a little bit about fasting for women because I do think that this is a little bit different than just fasting for men. The reason why is because there’s not a whole lot of research on women with fasting, unfortunately. But from the research that we do see, women tend to not respond to fasting as well as men do.

I think there’s definitely something to be said about this overweight versus normal weight idea especially when it comes to women because we do see that women who are significantly overweight seem to do better with fasting in the research that we do have available. There’s really not a whole lot of research on normal weight women and intermittent fasting, but from animal models we can see that there’s some not so great results that happen as a result of that.

When I say not so great results I mean that I would say that probably the thing you’d notice more immediately if you are a normal weight woman and you’re trying to do intermittent fasting is that you will potentially, as they see in research, experience a lot of hunger, your mood will get worse, they’ve shown heightened irritability, difficulty concentrating, increased fatigue, a lot of eating related thoughts, and fear of loss of control and over eating during non-restricted days.

This is something that I have certainly heard from my women clients who are of normal weight who have tried to do intermittent fasting. I can say from second hand experience through my clients that this is really, really common. I’m sure, Laura, you can say the same.

Laura: Yeah, definitely.

Kelsey: Yeah. I think that these more immediate effects of just essentially feeling like crap are definitely a problem for women especially and even more so if you are a normal weight woman. You really need to think about that. I would say again that this is probably true simply with a more significant caloric restriction if you’re of normal weight, and you’re a woman, and you don’t need to be on a caloric deficit.

I don’t know if they talked about that in this article that you guys will see, but I would imagine that it’s kind of the same because again, Laura and I work with a lot of women who tend to under eat and these are the exact kind of symptoms that we would see in a person like that as well. I’m not sure if this is only because somebody is fasting. It may just be because somebody is on an accidental caloric restriction when they’re tending to fast.

Laura: Mm hmm. I mean with human studies it’s always really hard to be super well controlled, so there could be things in the person’s history that make them react differently that even if they’re not under eating now, maybe they had a history of under eating. I feel like anytime you’re doing humans that they’re going to be a lot of room for error where you can’t control for it even if you wanted to.

Kelsey: Right, exactly.

Laura: Really this is just kind of just explaining why if you are going to do this kind of stuff you need to just give yourself the priority as far as if something is not working for you, it doesn’t matter whether it works for 99 other people.

Kelsey: Mm hmm.

Laura: If it’s harming you, then you shouldn’t be doing it.

Kelsey: Yeah, exactly. With normal weight women in particular, they have also seen that it can potentially… and this is a little bit up for debate, it hasn’t been proven in a lot of studies at this point…but that for normal weight women it can potentially lead to insulin resistance.

Certainly not something that you necessarily want, of course, but the idea is that it might actually be more of a protective mechanism because it’s actually peripheral insulin resistance where you’re muscles won’t be taking up glucose.

That does make sense just because your muscle don’t want to take up glucose that your brain needs and other organs that really need that glucose more in a time of starvation or fasting. I think that potentially makes sense in the context of things. But it’s unclear if that over the long term could really lead to something that’s not so great.

Laura: Mm hmm.

Kelsey: But in general, I’d say probably the worst effects of fasting on normal weight women are going to be those side effects I just talked about like the hunger, worse mood, irritability, all that. The hormonal issues that go along with under eating, which we’ve talked a lot about so I’m not going to re-cap that in detail here, but definitely it can lead to issues like hypothalamic amenorrhea if you’re significantly under eating, you’re over exercising. Problems with your menstrual cycle and problems with fertility, which of course you don’t want. It’s not a good sign of health.

I think as somebody who is a normal weight woman should really think twice about fasting because not only are you going to feel like crap, but it also is going to have potentially a negative impact on your hormones.

Laura: Yeah. It’s kind of funny with the church fast. I don’t know if I just wasn’t talking to the guys as much, but it did seem like the girls that were doing it were having a lot more trouble. Just anecdotally for whatever reason it seemed like the men that we were doing this fast with were tolerating it better. I don’t know what the reason for that was. Obviously there are sex differences in fasting tolerance.

Kelsey: Mm hmm.

Laura: But it was just interesting to see how, like my fiancé would tell me what he was eating and I’m like how are you still standing? He’s 6’4” and 200 pounds and he’s like oh I had a potato, and some vegetables, and a banana for dinner. I’m like I can’t even eat that. I would be like dying. I imagine there’s got to be some kind of explanation for why women would react more poorly to fasting than men.

Kelsey: Mm hmm.

Laura: But it was just kind of funny to see that because on one hand it was little annoying because the girls were trying to keep up with their significant others doing the fast. They were just like this is terrible, I can’t do this anymore! I’ve definitely see that anecdotally that there is a significant sex difference.

Kelsey: Yeah. I’ll say that from the research I’ve seen, honestly because of the lack of research on normal weight individuals and especially normal weight women, we honestly just don’t know at this point if it’s safe or not especially over the long term because there’s just not enough research unfortunately.

I would say given these more short term effects that you see especially in normal weight women who are fasting or on some sort of caloric restriction unnecessarily, certainly I would recommend exercising caution in doing something like that because we can kind of see just from the symptoms you get when you do that that it’s probably not a good idea, especially over the long term.

Laura: Mm hmm. Definitely. Did you want to say anything else about sex differences, or should we talk about how to actually fast now that you guys know what the kind of pros and cons are?

Kelsey: I guess the only other thing I’ll say is that the studies do show…we talked about worse mood and thinking about food a lot and all that kind of stuff that can happen in normal weight women. What the studies show now is that for women, and I think actually just people in general who are overweight or obese, when they do intermittent fasting they actually get benefits in those categories. Their mood improves and eating behaviors improve.

That’s a real interesting note to make about the difference between normal weight and overweight people because again, honestly I think that may be even a bigger divide in this fasting question, like who it’s right for. I think it can definitely be much, much more useful and potentially have a whole lot of benefits for somebody who is overweight or obese especially as a woman considering doing something like this. If you’re overweight or obese, you’re not going to see nearly as many problems with intermittent fasting as somebody as who is of normal weight.

I think that actually may be a bigger piece of this whole puzzle is we need to really make sure when we’re doing this research, like who are we talking about here? Are we talking about somebody who is of normal weight or are they overweight? Then the gender piece of course comes into play as well. I think it’s just amplified in that sense.

Women who are of normal weight are going to do much worse than a man who is of normal weight. But I do think that anybody who is overweight or obese, whether they’re man or a woman, the research does seem to point that there are definitely benefits in that case.

Laura: Cool. Now that you guys see different things to consider with your fast, now we can talk a little bit about what you actually want to do with a fast because like we said a little bit earlier in the podcast, there’s many different suggestions on what to do and there’s not necessarily one right or wrong way to do intermittent fasting.

I feel like the main question to consider when you’re thinking about doing a fast is: 1 – How will it fit into your schedule? And 2 – How will it affect your health?

The schedule piece I feel like is really important for sustainability because if you’re trying to do a fast that really doesn’t work with your schedule or makes it difficult to do the things that you need to do on that day, then it’s unlikely that you’re going to stick with it.

One example is the breakfast skipping type of fasting. Some people actually really like that because it takes one meal out of their daily meal planning and saves them time in the morning. It’s really easy to for them to do, they don’t really miss it, and they can eat more at lunch and dinner to make up for missing that meal. But for some people that might not work. Maybe they workout in the morning or maybe they don’t feel good if they don’t have breakfast so doing breakfast skipping on a daily basis could be not so sustainable for them.

Then there are some people that like to do that occasional 24 hour or full day fast. It might be because they’re active and they feel better eating higher calorie amounts on the days that they’re working out and on the days that they’re resting, they feel that they’re able to either go the full day without eating or have a very low calorie intake.

There’s some schedule type of things to consider and then also we were saying how the health impacts will actually drive some of the decision making process too. You could look at those two same fasting options and say well, skipping breakfast doesn’t really bother me. I can get through it, and I don’t really notice an issue, and it’s only a couple hours of not having food, it doesn’t really derail my mental function or anything like that.

Kelsey: Mm hmm.

Laura: Whereas the full day fast may be something that really does cause a lot of that preoccupation with food, or brain fog, or just not feeling well. Those two different options are going to fit people differently.

With making that decision, there’s so many different factors so I don’t want to say like this is the x, y, z factors that you should choose this fast for or that fast. But I would say if one seems to feel like a better choice for you, then just try it out and see what happens, and see how you feel, really just thinking about choosing a method that’s going to make your life easier as opposed to harder. Like I said, if skipping breakfast makes your life easier and you don’t mind missing that meal, then it might be a good strategy for fasting.

Personally I’ve actually tried both the 24 hour fast and that 8 hour feeding window type fast. I find that I can’t actually handle that 24 hour fast.

Kelsey: Yeah.

Laura: I end up thinking about food all day, feeling crazy. It’s not even that I’m super hungry, it’s that restricting the food for the whole day just feels so weird that I can’t do it.

Kelsey: Mm hmm.

Laura: Even if it’s the way that Brad Pilon recommends doing a stop eating at noon and then start eating at noon the next day, so you technically do eat on those days.

Kelsey: Right.

Laura: But even doing that, I don’t know what it is. It just feels so weird to me and I can’t really function very well.

Now if I do that 8 hour feeding window, I actually don’t feel too bad. I can handle it especially if I eat enough during the feeding window itself. I feel like with that approach, sometimes I do that accidently even though it’s not a strategy that I’m currently using. Especially on the weekends, if I am busy and I’m not necessarily feeling like cooking as soon as I get out of bed, sometimes I don’t eat until 1:00 or 2:00 in the afternoon and I’m okay because I’m not under a lot of stress the way I am during the week. Maybe I slept in a little bit and it just doesn’t bother me.

Certain types of fasting I feel like for me works better than others and that’s part of that experimentation process where you actually figure out what works for you. Even if you try something out and it doesn’t work, that doesn’t mean that it’s a bad idea for somebody else. It just means it’s not going to work for you.

Kelsey: Right. The research in general, like I was talking about before, does show that the ability for people to stick to some sort of fasting regimen definitely decreases when you get to that 24 hour fast or that alternate day fasting schedule. I’d say if you’re newer to fasting and you just want to try it out, I would not necessarily just jump into that. You might want to try something a little bit smaller first, work your way up to a 24 hour fast, see how it feels for you.

Like we’ve been saying, if that ends up working better for you, then cool. But if not, and the research does show that most people are probably not going to do best with that kind of fasting, don’t worry about it. You can still get a lot of the benefits doing it in a different way.

Laura: Mm hmm. Now as I mentioned in the beginning of the podcast, fasting doesn’t necessarily mean 100% food elimination and that you’re eating absolutely nothing. There are different techniques for fasting that still do involve food. As I was mentioning, the fasting that we were doing was just plant foods and so it’s not like you’re not eating anything, you’re just avoiding certain foods.

Paul Jaminet who is the author of The Perfect Health Diet book, and I work with his public health retreat so I know a lot about his strategies that he recommends, he often suggests consuming some bone broth with veggies especially things like tomato and other potassium rich vegetables and some salt to make sure you’re getting electrolytes balanced during the fast which I think imbalanced electrolytes can cause a lot of those symptoms people can experience.

There’s also that Bulletproof fasting technique that people do a lot. Basically it’s coffee with several tablespoons of butter and coconut oil in there that’s blended up. That I would say is more of a protein fast than an actual fast because if you’re using four tablespoons and coconut oil, then you’re getting 500 calories from that so it’s not really a low calorie intake for that specific recommendation.

Now I don’t know if I like the idea of people getting that much fat in the fasting period unless they’re really active. Often times if I have somebody that wants to do some Bulletproof fasting they can try cutting that fat down to like one or two tablespoons so they’re still getting the calorie restriction benefit. Because otherwise like I said if you’re getting 500 calories of pure fat in coffee in the morning, that’s not really going to make getting into a calorie deficit very easy.

Kelsey: Right.

Laura: You wouldn’t want to necessarily totally eliminate the calorie deficit benefits because I question whether or not that really has the same outcome as something that involves that calorie deficit.

Again, you can have some fat, you can have some salt and electrolytes, maybe you do have a little bit of protein if you’re really feeling like it’s not working to eat nothing. But the goal is to either be low protein, or low calorie, or both.

And then as far as troubleshooting goes, I would say if you have adrenal issues or if you have caffeine sensitivity, I wouldn’t do that Bulletproof fasting approach. I have a lot of clients with HPA axis dysregulation who feel really bad if they have a lot of caffeine with their fast because it amplifies the stress hormone response. Maybe do decaf, or just skip the coffee and just do some hot water with coconut oil in it or something if you need that coconut oil, or just take a spoonful right of the spoon. But the caffeine thing just can amply a lot of those adrenal responses to fasting.

Same kind of goes for that blood sugar control issue. If you don’t have good blood sugar control, first of all I’m questioning whether or not fasting is actually a good idea.

Kelsey: Mm hmm.

Laura: But if you are going to try fasting, make sure that when you are eating that your meals contain a lot of protein, that they’re also providing fat and carbs when you’re not fasting. You want to make sure that you’re eating lots during the feeding window so that way you have plenty of food to run on in the fasting window. For those people with blood sugar issues, you might actually want to try doing those less intense fasts where you’re only avoiding food for a few hours a day rather than all day. So that 8 hour feeding window might be a better choice for someone with blood sugar issues. And again, if you’re getting a lot of fluids and electrolytes, it can make the fast a little easier. If you’re doing a full day fast, you might want to do that bone broth with veggies in it to get the electrolyte balance.

Something else to consider when you’re fasting is I don’t really recommend any sort of intense workouts on a fasting day. It’s not that you shouldn’t move at all or that you need to lay on the couch all day  to tolerate it, but don’t do CrossFit or high intensity weight training, or lots of sprinting, or long distance running if you’re on a fast day. Try to stick to the lower intensity movements like walking, gentle cycling, maybe some yoga that’s not too intense. Because some of that general movement can actually get those fatty acids from your fat stores released. If you’re doing this to lose weight, it’s actually better to do some of that movement during the fast.

Kelsey: Mm hmm.

Laura: But I wouldn’t do any of that hardcore high intensity type workouts on a day that you’re fasting. Or say you do CrossFit and you do it in the morning, you probably don’t want to be doing a type of fast where you skip breakfast and maybe don’t eat after that workout for like 4 hours or something.

Kelsey: Right.

Laura: And then for a lot of women, they don’t do as well on the longer fasts even if it’s that 8 hour feeding window type of fast. A lot of the people who recommend those fasting windows, they’ll actually suggest that women expand their feeding window to 10 hours. Both Paul Jaminet and Martin Berkhan from “Leangains” recommend this adjustment. That would mean instead of it being a 12 pm to 8 pm feeding window, maybe you do it 10 am to 8 pm feeding window.

Kelsey: Right.

Laura: Unless you’re waking up super early, I don’t think it sounds that crazy to eat between 10 am and 8 pm, or maybe it’s 9 am to 7 pm.

Kelsey: Mm hmm.

Laura: But for a lot of women they do better with that. Then if you are training a lot, if you’re doing CrossFit, or powerlifting, or any of those type of high intensity glycolytic type activities, then try to eat higher carb meals on the days that you do workout or the meals before your workout, so if you work out in the morning, try to have a lot of carbs at night. That way you’re supplying glucose for the workout and then you can eat carbs post workout, you’re also refilling your muscle glycogen stores. It can kind of help prevent those blood sugar swings that happen when you’re not getting enough glucose to support your activity.

Then another suggestion that comes from a guy named Tim Ferriss who has a book called The 4-Hour Body where he recommends fasting, he did a lot of experimentation with fasting and he discovered that having a couple of days either one or two days a week where he has like a feast day where he just eats as much as he can while still being in that general calorie deficit across the week, he actually felt like that prevented some of that hormonal imbalance or possible harm that comes from chronic calorie restriction. And this guy Tim Ferriss actually said that…so his fast was for fat loss and he felt like having that feast day once a week was actually helping to lose more body fat because he wasn’t getting into that metabolic I guess suppression that a lot of times calorie restricted diets will cause.

Kelsey: Mm hmm.

Laura: A lot of people do a cheat day because they think it’s helpful for sustainability, but there may actually be some benefit to that feast day just from a metabolic perspective and it doesn’t just have to be a psychological benefit.

Kelsey: Yeah.

Laura: But I would say anytime anyone is going to do any fasting, if they have any sort of major chronic illnesses, they should first of all definitely talk to your doctor before doing it. There are some illness that I think would benefit from fasting, things like small intestinal bacterial overgrowth I think can be a really great condition to do some fasting with.

Kelsey: Mm hmm.

Laura: Then also autoimmune disease I’d say there is some practitioners will do more of a fasting type approach with autoimmunity which could be helpful. There’s certain conditions that maybe are even better for fasting. But then there are some that we’ve mentioned that may not be good for fasting. For example, if you’re a woman with hypothalamic amenorrhea, you shouldn’t be doing fasting.

Kelsey: Mm hmm.

Laura: If you have reactive hypoglycemia you probably shouldn’t be fasting right now. If you have any sort of chronic illness, don’t do this without being supervised because it could actually cause more problems than it solves.

Kelsey: Yeah. I would add to that too that even if you have an illness that might benefit from fasting but you’re also either under a ton of stress or you know you have HPA axis dysregulation or “adrenal fatigue,” you really need to weigh the benefits there because that condition, HPA axis dysregulation certainly in general I would say does not suit fasting very well. As a general blanket statement I’d probably say that if you have HPA axis dysregulation and some other condition that can potentially benefit from fasting, I’d say you still probably should not fast.

Laura: Mm hmm. Definitely. Even if you’re working with someone, you do want to be paying attention to symptoms. There’s probably going to be an adjustment period. You’re not always going to feel like you’re on unicorn fuel the first day that you’re doing a fast. But if you’re doing it for a period of time and you’re constantly having negative side effects like headaches, or serious fatigue, feeling really cranky or anxious, if you’re experiencing brain fog that’s detrimental to your ability to do your daily activities, if you’re having a really hard time tolerating exercise, you’re not recovering well…

Kelsey: You’re not sleeping well.

Laura: Right.

Kelsey: Put that one in there.

Laura: Definitely. If you can’t sleep through the night or you can’t fall asleep until 3:00 in the morning, it’s probably not a good sign. I would say that that could be a sign that you need to either shorten your fast, so if you’re doing that 8 hour feeding window, maybe do the 10 hour feeding hour. Or eat more when you’re not fasting, so just make sure you’re getting enough calories when you’re eating so that the fasting is not as challenging.

Kelsey: Mm hmm.

Laura: Or just stop, don’t do the intermittent fasting because it’s potentially not the best time for you. It could just be seasonal. There are definitely seasons of life that are more challenging and that fasting might not be a good idea.

I know I’m elbow deep in wedding planning and trying to get all of the things figured out with family and friends and coordinating all that stuff and that’s kind of like the not fun part. That’s been being under that level of stress I think can make fasting for me even challenging. Whereas if I was pretty low stress, was feeling pretty chill about how things were going, then doing some fasting would maybe be healthier.

It could also just be a day to day basis thing. Like I said, maybe the weekend is a day that I do a couple of fast type days whereas the week days I don’t because I’m under more stress with my work week. I think this was something I really realized during my “Daniel Fast” because of all the stress that I’ve been under. Normal daily stress like running two business, I do powerlifting twice a week, I volunteer a lot with my church so I’m doing stuff with them twice a week, I have a long distance engagement which is great but it’s also very difficult to have that be the situation.

Kelsey: Mm hmm.

Laura: All that stuff is stress and ultimately I don’t think it was leaving my body a lot of metabolic reserve to handle the fast so I think adding the fast in that situation made it worse. That’s a season of my life that hopefully will not be the rest of my life being that level of stress. Maybe next year I’m going to be less stressed and I can try it again. Or maybe next year I’ll do more of this traditional 8 hour feeding window fast where I think my body handles that better.

Kelsey: Right.

Laura: Ultimately I don’t want people to feel like they have to fast for good health. You don’t have to, it’s not like you’re going to die 10 years early if you don’t fast. Ultimately if it causes you to feel like crap when you’re fasting, then that’s not a good thing either. Honestly I like to prioritize quality of life over longevity because nobody wants to live a really long terrible life.

Kelsey: Mm hmm.

Laura: I would think not. Maybe there’s some people out there that do. But if you feel like garbage when you’re doing it and you feel better when you’re not, then I’d say regardless of what the potential long term benefits are that it’s not a good idea.

You need to think about why you’re fasting and why this time of your life either is or isn’t a good time to do fasting. Also you need to pay attention to the strategy that you’re taking and make sure that okay I am eating enough when I’m eating, and I’m not doing a type of fast that makes me feel terrible. So just keeping all this stuff in mind and remembering that you don’t have to. It’s really not that big of a deal. I think a lot of people in the Paleo community kind of say that, no, this is something that you have to do and it’s bad to not. But I don’t agree with that.

Kelsey: Yeah.

Laura: I think use it if it works, it helps. But if not, it’s not the end of the world if it doesn’t.

Kelsey: Boom. Done.

Laura: I would do a mic drop, but my mic is suspended so it’s just going to be imaging that.

Kelsey: Yeah.

Laura: Yeah, that was a long episode. I feel like we had a lot to talk about. It’s a big topic.

Kelsey: It is.

Laura: I’m not surprised we could talk a long time about it. But if you guys have more questions about fasting, please let us know. You can go to TheAncestralRDs.com and click the little stripey tab thing at the top right corner of the screen and that will open the contact tab, and that way you can submit your questions either about fasting or about anything you want us to talk about. We’ll hopefully answer it on the next show.

We’ll also love to hear your suggestion for interviews. We have a couple of interviews that we’ve recorded. I know Noelle’s was published last week. Hopefully you enjoyed that one. I know I did. Then we have one next week with Ben Greenfield. But we really want to get some more interesting guests on the show. If you have someone you want us to talk to, please let us know because we’ll definitely reach out to them and just get a lot of different voices on the podcast.

Kelsey: Yeah.

Laura: Thank you for joining us everybody. We will be back here next week with our interview with Ben. We hope you have a great rest of your week.

Kelsey: Alright. Take care, Laura.

Laura: You too, Kelsey.

+ show Comments

- Hide Comments

add a comment

Leave a Reply

Your email address will not be published. Required fields are marked *

Your Friend and Business Mentor

I'm a women's health expert and a registered dietitian (RD) with a passion for helping goal-oriented people fuel their purpose.

I help nutrition entrepreneurs grow their income and their impact by packaging their brilliance into transformative coaching and consulting programs, and get crystal clear on their marketing strategy.

I'm on a mission to help nutrition business owners drop the hustle and come into alignment with their ideal business goals, so they can work from a sense of ease and abundance, and build the online business of their dreams. 

Let's get to work!

Hi, I'm Laura.

meet your mentor

Grab this!

50+ Tech Tools To Help You Run Your Online Nutrition Business

Not sure what tech to use to get your business off the ground? Still trying to ducktape your business together after months (or years) of running it?

Get my list of the best free and paid tech tools to help you run your online nutrition business smoothly and efficiently, so you can focus on what you really love to do... helping your clients get healthier!

First Name

Email Address


Get the clarity and confidence you need to turn your expertise and passion for coaching into a wildly successful online business.


© 2023 Laura Schoenfeld Coaching
All rights reserved. | Terms and Conditions 

Meet me on the 'Gram