S1E3: Intermittent Fasting 101 w/ Sarah McPherson | Strong Bodies by Tish Podcast

Tish (00:00):

Welcome to strong bodies by the Tish podcast. I am so excited that I finally have this podcast and this platform to share my experiences with you. 30 years of experience. I love to talk. I love to share my stories through this podcast. I hope you get inspired, motivated to live a happier, healthier life. Please enjoy this podcast is sponsored by strong bodies by Tish. You can find out more about my program on my website, train with tish.com, or you can check out the link below and try my seven days of training for free will. You'll get a better idea of my style, my concepts, and the way I love to train my clients. All right. Hi Sarah. Hey Tish. Thank you. Yeah, so good to see you. I miss your face. I used to see you so much and I mean, I see you now in the app with your completed workouts, et cetera, but to see your actual face is so nice.

Tish (01:05):

I do really miss it. I actually miss people more than I thought I would be now in Colona. So thank you so much for joining in on this podcast is going to be probably out of the episodes that I've committed to. We'll probably do more after this 10, but I have to say that this one probably is going to be no pressure. The most-watched one because I've talked to a lot of women as women, but mostly women about the whole fasting thing. So this is why I wanted to have you on you're the expert. Sarah and I have known each other for quite some time. But I wanted to quickly first before I get into a sort of how we know each other and how we got into talking about fasting. I wanted to ask you first it might be just my imagination, but fasting seems to be something that is very popular or growing more people want to know about it. I know a lot of my clients are asking me a lot more about it. So is that something that I'm just paying more attention to and learning, or do you think actually the fasting culture is becoming more popular?

Sarah (02:19):

I think it's becoming more popular. Definitely, when I first started hearing about it was mainly in the context of people who have the disease already like diabetes in the obesity research. And then it's absolutely, I think being brought into the mainstream because of all the benefits that it's showing with respect to aging inflammation and you know, in the biohacking community really realizing it's its benefit. So I think that people are starting to realize like as a way to promote health, especially with the pandemic and looking at how we wanted to potentially take control of our aging, that, that has really brought fasting and a fasting lifestyle more to the forefront for people.

Tish (03:05):

Yeah, absolutely. I just when you say those things, it's just music to my ears because as you know, when we first met several years ago we both were like, yeah, we're now in our mid-forties and I really want to make sure that I, and you, and this is why I was so excited about training you was that you were like, I want to make sure that I have the ability to do the things that I did in my thirties and early forties. I still want it like, cause you're a very big outdoors person. You hike, your mountain bike, you're way more extreme actually than I am. And so that was why I really welcomed an opportunity to train you because you were like, I want to make sure that my body stays young. I think that back then so just a little bit of information, Sarah. You are, an ER doctor at the foothills and the

Sarah (04:01):

Children's hospital.

Tish (04:03):

Children's that's right. Children's in Calgary. And how long have you been there?

Sarah (04:10):

So I finished my residency training in 2004. And then I started at the children's I think it was 2006. So it's been, my entire adult life has been working in healthcare and I think especially working in the emergency department, I see the end-stage of the disease every day. I see people aging and how just a simple injury can take away your independence. And so for me, that was the major thing that has motivated me to look into what can I be doing now in my forties that will help me have the best life possible when I am in my seventies, eighties, maybe even nineties. And that's why for me, it was so exciting when I got to meet you because that aligns with what your philosophy is in training. And, the first step for me in my whole wellness journey that I've now been on the last three years actually started with you and the benefits of resistance training and how, you know, you have to, to keep doing that once you get into your forties to maintain your muscle mass. And then that helped me actually learn about so many other things that now, it's come full circle and I get to be on your podcast.

Tish (05:24):

I know it's a ma and honestly, I cannot thank you enough. So yeah, that basically was that what three or four years ago that we started training that

Sarah (05:33):

Was 2018. Okay.

Tish (05:35):

So about three and a half years ago. Yeah. And so basically just to quickly go through your story a little bit you know, you wanted to get back into it, you always were into fitness, and you did know, you knew that the strength training component was missing. So we got into it and you, you also had, and I'm going to also allow you to share your story. I don't need to tell your story for you, but I wanted to first before we get into the whole fasting thing, I wanted you to share a little bit about what you were doing before you got more educated and through your, through your certification, which I will obviously want to know more about as well. But what were you doing before you become more knowledgeable and more in tune with the fasting? What was your lifestyle like in terms of eating before you started and how, yeah? And, and then maybe slowly or, or just small ad what got you thinking about, you know, adding the fascinating into your lifestyle?

Sarah (06:40):

Right? So for me, I would say the whole journey started back in 2017 when I was like a lot of people in their forties women, I think, especially I was so caught up in work. I had just gotten on such a treadmill that I had let a lot of my healthy habits go. And it literally was only 11 months of not exercising consistently and not being kind of mindful of what I was eating and taking time with friends and doing the things that I know are healthy for me to go from being thriving to being in constant pain. Like all of my soft tissues were starting to ache like burning. I was having abdominal pain. I was getting episodes of where I have this terrible busyness called vertigo. That was starting to significantly impact my life. I had depression. I was burnt out from work.

Sarah (07:38):

Like, I came to you literally Tish at like rock bottom. I was at a point that I had to resign from part of my job that I really had a passion for and love just cause I was like, I don't know what else I can do. Like I'm now starting to see all the things I see in my patients. They come into me with all these symptoms before your disease starts and I'm like, this has got to stop. So I realized that having a trainer was like a Keystone habit for me. And it really is like your app. That is what helps keep me in the lane of health. And so you were like the start of the journey. And then one of my other very close friends, who's had some chronic health issues started working in a functional medicine clinic.

Sarah (08:25):

And I was like, this is really interesting. Like what's this and that led me into looking at functional medicine, which is basically looking at what are the things that are actually stressing your body, like what's causing the dysfunction and what can you do to take away the things that are like depleting factors and what can you do to add in what are the healthy things that your body needs to function properly? So this led to a lot of experimenting. And if you look at it like biohackers, that's what it is. You like to experiment with yourself. And so as you'll probably remember, one of the first things I did was getting rid of gluten. I had to get rid of certain foods that clearly were causing me problems with inflammation. But even with doing that, which was like cutting out pretty much all gluten, I cut out most sugar.

Sarah (09:13):

I had cut out nightshade vegetables and a lot of lectins. I was definitely a lot better. I definitely was, was not having much in the way of weight loss. I was pretty fine, but I have a tendency to carry weight around in my mid-section for sure. And so finally through my training in functional medicine, I finally took the course on energy. And that was the defining moment in my life is when I basically woke up to the fact that basically, your mitochondria are like yourselves energy plant your energy source. And when they stop working, your body stops working, like you've lost your power source. And so that is what finally was like, I'm willing to do it. And so I went cold Turkey on to like a six-hour feeding window. And that honestly was like the turning point for me.

Sarah (10:16):

I could not believe how much better I was with that type of eating pattern to the fact like probably four months in, I was having multiple people. Like, what are you like, what have you done differently? Like, you look like you're aging backward. So I like was like, I'm reverse aging. But actually, now that I've looked into it, I'm like, actually I actually probably have been reversed aging. And then over the summer, I have to admit it's good that I'm on this podcast, but like I kind of loosened up a little bit and I'm like, oh right. I will go right back to where I was. Not to the same extent, but I'm like. When I stop eating this way, I start having pain again, I start having less energy. I can notice now such a big difference, which is great because now I have this, I can reverse my trajectory a lot faster. I can change my trajectory a lot faster and kind of course correct way better than I used to be able to. But yeah, I would say for me like my version of fasting, which is a restricting window of eating has been really beneficial, as a game-changer for me.

Tish (11:34):

I mean like Sarah, and this is why I opened my mind to it because I have to be honest. And I spoke about this in my initial episode or my first episode on how my own experiences watching you go through, it was a light bulb moment for me. I was like, you know what? I have to learn more about this because I watched you change right in front of me. I remember. So clearly we were training outside of the park a couple of summers ago. And you were talking about it and you were taught like really scientifically, like what's happening. We're going to talk a little bit about what actually is happening when you do the fasting inside because at the cellular level is like the big, game-changing information. And that's what I really wanted to have you on here for.

Tish (12:32):

And I will be honest when I first trained when you were talking about it, I was interested, but I also was not a big believer in fasting. I always was like, it's just a way to restrict calories. It's calories in versus calories out. If you want to lose weight, just stop eating so much. You know, why do we have to be so dramatic? And that's always been my thing. It's like, let's just keep these simple diets don't work. I was kind of still in that mindset. And then a couple of months went by and your energy was better. Your knee issues. When we were squatting, went away, you were moving your body, and clients would be coming into the studio and going, Sarah, like you were absolutely transforming yourself. And it was just something that I was completely causing at this point I had been training you now for a couple of years.

Tish (13:25):

And although we were, you were getting stronger. And of course, there were some changes. You know, you just got to the point where like, I'm ready to take it to the next level, which just organically happens. We just start and then we just keep going as we commit to the process. And so for you to go from there to there so quickly, like really, and just the biggest thing for me was just your energy was like, you were always so easy to train, but the ability for you to move your body and you just seemed happy. You seemed so happy. And then, just quickly before we get more into you just over at the beginning of the summer, I went through a very stressful period. And my eating completely changed, not on purpose, but because I was so stressed, I had no appetite.

Tish (14:16):

And I found myself literally having to force myself to eat once, once a day, because during the day I just could, it was just the anxiety of, and some women or men eat when they're stressed, I'm the opposite. And that was happening to me. And then before, it, same thing with me. I, even though I was going through such a crazy stressful time I felt pretty happy and I felt pretty in control and I was sleeping better. Not at the beginning, but once I started, really changing and I wasn't doing on purpose, but I woke up one day and I looked at myself, I went, wow. I have definitely leaned out, but my skin looked better. I had more energy was speaking more clearly my mind fog, all of that was gone. And I thought, this, I feel like I'm, this is fasting.

Tish (15:10):

And so I became more aware and more mindful of it. And then I realized that that's in fact what I was doing. And because I started doing it when I was going through a stressful time, my body just got comfortable with it because I do think, and this isn't one thing I want to ask us a lot of times fasting and keeping in a window of like the 16 and eight or the 18 and six, whatever you're doing 18 and six hours. Is that what it is? That there's like this period where the hunger is just out of control. I never ever felt that, but from the reading that in research that I have done in you, I would obviously love for you to make sure that I'm speaking clearly and correctly about this, but your body adapts and adjust to the changes. So if you can get through, and I always said this to a couple of my clients that I'm coaching right now, one-on-one is your body adjusts, give it a couple of weeks. And would you say that that's true if you can really stick with it, your body, the hunger, all of that goes away, right?

Sarah (16:21):

Absolutely. I kind of think of it like adopting a fasting lifestyle is very similar to what all of your clients are doing when they're adopting a weight training lifestyle. When you first start, you don't put two plates on the barbell and try and squat it, right? Like you have to work up to the ultimate, you know, you keep challenging yourself more and more, and as your body adapts and becomes stronger and more nimble and how it is able to deal with the stressors it's facing, then you can do more. So I think that's a big thing with a fasting lifestyle. It's not like an all-or-nothing thing, right. It's not like, oh, you have to go like on your six-hour feeding window or all is lost. No, like if you're staring into it, maybe start slowly, like, just start shaving off an hour every morning, where you push back when you start eating until you maybe reach your goal of getting all of your calories that you're eating for the day in over a six-hour period.

Sarah (17:16):

And then the other thing is I think having this all or nothing thinking is really limiting for people, because then if you have someday where maybe you ate for eight hours, you're like, oh, I failed. No, that's okay. Like, sure. You just, well fine. You, you still are eating like eight hours instead of like 14 from before. But it's about making a part of your lifestyle and giving yourself the permission to, to say that, you know, you're taking steps to where you want to get to and you don't have to get there immediately.

Tish (17:48):

And so you say that, sorry, go ahead. I don't want to go for it. So would you say that, and this is, this was the biggest thing that I had, sorry, this is not a question that I sent you, but I know you'll be able to answer it. There are different methods of fasting. And so the way that I kind of address it with some of my clients, not everyone, but some of my clients. And I find it's the one it's the clients that I kind of say like, they have done, they're doing everything they possibly can. They're getting in their lifts, they're getting in their steps, they're drinking their water. There's just that, there are just a couple of things that they're just not quite happy with. And usually, its body composition changes. Right. You know, they're feeling like they've plateaued. And so when you

Sarah (18:41):

Say that there's like stepping stones, just like there is with lifting weights. Is there a way that you now, you know, maybe you can touch upon the different methods of fasting? I know that there's like some days during the seven day period where there are two days where you eat 500 calories and then you have a refill day, can you mix and match the different methods and you, can you play in and work individually with each person and still feel like you're getting to more of a cellular level change in your body, or does it really have to be that really consistent 18 and six? Or can you be a little bit, transitional throughout the week or like how effective, how strict you have to be to, for it to really be making changes at the cellular level. Like what do you need to do to get there?

Sarah (19:34):

Yeah. So number one, I don't know that anybody knows for sure. Because some of this is very new. And even like, what is the optimal fasting strategy for an average healthy person? I don't think we actually know that yet because so many of these are actually being studied on people with diseases. And then they're doing studies looking at the cellular level on animals and extrapolating into humans. So I think that the best thing to do is to try it and see what works the best in your life, because that's what you're going to be able to continue doing in general, though. You need to have a 14 hour fasting period, to get some of the cellular benefits. Now, do you have to do that? Every single day probably would be best if you can, but if you can't, then you're still getting some benefit by doing it.

Sarah (20:30):

Sometimes having said that your body gets used to things it's resilient, it changes based on what it's being forced to do. So to change your body, to be metabolizing fats as its fuel source, which is much more efficient, it has to be put into a scenario where it does not have access to carbs because insulin will Trump everything. So if you've got insulin surround, like go coursing through your body and it will be released every time you have sugar around that it needs to deal with, then you're not allowing your body the opportunity to switch the metabolic pathways to become an efficient fat burner. And that's what I've noticed for myself is that when I'm consistent with my time-restricted window, then after about three weeks of being very consistent, then I'm getting the benefits of the energy and the clarity of thought and the mood.

Sarah (21:35):

And that's because I've switched to using fat as fuel. And one of the ketones beta-hydroxybutyrate is one of the main substrates or one of the main fuel sources that the brain likes to use. So I think it's best if you can do it consistently, that's what your ultimate goal should be. But if you can't get there like it, it's stepping stones, like pull yourself together, figure out what was it that led you to not be as successful as you'd like to be. What can you learn from that? So that you're more successful next time. So I would recommend for most people to do a time-restricted eating window, and then from there, you can play around like doing so there's like the five. Do you want to talk about the different types of fasting strategies? Okay. So people talk about intermittent fasting and they lump it's all lumped together.

Sarah (22:27):

It's right. So you really have to tease out what people are talking about. I think it's better to just refer to it as a fasting lifestyle, which kind of can encompass all the different things. So there's the restricted eating window. So the timed eating, that's where people talk about the kind of six and 18 or the eight and 16, where you're basically giving yourself these prolonged periods of time, where your body is not getting calories in. And that is the benefit from it is that you're having prolonged periods of time where your body's not being exposed to insulin. And number two, when, when cells are not getting active energy coming in, it's kind of like their repair time. I kind of think of it like when people who are shopping, if you are constantly shopping and buying new clothes for your closet, and you don't take time to take the stuff out of your closet, you're just going to end up with an overflow.

Sarah (23:21):

Like it's going to be this disastrous mess. So that's the same with the body. It's great, so there are times you should be shopping and bringing stuff into your body. It needs much more time if you've ever done it, it takes way more time to organize your closet and get rid of stuff than it does to go out, shop for two hours, and bring a ton in. So you need a much longer time for the repair and reorganization and, and for your body to move into that cellular clean-out phase. Right? And then in addition to that, people talk about like the five and two. So that typically is for five days you're eating as you normally would, which oftentimes should be yeah. Still a restricted eating window. And then for two days of the week, you either have a restricted calorie. So kind of going down to five to 600 calories for that entire day while you're eating or for some people it's a complete fast of all calories.

Sarah (24:14):

So when people are talking about the five and two,, it actually can be either of those things, you kind of need to tease out, like, what are you talking about here? Then you'll probably also have heard of fast mimicking diets. So that is where it's kind of like a five and two with certain days where you're basically giving yourself restricted calories. And oftentimes they're, they're talking about in restricted carbohydrates, especially. And then you've probably also heard about carb cycling. That's similar to a fast mimicking diet in that you're going for certain days where you're on ketosis and then other days where you're not restricting your carbohydrates as much. And essentially you're basically doing the same thing. You're restricting the amount of energy source that your body has in the way of sugar. So that you're forcing it to use fat.

Sarah (25:05):

And you're basically also giving yourselves a period of time where it's like, we're in a cleanup mode right now. So it switches to different inflammatory. So genes get turned on which affects how your inflammatory system works. It can affect the Tullamore telomerase concentrations. We'll talk about that more. It can affect your stem cell production. So a lot of things that are going on when the body's in that repair mode, and then a lot of people that you may have also heard of autophagy. So that's also the period of time where your body's like clearing out the dead stuff or the stuff that's not working, the damaged stuff. And so the studies that looked at autophagy is you have to be in a fasting period for at least 17 to 24 hours. Some people say 24, but it actually was 17 to 24.

Sarah (25:57):

And then in addition to that, if you are eating, they were restricted to less than 20 grams of protein. So then either a complete protein during that while they were on this study looking at a top McGee. So there's a lot of different things out there. But I think if most people if you just try shortening the amount, like the time window, when you're eating, that's probably the best place to start. And then once you're good at that, you can go into maybe like putting in a full 24 hour fast. There are some people that will go into these prolonged fasts where you can go for like three to five days of not eating anything. And that apparently has some very beneficial effects on inflammation and on healing as well. So like I was reading one physician who has a patient that as soon as they start feeling sick in any way they stop or has like an ache and pain, they stop eating for like three to five days. And then like, they, they get better and then they’ll start eating again.

Tish (27:01):

I never tried that. And, but my only concern about some of this is how do you have self-discipline? Like how do you not go? Because I mean, from my experiences, if I've gone too long without eating, or when I competed in bodybuilding, I went five months with very restrictive calories, very restricted types of foods. And it was extremely difficult for me to stay disciplined once I was given the freedom to eat. So do you have any suggestions on what you can do to make sure that you're not just doing these fasting periods days, hours, and then not just completely, like, would you ruin it if you just started eating like a crazy person or chose foods that were not healthy? And it's like, I don't want people to be fasting and doing all this good for your body and then sitting down and, or pulling into a fast-food restaurant and eating the fries, the burger, the fast-food junk to me that would be not beneficial. Maybe it is what, what is it beneficial to eat? Like, can you eat whatever you want?

Sarah (28:18):

So, I mean, I think you can eat whatever you want, but you won't be getting the best. You'll have the body that ate whatever wanted to, you know what I mean? Like, that's the other thing that was a real switch for me is my body is made up of what goes into it, right? So if I want to have a body that is functioning optimally, I have to give it what it needs to be able to function optimally. So one of the things I can give it is a prolonged period of time, where it's allowed to repair and heal and replenish itself, and that's the fasting windows, but then when I'm eating, I think you have to be very intentional about what you eat, right? Because in that time, when you're eating, you have to make sure you're getting all of the nutrients that your body needs for the building blocks. And if you're not doing that, you're not going to your body, won't be able to do the building.

Tish (29:12):

Right. So, yeah,

Sarah (29:13):

That makes sense. So I think, you're probably will be getting some benefit from the fasting, but you, you might be getting actually some damage because your body is being so stressed by what you're putting into it in food. And now it's having to deal with another stressor that actually can lead to increase cortisol, increasing in a worsening of inflammation. It's kind of like finding this balance. Your body wants some stress, but not too much. So I think, it's just like weight training. Like you want to add resistance so that it's difficult, but if you put too much difficulty on you get injured. And so I would say it's the exact same thing you're putting on this extra stressor on your body of fasting, which can be very beneficial and positive for you. But if you're doing that while eating all this crap, or also having a super stressful lifestyle outside of it, your body won't be able to handle it.

Sarah (30:06):

Like it was when I first started this in the first week. So again, I wasn't adjusted. So, and I also did, wasn't really paying attention. So I was not starting to eat until noon. And I decided to go out and climb the east end of Rundle, which if anybody's done that it's like up like straight up the mountain kind of hike and it was supposed to be super hot. So we decided to start this hike at like eight in the morning. Well, like within two hours, I was, I have never been so depleted in my life. I'm like, I would Mike, my stress like that. I was putting on my body. It was huge. So I was like, no, that's too much. Like you can't be fasting yourself and putting yourself through a massive exercise. And then if you add onto that eating crap like it's just, that will overwhelm your body's capacity.

Sarah (30:55):

So right. In order to be fasting in those windows that you have to eat, you have to make the most of it that you're putting in the good stuff. And then, you know, when your body's functioning so well, if you have, you know, once a week or once every couple of weeks, whatever that you're out with people, and you want to increase the amount of time that you're eating because you're out for dinner, you want to maybe eat something that is not as helpful for your body's function as, as it could be. Well, that it can adapt to just fine. It's what's happening to it every single day. That is what's going to make a big difference.

Tish (31:32):

Yes. It's kind of like the 80 20 rule, right? If 80% of the time you're doing your fasting, you're putting fuel in your body. When you are in the window of eating, that's going to nourish your body. Love how you described that, Sarah. And then 20%, maybe Saturday night and a little bit of Sunday is sort of what I say. You know, just so people don't feel like they're, you know, completely, you know, on this specific cause like for me, it has to be a lifestyle, right? And this is the very first thing that I say to people is if this is something you cannot do for the rest of your life, then you need to make sure that you're adjusting. So you can, because you'll get success. If you do all of the things, any diet works, the problem is it needs to be incorporated in life.

Tish (32:22):

And so that's why I always do check-ins with my clients. Like, how are you feeling? Are you feeling deprived or is this making you grumpy? And when they say I actually feel incredible. And I think that is the thing. This is the kicker. Once you start getting, once you get there, once you go through the couple, a couple of weeks or however long it takes for your body to adjust and you start feeling the differences, start seeing the differences. You're like, okay. It is so worth all the effort. And I would have to say that that's my biggest thing I would want to share with people is that you do have to make sacrifices and some harder decisions, but once you start really getting the benefits of it, it's, it's what motivates you to keep going, right? Don't you think? And that's the whole thing, right?

Sarah (33:13):

And then like for me, the way that I think about it because I also sometimes viewed a lifestyle change as an intervention, kind of like, like medical intervention, you do it and it fixes you. No. It, if it will fix you for a time, but then as soon as you go back, to bring in those factors that are depleting, you, you will become depleted again. So it's you can't, it's not a one-time thing. That's what, that's why it is a lifestyle. It has to be, if you want your body to function, well, you have to be taking away the things that are injuring it and you have to be giving it the things that are nourishing it. If you do that, your body will function as optimally, as you can make it with the body that you have. As soon as you start going back again, it won't function again.

Sarah (34:04):

And that's definitely, that's something I've had to learn because I had to change the way I think. I now can very clearly see it when I go back to not doing the things that I know my body needs to be healthy. Then I go back to feeling exactly the same as I did before. But now, fortunately, I know what I need to do to be healthy and I can feel it. And that has been, as you say, that has been one of the major motivators is now when I go off track, I can immediately start feeling different and then I can course-correct faster versus before. I just probably felt bad all the time. So you don't really notice when you're starting to feel bad again. Cause you're just baseline is bad.

Tish (34:40):

Yes. Exactly. And so, I don't want to take up too much more of your time, but Sarah couldn't, do you mind because you do have your education, do you mind just sort of telling us what's going on, you know, not too detailed, but give us sort of a view on an image. And I know you used, you would say this to me or explain this to me when we what we're training and it was, I was like, can you need to like write that down for me? Cause there's no way, but so I just wanted to, you know, quickly have you explain what's happening at that cellular level. And because I think sometimes people automatically assume that fasting what you know, and this is again, has changed so much. And this is what I was speaking about a bit about in the first episode about how I have changed so much.

Tish (35:31):

I can't even believe that I am sitting here talking to you about fasting because you know, even five years ago, I just never would have opened my mind to it. So and now I want to just learn all the information. I want to know all the stuff. And I'm sure that most of the people who are listening today would also like to know sort of what exactly is happening. Because for the first 15 years of my career, we were saying, don't go hungry, eat breakfast, it's the most. And so if we can now say that this is okay for us to do maybe in a quick little way, describe what's happening inside of our bodies. That makes it so beneficial.

Sarah (36:13):

So yeah, there's a lot of stuff going on. I'll try and break it down into kind of the key components, but for me, another very helpful way to think about it is that our bodies had to adapt to figure out how to make sure how to make starvation something that's essential for a start for survival because that's what our ancestors had to do. And so we are adapted. We have bodies that actually need to have some episodes of starvation to function properly. Like that's why fat is actually a magnificent thing that our body can do. If humans could not make fat, we would have all died. It's just now we would have died off. We need fat because it's a very efficient, fuel source, especially when you don't have a constant supply of calories around. It's just the, now we have a constant supply of calories around.

Sarah (37:04):

And so now we see fat as an, as a bad thing, but actually fat is a very amazing thing that our body has the ability to do. So basically what is happening, let's talk first about energy. So your body in order to have energy has to take in the nutrients that you have. And it has to basically turn it into a fuel called ATP. So there's kind of two ways to do that. One is with glucose. So everything in a carb gets broken down into glucose then it can be made into fat as a way to store it. And then there are also proteins that can be used as building blocks. But some of it's also turned into glucose if you want energy. So you have to have essentially glucose that goes through a Krebs cycle and then they move into something called your electron transport chain, which is where you really get the major production of energy.

Sarah (38:00):

And that's all happening in a little thing inside your cells called the mitochondria right now, the thing is, is that when you take glucose and run it through the amount of ATP you get is like around 30 for one molecule of glucose. If you take the same glucose from a fat source and it comes in as like two units break it apart by the time that one's finished, you're getting like 80 to 90 ATPs from it. So you're getting way more energy being made when you use fat as the way to get into this cycle, as opposed to when you use sugar.

Sarah (38:35):

So one thing is if your body is constantly okay when the mitochondria are working if there's any insulin around, you were preferentially using sugar, it's just insulin is like the big guy, okay. If it's there, sugar is being used. And when you do that, you can imagine these little power plants in yourself having to work. They're like they're working so hard because they're trying to make so much energy. They've got a constant barrage of glucose coming in that they have to transform into an, as a fuel that we can use. And when they do that, number one, they kind of run out of steam. So in order to do it, they have to do something called fission. So they break up into these little small power plants because they're trying to keep up production. Well, those little power plants don't work very well.

Sarah (39:33):

Not as well as when they're all together, but that's what they have to do. So you're going to end up with mitochondria that are not as efficient when it's constantly having to work. The other thing that happens, which if you imagine a power plant, when you're making the energy there are fumes that are made, so there's the combustion effect. So when the mitochondria are working to make us energy, it gives off things called free radicals and other toxins, which are normal. But when they're working all the time, they're constantly releasing these chemicals that are damaging. So you're not only working these poor guys to death. They're not going to be able to work as efficiently. So that's why you don't have as much energy feeling as your body. Like, you're just like, I have no energy. I'm so tired. That's your poor little mitochondria are having a hard time working.

Sarah (40:23):

And then they have this toxic fume that they're releasing. So that's called the oxidative stress that they're creating. So if you give the body prolonged periods where those poor little mitochondria are not having to work as hard, it lets them fuse back together. So they become more efficient and you also are not making as much oxidative stress. Like you don't have as many toxic fumes kind of like pollution in your cellular pathways. So it's and all that toxic fume causes damage. It causes inflammation. That is what leads to disease. So that's one thing going on. The second thing that's going on is when you give yourself prolonged periods of time, where you're not eating your insulin levels can go down. And a lot of us, me included because of how we've had the opportunity to eat, which is high calorie, oftentimes high sugar diets.

Sarah (41:17):

A lot of us, by the time we reach middle age, are developing insulin resistance. Insulin resistance is the precursor to diabetes and many, many other bad things. But your body also is this amazing machine that is resilient. So when you give it long periods of time where it's not around insulin all the time, then your receptors can become more sensitive again. So you can actually dial back your insulin resistance. And then you that's one of the reasons why one, you start losing weight is that insulin stores fat. Well, now you don't have insulin around as much. Plus your mitochondria are learning how to use fat as fuel. So you start burning fat. So that's kind of one of the byproducts that your body is starting to function a bit better. And then insulin resistance also causes inflammation and then inflammation causes and causes insulin resistance.

Sarah (42:11):

So you can get in this terrible cycle that can be difficult to get out of so fast and can help with your insulin resistance, which then helps decrease the inflammation in your body. And then that decreases your health risk of pretty much everything else. Then at the same time. So that's, what's happening with your mitochondria that's what's happening with insulin. Then in addition to that when your body is going through a period of starvation, it actually turns on certain genes in the cells that help upregulate your immune system, where it decreases your inflammatory cells. And upregulates the part of your immune system called your T regulatory cells. So it's like your healing function. So you can decrease the bad inflammation of your immune system and increase your healing aspect of the immune system by it. Then it also has been shown to improve your neuron’s ability to grow.

Sarah (43:12):

So when people that have the neurodegenerative disease, or if we're thinking about the risk of potential dementia, there's probably a big benefit to be had of these periods of decreasing your caloric intake because of how your neurons are also being affected by it. So they actually have been showing, have shown that, these neurons actually are growing and regenerate when they're in this kind of situation. And then there's also when you're in a period where you've reduced calories, it stimulates your stem cell production and stem cells, how to have a lot of an enzyme called telomerase, and that helps repair your Tila MERS. And the T lemurs are like the protective caps on the ends of your DNA, kind of like the plastic on the end of shoelaces. So they don't unravel. That is what Tealium your team members are doing. And so as your telomeres shorten with age. So as you're able to get more of the enzymes that protect those telomeres, that also is probably one of the reasons that fasting seems to help with aging. Wow. So, so many things are going on. I mean knows how many more things, right? It's such a crazy shift in

Tish (44:31):

The way. So many of the trainers and professionals in this industry have, it's, I was just talking to another coach a few weeks ago and we're just dumbfounded that we're now pushing, going periods with feeling hungry. I mean, it's just, but to hear how many health benefits it is such a huge, it's exciting for people. I think people will listen to this and go holy. Like I could really make some huge differences in the way I feel in the way I move and the way I look just by changing how I'm eating and the timeframes on which I'm eating. And so I just, it's amazing. It's super exciting. The only other question I quickly have for you is because I don't want to go take too much more of your time, but the one thing I wanted to ask is are there certain types of people that should not fast, like pregnant? Should you, you know if you're pregnant, should you, or you know, are people, going through menopause, is this something that would be beneficial? Is there anyone that should be avoiding it or is everyone would benefit, from this?

Sarah (45:46):

So I think that there are probably some individuals who should avoid it or if they do it should be supervised because they're they have either diseases that, so their body's not functioning. Normally it actually has injured. Their body is injured and it now actually has a full-on disease. So if you have insulin-dependent diabetes they're going to be much more difficult to regulate because they're metabolically more complicated than we are. People who have recurring hypoglycemia for, certain reasons, would be potentially too fragile to just jump into fasting without a certain sort of supervision. Some people are just very metabolically inflexible. And if you jumped into doing something too radical, too fast, they could have difficulties. And you'll know that that's you if when you start fasting, you feel horrific. That means to pull back. Like you need to do it more slowly.

Sarah (46:47):

Okay. If you're pregnant, if you are somebody who suffered from an eating disorder, the way that they kind of view food and eating is, is made, be different than everybody else's. So they might need to be more careful. And then also if you're already frail and very underweight, you need to be careful because then you're like, why are you so underweight? Are you actually getting adequate nutrition? So you have to make sure you're getting adequate nutrition in addition to fasting. And then yeah, you asked specifically about menopause. So I was doing some, doing some reading to see if I could sort that out because there does seem to be a lot of questions around menopause, and what I was able to find, which makes sense to me is that again, it comes down to the stress aspect. So there's kind of like the hierarchy of hormones.

Sarah (47:40):

So oxytocin is the top. We don't, it's the one that makes you feel happy. Next is cortisol. Cortisol is like your stress hormone, right? Next is insulin. And then after that are your sex hormones and they all interact with each other, but they're actually made through very similar pathways. So, not insulin, but like cortisol and your sex, sex steroids are made through the exact same pathways. So if you're somebody who's under a ton of stress, your body will preferentially make cortisol and it might leave you depleted in your other hormones like testosterone, progesterone, estrogen. So if you're doing fasting, you have to be careful that you're not putting undue stress on your body. So if you're someone who's like stress levels up to here and you add another stressor and you're going through menopause, where already you're dealing with fluctuations of, of sex hormones, you might end up running into more problems.

Sarah (48:43):

Oh God, what you should do is have a slower approach to fasting because that actually can also help with your other hormones, like insulin, etc. And then also be actively looking at ways that you can reduce other stressors in your life. Like you probably shouldn't be, maybe your body can handle this, but you might not be able to tolerate ultra marathon running and working 80 hour weeks and feeling like you have to be a superwoman and only eating in six hours a day. Like that might just put you over the edge. So you have to really be paying attention to what your body's telling you.

Tish (49:22):

Right? Exactly. So I guess it's okay to fast when you're in menopause because I have had some people go, well, I heard it was bad. So what I'm hearing from you is some, yes, it may not be great, but your body will tell you if you need to push back or pull back a little bit and go a little bit slower and you need to be in tune to your body. So I think that's sort of what you would say, right? It's not a bad thing. It could help you, but it also could make things harder for you if there are other stresses in your life that are just not being managed properly.

Sarah (49:59):

That's right though. I would still say, even if you're in that situation to slowly adapt into a time-restricted fasting lifestyle and then also work on really being mindful of what you're eating. So making sure that you're eating like a big variety of vegetables, especially some people call it like a keto bio, bio keto biotic diet, where you're like lower in high in vegetables, high in things that are helping out your microbiome. And then also looking at what do I need to do to help decrease my life stressors. And you know, there are tons of different things you can do there. Right. And each person's going to be different as to what would be most useful for them to do.

Tish (50:49):

Okay. Well, that's amazing. Sarah, feel like I might have to have you back on for another episode because I think we just sort of touched on things. But I have to say I've learned so much, and I know that the people listening will really have our confidence in doing things. I think we need someone that's someone like you to say, not me, someone like you, who's an actual doctor who has the education and the certification behind it saying, yes, this is healthy. This is safe. It's, it's manageable. Because I really, it was super important for me to not just write notes on, listen to you and write notes. It's come on here, have you as the expert to come on here and say, these are all things that are happening in your body. And yes, it is.

Tish (51:37):

As long as, you know, you've got other things managed properly. And so I just, I, but I do feel like we probably could talk for another hour and another time. So I might have to talk to you about that, but I'll space it out. But is there anything else that you quickly wanted to add? If I didn't, if I missed anything we have like a couple more minutes., other than that I'd love to just maybe keep in touch in and have you on, in a couple, maybe a couple of months or something.

Sarah (52:09):

Sure. I would love that. But I would say just with respect to fasting is one, give it a try, try it for at least a month. Okay. give yourself grace, if you fall off the wagon, you can just get back on again. And then also recognizing it's one tool, right? It's one thing that can be very healthy. And it's, you know, sometimes the combination of things is what you may need, but there's, I know of a lot of people who have been that this has been the game-changer for them. So it's definitely, I think it's worthwhile so long as you're not one of those, people that are more fragile for whatever reason. As far as how your physiology works, you know, it's worthwhile to just give it a go.

Tish (52:55):

I love that. Thank you so much, Sarah. I really, honestly, I cannot thank you enough. You're one of the busiest people on the planet. So I do appreciate you giving us this time, it's going to be a huge episode. I'll say goodbye now. And we'll be in touch very, very soon. Thank you so much for listening to today's episode. I hope that it leaves you feeling inspired and motivated and ultimately happier. Don't forget to check out my website, train with tish.com to learn more about me and the services that I provide. I also train you for free. If you just check out the link underneath this podcast, look forward to the next episode until then live happily, be well and tell someone today that you love them.