Dr. Amy Shah On How Intermittent Fasting Creates Health Benefits

Hi and welcome back to the WellBe Show and Podcast. This is your host, Adrienne Nolan-Smith. Thank you so much for joining today. I am very excited to have Dr. Amy Shah. She’s double-board certified in internal medicine and immunology and a nutrition expert to talk to us today and answer all of the questions you might have ever had, or even if you haven’t, on intermittent fasting. Amy, welcome. Thank you for being here. Adrienne, thanks so much for having me. Well, I just have so many questions for you. I can’t wait to jump in. I was loving everything that I read about you and heard about you before this interview, so I’m just wildly excited that you’re here. I’m so excited. I’ve been watching your stuff on social media also. I’m very impressed. Oh, thank you. Thank you so much.

00:47 - I asked most of the experts I have on the show this question because most of them have taken a bit of an untraditional path but I have to ask you, doing both board certifications, going to Columbia and Harvard for medical school and residency, what made you then stray from your conventional healthcare training? Like so many people, when I was in my 30s in my early career days when I was opening my practice, I had a crisis, like a mental and physical health crisis and I didn’t know what was wrong with me and I didn’t have anybody to turn to and didn’t have a tool kit. I don’t think any of us are given a tool kit like when things aren’t going right, so I was extremely tired all the time. I was feeling anxious all the time. I couldn’t sleep at night because I would have these nightmares of what could go wrong with all the things I was working on. I had two little kids that I never felt like I could spend enough time with but then, when I was at work, I felt like I could never spend enough time doing my work and so it was this constant feeling of not being enough for anyone. And physically, I was feeling bloated. I was gaining weight. I was feeling tired, like I said, and I just didn’t know what was wrong with me, so I came into this wellness world through my own personal crisis and really, what I realized is none of us are given the tools to manage our mind and our body because if you can’t find anything on the labs, Western medicine is pretty much at a loss, right? I went back to my nutrition roots from undergrad and looked at the research and I came up with my own plans, which I failed, I think at least 10 to 15 times with all these different things I was trying because when you go on the internet, you get all these suggestions and you look at the studies and you’re like, “Oh, this sounds good.

This sounds good,” 02:45 - and I didn’t know how to heal myself until I found a few things that really did help and I felt that I had the need or I felt like if I could heal myself that I needed to share it with others, I thought maybe I would write a book someday but with the rise of social media and blogging, I submitted an article to mindbodygreen, which I know you’re familiar with as well, and I think there it was like seven or eight years ago now and they accepted it and I was so excited because it was a creative outlet for me while I was trying all my crazy things to myself -- to try to heal myself – and over documenting my journey, I entered the wellness world, which luckily now is so mainstream and that’s really how I got out of conventional medicine. I mean, I still practice and I still see patients traditionally and I never really left that part of my life because I think there’s a role for both in our health and I’m not the anti-doctor person, not only just because I went through all the training and certifications but because I think there’s a lot of value from having that experience and that background because I can read research articles critically. I can try things and know that just one little observational trial, doesn’t mean that it’s actually good for everyone and I understand the human body how it works, so I think that I was in a unique position, so I’m happy that I’m able to share that in a “2020 way”, virtually through social media, blogging and conferences and talks, so I’m really blessed. Great. I know that you mentioned, when I read your biography, that you’ve had this car accident, right? And it made you realize that you needed to do this full overhaul of your life and what would you say was the hardest part about making changes in your life after coming to that realization? Because that’s something, it doesn’t matter if you’re a doctor or anybody else that that’s really challenging to do -- to change your lifestyle behavior and your patterns and your habits. Had you been thinking that maybe you wanted to make changes before the accident and hadn’t stuck? What did you do when you decided to make these changes? That’s a really great question.

05:06 - I think I wasn’t allowing myself a space to even know that I wanted to change because I was in constant… I know you can relate because you lived in New York City just like me. It’s like you’re in this constant race in your head to get to the next place on a daily basis and then, in your mind, you’re constantly thinking about the next level on a monthly, yearly basis and you never give yourself any down time to really think about the big picture and I think when I had that accident and I was forced to slow down for the couple weeks after, I realized I need to make a change and I can’t just let the day-to-day kind of whirlwind of a life take me away from what are my long-term goals, like I want to be healthy and happy and I wasn’t. And I think that that’s what motivated me. It’s just to slow down and take a few minutes to realize.

06:01 - I tell people this all the time now when you’re really trying to evaluate your long-term goals, you have to give yourself space to even think, even if it’s for 10, 15 minutes a day. Maybe, it’s getting your morning outdoor sunlight, which we can talk about later and maybe, you just spend a couple of minutes in gratitude with mindfulness kind of thinking being happy where you are and kind of thinking about the future and how you can be a better person. I think that if you don’t give yourself that time, a space or bumper in the day, you’re going to be wrapped up in this rat race, which is leading nowhere. Yeah. I would agree with that. Both in my previous life working within the health care system and other jobs in New York City and now, even when I’ve left it, but I’m still running my own business, that resonates because you can just… get always wrapped up in the next thing and rushing-rushing.

06:59 - Now, I want to ask you a bit of about your work with patients. You work a lot with individuals who are struggling with inflammation, food sensitivities and weight gain and what would you say are some commonalities that you see among them. What are common root causes of their health issues, for example? My book, that’s coming out actually in March of 2021, is called – Oh, congratulations. That’s so exciting. - Thank you. It’s called, ‘I’m So F-ing Tired,’ because if you look at everything across the board, there are so many different ways it can manifest but what the number one thing that people talk about is being tired all the time, whether it’s tired mentally and emotionally tired or physically tired. Sometimes it’s completely intertwined, so that’s one thing I see all the time and the root cause of all of this is that there is an imbalance in our energy trifecta.

07:54 - I called it energy trifecta because gut health really runs the show for us in terms of immune system and hormones, so it’s gut health, your immune system and hormone health and they’re constantly communicating with the brain in the middle there and what’s happening is your gut bacteria talk to your immune cells and they basically decide if they should create inflammation or if they should let this food through and just take vitamins from it and create hormones from it. We’re constantly… At every point in the day, we’re constantly in communication… the gut bacteria is in communication with our immune cells, which are in communication with our brain and our hormones and so, it’s all like a nice, tight balance but as you know, with our diets today, our gut health can be quite disturbed. Our gut bacteria balance can also be affected by our lifestyle. Our hormones are constantly being affected by late-night stressful days and eating foods that imbalance our hormones and using products that imbalanced our hormones.

09:04 - When this energy trifecta is imbalanced in any one of those sides, the whole thing is off balance and people feel tired, is the most common symptom and then they feel bloated and they feel symptoms of anxiety or mood changes or low-mood, for example. That makes a lot of sense. Obviously, we’re going to talk about intermittent fasting today but how did you discover… in this work with patients and your understanding of the gut and the hormones and mental health and this exhaustion, how did you decide to become an expert on intermittent fasting? That’s a good question. If you think about what we can really do to balance this trifecta, this energy trifecta, if you think about the few changes you can make in your life that would help with your gut health, so one is, of course, eating foods that are good for your gut health and we can talk about that. The other thing is circadian rhythms. What I discovered from the research -- and it’s so fascinating – is how circadian rhythms are related to our hormone health.

10:12 - They’re related to our gut health and our brain health. Circadian rhythms literally help our body get balance. Eating with circadian rhythms became something that was quite interesting to me because it made sense that less than 100 years ago, we did not have late-night eating options. There’s no refrigerators and TVs and people weren’t popping late-night eats all the time. It was basically once the evening came around, you turned down the lights, you didn’t have refrigerators and you were kind of done eating for the evening and the studies show that your body thrives on this kind of eating and then fasting – eating and then fasting, which is very natural and you can really improve so many things, including gut and immunity and brain and hormone health just by following this circadian patterns with eating and sleeping and that’s what really got me interested because I said, “Well, these are kind of easy switches that I could make to my life -- getting sunlight in the morning, getting a little more darkness in the evening and stopping my food two to three hours before bed and not eating until the next morning.

It seems like it should be super easy,” 11:30 - but if you look at the American population, they eat about 15 to 16 hours a day on average. That means there’s only eight hours left, so that’s basically sleeping time and that’s way too much for our gut and our cells to handle as is seen by our disease rates for diabetes, for heart disease and the biggest study that changed my mind was in 2012. There was a SAC Institute study, where they took two groups of rats and they put them on two separate diets. The diet quantity and quality was exactly the same, so the same number of calories, the same kind of food. The only thing they change was one was allowed 24-hour access to food and the other one was only allowed in a time-restricted fashion, meaning that they could only eat during their waking hours and then they were fasting for the rest.

12:22 - And what they found very shortly, and this was about 12 weeks later, is that one group of mice -- the mice that were eating ²⁴⁄₇ – got all the diseases of modern life: obesity, diabetes, hypertension, heart disease, brain disease. And the other group was not suffering any of those diseases, so they were shocked because they’re like, it’s the same bad food, they were fed the same high chow that was like high in sugar and high in trans fats and whatever but there was a huge difference in their health outcomes, so they repeated the study. Their study has been repeated about 12,000 times now because it was so surprising to people that this would be the case – just by restricting their time – then they were able to reproduce those results. Then the SAC Institute did a study on humans and they found the same thing. If you restrict people to eating for 10 hours a day with a 14-hour fast, you were able to stop them from getting the diseases of modern, Western life and that really made me think, “Okay, this is something that I’m willing to try because it would make me feel more energetic.

13:28 - It would improve my sleep quality, per the studies,” and it started to really improve my own personal health, which is why I talk about it so much. I love that. Thank you for getting right into the research. I’m a research junkie myself, even though there are issues with some research but I think it’s so fascinating when you can talk about an issue and then talk about what the findings were that made you decide to make that a part of your practice or something that you’ve really dedicated so much of your time to and become an expert on. I realize, we might need to back up a tiny bit and I think you’ve explained it actually pretty well but what would you say is like the simplest breakdown you can think of as far as what intermittent fasting really is for anyone who’s not familiar with it. I think it’s just time-restricted eating but is there anything more to it? Adrienne, great question. Intermittent fasting was the most Googled diet in 2019.

14:24 - There are so many different definitions on the internet, so it’s quite confusing. Time-restricted eating and more specifically, circadian fasting, which is what I was referring to, is a very small subset of intermittent fasting. Intermittent fasting basically means any kind of rest from food for any length of time. Really, it’s a very wide definition but in the most specific sense, that I’m talking about, it means taking a break from food from dinner to breakfast and that sounds intuitive, right? Dinner to breakfast, like shouldn’t we all be taking a break and I feel that it is intuitive and it is something that we should recommend to pretty much everyone, however, it has not reached the medical mainstream and most people are still clueless about what circadian fasting even is and why anyone would want to do that. That’s so interesting. And yes, it makes so much logical sense to me but I imagine, at least in my case that the issue is with the high stress, high activity life that a lot of people are living today, dinner ends up being later than planned because of getting home and school and chores and work and so, you finally get it on the table and maybe, by the time you’re done eating and then you’ve got a really early morning and so, you’re eating something in the early morning and so, that window becomes smaller, so people might say, “I am only eating dinner and breakfast,” but the problem is that dinner is so late and breakfast is so early.

15:56 - How do you advise people on that piece of it? Adrienne, great question. This is a big issue because I was the same way. When I read this research, I was snacking, probably had my final snack right before bed and then somebody told me, Bro-science told me years ago that I was supposed to eat first in the morning to get my metabolism going, so I would want to eat something first thing in the morning and my window was quite short. But what I realized is that most people can make small changes to their life to complete this, at least a few days a week. For example, someone who is busy I might say, just try 12 hours on the days where it’s really difficult but there maybe two days in the week or three days in the week where you can push it to 14 hours or 15 hours and work up to that place and so, maybe that means ending your meal at seven couple nights a week and not eating till 10 in the morning.

17:00 - And like I said, it’s a small shift and you may have to move things around but almost everyone I talk to can fit this in a few days a week and then do 12 hours or 12 to 13 hours on the other days a week, so it’s not talking about huge shifts to your life, so eight to eight, seven to seven – 12 hours – and then the other days, you try to push it a little more on the days where you have to fit someone’s lifestyle, so maybe more opportune on certain days than others. Okay, thank you for that. There were two things you said that I really have more questions about. One is this idea of doing it just a few days a week. Can you explain why that’s better than not doing it at all or why that still effective if you can’t do it seven days a week? Okay, a couple of things. One thing is that, Ruth Patterson study, done on breast cancer survivors.

17:55 - They looked at just 13 hours of fasting, so everybody was on 12.5 hours or 13 hours and above and they looked at two groups of people with breast cancer. They found that the group that was not fasting at all had a 36% higher chance of breast cancer recurrence than people who are fasting at least around 12.5, 13 hours a night. What she said is, “I wanted to give an intervention that was really easy for our patients because breast cancer survivors are people who may not want huge shifts to their lifestyle,” and what she had read in the literature is that maybe 13 hours was kind of the minimal time and what I’ve found in my work is that 12 hours is when things start to change for you, 13 hours, the Ruth Patterson study and then 14 hours is a SAC Institute studies and then 15 and 16, you just keep getting more and more benefits and so, what I realized is that you can alternate. You can go just 12.5 hours on nights and then you can go 16 hours one day when you really are feeling it and still get benefits from it and so, it doesn’t have to be all or nothing.

19:14 - Just like anything in life, like I think we’re so you used to be all or nothing in our health approach and it really doesn’t have to be, you can tweak it to your life and we start getting benefits from 12 hours onwards. Okay, great. Thank you for that. And then the other thing you said was that you were taught, as was I, that you want to eat first thing in the morning but also that you want to eat a big breakfast. That breakfast should be like a king and lunch like a queen and dinner like a pauper, which it did kind of make sense to me because when you think about digestion, why would you want to have a large meal at the end of the day when you are then maybe not able to digest all of that by the time you go to sleep but how is that not true? Or how can you, you know…? How is intermittent fasting so helpful but is this still true and how do you deal with that? How do you reconcile the two is exactly what you’re saying, yeah. The reconciliation is switching your patterns to fit that eastern and western medicine can agree on one thing that the middle of the day, between 12 and 5 is your peak digestion time and if you can fit as many of your calories during the peak digestion time, the better it is so that means early in the day, you want to have the most of your calories and I am a huge believer in breakfast – believe it or not – even though I’m FastingMD on Instagram and the reason why is that if you do a circadian time-restricted eating, like a circadian fasting, then you won’t have to skip breakfast.

20:50 - It will maybe, be a slightly delayed breakfast first thing in the morning but it will still be a breakfast and the benefit of that is that we have very good insulin sensitivity in the morning. We know that eating the same food for breakfast, the same food at 10 pm is processed so differently by our bodies and we know that late-night eating has huge effects on our hormones, so we’re very insulin-resistant late into the evening and so, what I suggest for people is when you intermittent fast, timing does kind of matter. You want to eat your meals as much as you can during the peak digestion hours early in the day and then weaned down your meals in late in the evening and stop eating two to three hours before bed, at least. For me, that’s naturally like 7 PM -- ending your meals at 7 PM – and going to bed around between 10 and 11 is very natural and very good for your body. If you start fasting at seven, you don’t need to do a long morning fast because you’re already been fasting for 12 hours even by 7 AM, so you may want to eat breakfast at 8, 9, 10, 11 and all of those times are appropriate and depending on where you are in your journey, you still will be having breakfast. Got it.

And if you think about breakfast is just when you break the fast, 22:19 - so any meal you will have after you break the fast is breakfast, right? No matter what you choose to eat at that time because… I love how Americans and I think a lot of cultures actually have like such a set idea of what breakfast is, like having greens and vegetables for a lot of people it’s like, “What?” but technically, you could eat a lunch-style meal for breakfast as long as it’s the meal that you’re breaking is your fast, right? 100%. I’ve got so many more questions. Each time you answer one, I’ve got 12 more. Do people all have the same circadian rhythm and if not, when they break fast or start a fast and how long they fast have anything to do with their unique rhythm or should everybody kind of get on the same time patterns? Adrienne, a great question. Everybody has, as with anything in medicine and health, everyone is very individual. However, it’s quite conserved. There’s differences between 30, 40 minutes between people but not what we had previously thought that people are just night owls.

23:20 - It’s really a lot of the people that are night owls are simply night owls because they’re getting blue light exposure. They’re eating late into the evening and they just don’t feel tired at a normal hour. If you think about circadian rhythms, in our brain, we have a suprachiasmatic nucleus in our thalamus and basically, it is conducting kind of an orchestra with our hormones and the rest of our brain and it gets input from light in the morning. When you see daylight, these lux of light stimulate the special receptors in our retina. They go straight to the suprachiasmatic nucleus and tell it, “Oh, it’s morning.

23:59 - Get everybody on par with this is morning,” so it’s like the suprachiasmatic nucleus is telling of hormones, the GnRH, the gonadotropin-releasing hormone is pulsing. It’s like, “Oh, we see it’s morning,” and it sends signals all over the body to start doing morning type things, which is metabolizing food, which is doing the things of daily life because our cells cannot be doing everything at once. In the morning, they know that it’s time to stop the repair processes and start the metabolic processes and that’s why night shift workers have such poor health outcomes because no matter what, your body is attuned to the light and starts to do the things it’s programmed to do during the daytime and it’s not programmed to sleep during the night time, so then in the evening, about three hours before bed, you get this melatonin secretion and the melatonin is telling our organs, “Hey, it’s time to sleep.” It’s not just telling our brain. It tells our brain but it’s also telling our pancreas and our intestines. In the pancreas, it has melatonin receptors that actually tell it to turn down the insulin production.

25:13 - It’s telling the body, “Hey, it’s time to turn on those repair processes,” and when you get a burst of blue light -- one burst of blue light – delays that melatonin by about 90 minutes and so, you can imagine in our modern world, where we go to the grocery store late at night and then we go somewhere and we’re blasting the TVs and computers, we’re going to have delayed sleepiness, which can shift our circadian rhythm and then things aren’t working as properly. The long answer to your short question really is that we do have individuality, of course, in our circadian rhythms but it’s not as big as we think. Everyone is on a 24-hour cycle. That is dictated most significantly by light input and then secondly, by temperature and food intake, so your body is getting a couple of inputs to start the processes but the strongest one is light and then food and temperature and a couple of other things are secondary circadian rhythm drivers but we’re all on this 24-hour cycle and we’re all getting the same kinds of processes going at certain times of the day. Does that change in areas of the world that have very little light exposure or during the winter months or the summer months when maybe the day is so much longer or so much shorter. That’s a great question. Yes, it does change. We are… Again, the light and dark cycle is such a huge driver of our hormone and our brain and our gut health that we definitely can take that into account when we’re changing our fasting times during certain times of the year and so, yeah, you do have a little more leeway if you’re living in the northern hemispheres in the summer, for example.

27:00 - What I usually say for people is that, “It’s good to cycle your eating seasonally, just like it’s good to cycle anything seasonally.” Your food intake, your different types of vegetables that you’re eating and I also think this is something that we didn’t get into yet but we should – women can definitely modulate their fasting according to their cycles and so, we can do a lot of little modulations throughout the day, weeks, months and year that can fit our biology a little bit better. Oh, interesting. Okay, because of course, I’m such a program person that I want to have like, “Okay, every single day, I eat dinner at this time”, just to make it… I think you got so many things going on in your head sometimes, having these things you don’t have to think about makes it easier but… I think, Adrienne, you’re right. I think in the beginning, I tell people just start with 12 hours. Start from seven to seven and just go…

28:02 - Leave it from seven to seven minimum and then feel yourself out. Once you start getting used to it, you might say, “You know what? I don’t need to eat right this minute,” but I’ll go work out first and then eat, and you naturally get into this rhythm of always having a set 12 to 13 hour of fast but then you kind of increase it as it feels right for you on certain days. Got it. Yeah, because I do struggle with that. I find that I’m not often very hungry in the morning but I sort of force myself because I think I should be eating a good breakfast and getting on with my metabolism and digestion and blah-blah-blah and it’s so funny to turn that on its head now and say, “If I’m not hungry yet, it’s actually good to wait a little bit till I am,” because each hour apparently has more and more benefits, so that’s actually funny to just completely reverse that whole process in my head. Let’s say that the sun rises in my area at 6:30 right now. How late is too late, maybe, from when the sun rises to when you might eat your first meal and same with the sunset, is it wonderful to time it exactly with that? You know, the sun is fully down at eight o’clock to eat at eight o’clock or earlier? How does that work? That’s a great question, too.

29:20 - I do think that it is fun and beneficial for your body to time it approximately. For example, I tell patients that getting morning sunlight input into that retina, to the suprachiasmatic nucleus before 10 AM is ideal because if you think about it, that is the right time to tell our bodies that, “Hey, it’s morning. Start doing all the processes.” They benefit of just about natural sunlight, just going outside for two minutes, getting that natural sunlight into your eyes and it’s not just your eyes. It’s through your cells – skin cells – they are all detecting this light. You’re able to start so many of these beneficial processes in your body that there is great benefit in trying to coordinate that, if possible.

30:15 - Now, as you know in America, in all over the world, people are working all different hours and I get questions constantly from night shift workers or people who are working a second shift or third shift about how to do it for their lifestyle. You have to kind tweak it. Not everybody is able to go outside at 6:30 AM and get a bout of sunlight and if you are, you are blasting, do it and if you can’t, even if it’s a cloudy day, that natural sunlight, light that’s overhead is about 200 to 500 lux of light. Light that’s outdoors is 1000 lux of light, just on a cloudy overcast day. And 10,000 lux of light on a bright, sunny day. You can imagine there’s a big difference between just turning on your lamp or your overhead light and actually going outside and getting that input, even though it’s an overcast and even before sunrise, right before sunrise, there’s still enough lux of light to stimulate this process in your body.

31:15 - If you think about it, we’re evolutionarily created to get natural sunlight into our bodies and little did we know, until recently, how important it is to our bodies to create this kind of rhythm. Stopping food before bed… there’s a 2019, actually, New England Journal article that showed that actually the food… stopping food, your body senses that, “Oh, there’s no more food coming in,” and they start to do all these repair processes and there’s this amazing switch, this fuel switch that happens during a fast that is totally unused by so much of our population. Basically, what happens is you first use sugar for fuel. That’s our preferred source of fuel. Once we use all the blood sugar, we go to our liver because we have stored sugar as glycogen in our liver.

32:09 - Once that glycogen is used, at about 12, 14, 16 hours, we start to go into this amazing metabolic switch. It’s a fuel switching from sugar for fuel to fatty acids from fuel and once you get into this using fatty acid for fuel and then in the morning, say, you break your fast and you’re back to glucose for fuel, the switch back and forth turns on all these genetic processes that we think are evolutionarily conserved, so better mitochondrial biosynthesis, like we want more mitochondria. We want more stress resilience. The cells become more stress-resilient. The body becomes less inflamed, so basically what’s happening is this fasting is creating this switch in our bodies -- this metabolic switch – which are then creating all these downstream changes, which in turn is increasing our longevity, it’s increasing our mitochondria in our cells, and it’s increasing the stress resilience of our cells, so it’s anti- aging. If you think about it, I equate it to people similar to exercising, so there’s direct benefits of exercising but you know and I know that there’s always downstream benefits of exercising – mental health benefits, anti-aging benefits, cellular health benefits and now we’re realizing that intermittent fasting is the same. My next question was summing up the main health benefits of intermittent fasting but you just did.

33:38 - Are there any others that you can include in that because the ones you said were already pretty incredible? Exactly. Longevity is one of the main interests in intermittent fasting and we’ve seen many, many studies with longevity benefits in animals. We’re still doing the human studies because obviously, longevity studies are hundreds of years long and intermittent fasting, as a concept, is a newer concept, at least as a medical study. I was going to say, I know it’s not a double-blind clinical trial or anything but I’m obsessed with the blue zones and one of the commonalities that they were able to discover -- they being Dan Buettner and National Geographic between the five blue zones of longevity. There’s a handful but one of them is that they all fast in some way, which I thought is very interesting.

34:29 - Yeah and medical science is not caught up to this because there are some opposing studies. Of course, whenever you do a lifestyle change and you look at different studies, like a new study just came out that looked at intermittent fasting and they were randomized, double-blinded and controlled and they put it into different groups, and the intermittent fasting group was told to fast for 8 PM to 12 noon which is not the ideal times in my eyes but that was what they decided and they found that they did lose a little more weight than the other group but it wasn’t significant. It was like 0.93 versus point 0.63 pounds and they deemed that intermittent fasting is not useful in weight loss. My takeaway from that is it is not a get-thin-quick weight-loss strategy. What I’m doing it for is the digestion benefits, the brain benefits, the inflammation benefits, the mitochondrial benefits, the longevity benefits and you know what? If I can stay lean and healthy as a side effect from that, great but I’m not using it as a primary weight loss tool for my patients because we’re still not sure, is it the timing that matters, which is what I believe, maybe moving those people up to eating at dinner at six o’clock or seven o’clock and then not fasting all the way to noon but shortening that fast and improving the quality of the food, so we don’t have the information yet to make it a slam dunk for weight loss.

35:52 - As we know weight loss is the very difficult task but I do think it has many, many benefits beyond weight loss that make it such a great tool for so many people and, Adrienne, my biggest takeaway for people today is that it’s not about finding that next diet for you, that secret, that shortcut. It’s about finding something sustainable, easy and those small incremental changes that are going to make huge health benefits later and this is one of those things. This is not a diet that I’m prescribing to people. This is not something that’s going to give you instant tomorrow results. It’s something that’s going to give you small, incremental benefits, both now and in the future and it’s something that is not a huge shift to most people’s lives if you’re really willing to put your mind to it. Yeah.

I was just going to say it’s certainly not research but anecdotally, 36:52 - a cousin of mine who had long struggled with her weight, I encouraged her to see a naturopath. She really wasn’t familiar with any sort of integrative medicine. Maybe like acupuncture here and there but not as her primary care doctor and he put her on this very regimented food program and she was doing it very diligently and after a couple weeks, she had a lot of weight to lose and she was only losing about a pound a week and the naturopath said, “This seems crazy. I mean given what I’ve laid out for you, you should be losing a lot more than that. I think your metabolism might be shot”, so he introduced intermittent fasting to her program and the weight just fell off.

37:33 - It was really wild and so, when she said your metabolism was shot and then I started intermittent fasting, I still wasn’t really clear the connection between a shot metabolism and how intermittent fasting is going to help but you’ve explained it a little bit. Do you mind breaking it down a little bit more? Sure. The simplest way to think about it is that intermittent fasting is like exercise. It’s a hormetic stressor. A small stress to our system has huge benefits in the rest period. So if you think about it just like exercise, you know, you lift weights and the benefits are maybe in the regrowth period, in the rest period, where the things are regrowing and the same thing is like you throw a hormetic stressor to your body and your body says, “Oh, what?” like you know, metabolically, it’s like lifting weights, like, “Oh, she’s just intermittent fasted.

38:28 - Let’s create metabolic changes to help her with that,” just like we do with exercise. Your body says, “Oh, Adrienne is lifting weights now. We’ve got to get this bicep stronger so it’s easier for her next time,” and the same thing, I would say, with intermittent fasting. It’s a hormetic stressor. Now, remember, just like exercise, hormetic stressor can be too stressful in the wrong dose for someone. First day, you go to lift weights. You’re not going to lift 150-pound barbell and that’s why people fail at intermittent fasting all the time because they go, “Oh, I read somewhere 16:8, so I’m going to do 16:8 every day,” and that’s like running 12 miles on your first day.

39:11 - You’re going to feel exhausted, depleted and your hormones are going to be all over the place. It’s not the way to go. That’s why I say that hormetic stressor can be a great thing for the metabolism, like you just alluded to, hormetic stressors are great for our health, so saunas are hormetic stressor, exercise is a hormetic stressor. Intermittent fasting can be a hormetic stressor but in the wrong doses, it can be too stressful. That’s how it really can help the metabolism, though. Got it. That’s such a great explanation. Thank you so much for that. You just mentioned something that now I want to ask you a question about – exercise.

39:47 - If I’ve ever fasted, I’ve found that sometimes, it’s fine and I’m not really hungry until I want to break it but other times, I’m actually hungry and it’s a bit of a struggle and then I’m feeling a little bit faint and I know that if I don’t exercise in the morning, the chances of it actually happening are less and less likely every hour that goes by and exercise is so important, as you said, so how do you handle the whole sort of maybe fasting when you wake up but trying to exercise and then feeling a bit faint as a result and then, perhaps, not really wanting to exercise because you feel a bit faint. Adrienne, the same exact analogy as if you’re starting a new exercise program, right? You want to take it very slow and easy in the beginning. One thing I didn’t mention here is that a fasted workout is a great way to turn on that metabolic switch, especially if you are doing a shorter fast because you can use up that glucose faster if you’re working out and you have better chances of getting that switch to using fat for fuel but that can be very gradual. You can go 12 hours and do some stretching in sunlight and then break your fast and then maybe, Week 2, you add in some steps in the morning. Maybe, Week 3, you add in a light workout.

41:02 - Most people that have never done this before, you’re not going to be able to do a full hit workout fasted right out the bat because your body is so used to using that sugar for fuel. That, when it’s run out of that sugar and glycogen, it starts to like freak out because it’s never done that before and we’re so metabolically inflexible in our life. Think about it. When I learned about this fuel switch, I thought about how many people may have never experienced the fuel switch because they’re always in the glucose -- high glucose state – and when they get low on the glucose, they start to feel a little bit down because it’s like a muscle – a metabolic muscle – and it’s really weak. We’re weak in the beginning and we’ll feel all those effects. You’ll feel tired, you won’t feel like working out, you will feel low because you’re craving that sugar, because you’re used to having sugar for fuel.

41:54 - But once you attain that metabolic flexibility, you’ll be able to go back and forth a little bit easier. I love that. Okay, so it’s just like you said, it’s training for any new thing. We can train ourselves to little by little take on more exercise on an empty stomach, even if initially, we feel like we have no energy to do it or we feel faint or something like that. Yeah. It’s like a weak muscle like, you know, in the beginning, you’re going to be like, “Well, I can’t lift that weight because my body won’t let me,” and that’s okay but that can be trained and you can lift more weight over time. Got it. I do morning yoga and morning Pilates on empty stomach and I feel that’s fine.

42:35 - It’s doing any sort of cardio, where I feel like, “Ugh, I don’t have enough energy,” but maybe I could just try like a 10-minute run or something, so just slowly see how I do with that on an empty stomach and work my way up. Adrienne, think of yourself like the Kenyan marathon runners. They’ve used fasted runs for many, many years as part of their training regimen because they know what we didn’t know before is that if you train fasted, you get your body stronger to handle when it runs out of glucose for fuel and so, they were teaching themselves without even knowing about this fuel switch to train their bodies to handle long ultra-marathon runs without bonking. That is something I didn’t know and that’s so interesting. Wow. Okay. Okay, we’re running out of time. I can’t believe it but I have just a handful of questions left for you.

43:31 - One thing I want to touch on because I think this is confusing. There is liquid. I’ve heard of bullet proof coffee. My older brother is interested in intermittent fasting but he always would do the bulletproof coffee, which is coffee with either some sort of tea oil or something like that and I would say that’s not a fast. He said, “Yeah, it is and coffee is allowed.” Then there’s a blurred line about what is just coffee? Is a latte coffee? And you can kind of snowball from there, so what do you think about liquids and also, alternatively, the people having maybe things like wine after dinner or tea after dinner or something like that. What is the deal with liquids and fasting and when can you have them and what kinds and all of that? Great question. There are so many different types of fasting.

44:17 - There are things like modified fasting regimens or fasting-like regimens, which is what bullet proof is. It’s fasting-mimicking regimen, where you try to keep yourself in that fat-burning zone, that ketone zone, for a little bit longer by having only fats and that’s something that’s interesting. However, I would say that that’s not the cleanest way to do a fast, so you’d consider it secondary, not like a circadian fast that I would say, would be only water, tea, coffee, sparkling water, any non-caloric drinks but no artificial sweeteners. What I do allow, because there is some benefit to give people some alternatives when they’re struggling, is that you can do a splash of almond milk up to 40 calories or in the evening, you can do a half of teaspoon or a teaspoon of almond butter or like a little tiny slice of avocado, like 40 calories, are allowed either in the morning or late in the evening to get you through those first few weeks or whatever it is or when you have kind of underate and you’re thinking, “Okay, should I break my fast by eating a full dinner right now or should I try the strategy of like taking a little bit of fat in and seeing if I can kind of keep it going for a little bit longer.” Those are not the ideal situation. Ideally, it would just be water and sparkling water or any kind of zero calories, zero sugar items or in the situation where you’re struggling and I’ve done this a thousand times, so that’s what I recommend to people, is you still see benefits with a splash of almond milk in your tea in the evening or in the morning and a little slice of fat because if that is all you need to get through it, then you’re still getting so many of the benefits.

46:10 - In fact, we think that 50 calories is kind of the cutoff. You know, all of this is still to be continued with science but from experience, I think Dr. Fung, also in his clinic, he does longer fasts and he does allow for about 50 calories during the fasting period and then there’s all these alternative fast that you can do, which are kind of like fasting but when I’m talking about circadian fasting, I’m talking about water, sparkling water, tea in the evening, maybe you’ll have a teaspoon of nut butter just to get you through and then you’ll have your coffee or tea in the morning, then you’ll break your fast. Okay. Because I currently take a coffee with a little bit of organic oat milk on a walk-with-me and I do meditation before my breakfast, so if I could include that in my fast, that would be awesome and it sounds like a little bit of oat milk or almond milk or something with coffee is okay which is great news, I’m sure for other people as well. Okay, so second to the last question for you. Is there anybody…

Is there any kind of person 47:16 - or group in the population that should not be intermittent fasting? Is there any particular condition or something where you would advise against it? Many conditions, actually. Just like any health measure, you really do have to check with your physician. Even though I’m a doctor, I’m just giving kind of general informational advice but any diagnosis really, if you have diabetes, if you have high blood pressure, if you have high cholesterol, if you are pregnant or breastfeeding, I mean, these are all reasons not to do intermittent fasting, especially with someone in pregnancy. They asked me about intermittent fasting and I’m like, “Woah, just wait till the baby is born and then we’ll talk,” because you’d never want to do anything that’s going to compromise the state of the child and when we talk about this fuel switch, we don’t know what the fuel switch is doing to the fetus and so, we always recommend that you wait till after pregnancy to do any kind of intermittent fasting. Same thing if you’re a very brittle diabetic.

48:17 - Brittle diabetic in medical terms means someone who has a tendency to run really high sugar and really low sugars. You know, someone who is not very well-controlled by just their food intake, they have to really watch their sugars very closely. That person should not intermittent fast unless they’re in close conversation with their personal doctor, they’re checking their sugars all the time – adjusting their insulin, so there’s a lot of nuance to this, definitely not for everyone at all. Someone who has an eating disorder or history of an eating disorder may not do well with something like this because this is just turning on those free wild notions of restriction, right? So we don’t want to turn that on again for a certain people. You know, the list goes on and on and on. It really does have to be personalized to the person.

49:05 - The way you described circadian fasting or intermittent fasting, at least, on the low end but it seems to me sort of intuitive and not like a stretch that you would probably go 12 hours, even when pregnant, right, between your dinner and your breakfast. I usually end up finishing dinner, let’s say, around 8:15 in the evening and I’m definitely not hungry for breakfast until 8:30 to 9:30 even sometimes. I feel like that’s almost not a change but rather, just a lifestyle that, you know… Adrienne, this is the problem with the internet. As you know, some people take things out of context and being a doctor, I really do have to be careful that I never kind of dole out medical advice but you’re absolutely right.

49:54 - It seems intuitively that you shouldn’t have any… Nobody should have a problem with just going 12 hours or whatever. - Right. It feels like kind of a basic way to live, right? Yeah. It really does and I think it lends itself well to public health recommendation, right? But still, there’s so much pushback and I know that some of that pushback is from food companies. They don’t want you to fast. This is horrible for their business. They want you to eat and drink late into the night and then, eat first thing in the morning.

50:22 - They make way more money on that concept of constant eating. They don’t want me to say, “Oh, you can’t have diets during your fasting period,” and there’s no medications that are going to shortcut this for you, so the problem with this in a public health perspective is that there’s a lot of change from the typical American routine and diet and it may be something that some competing interests may not be interested in doing and unfortunately, that seems to be the only reason I can think of that there’s so much pushback. You know, there’s also some people like when we started this conversation, you might have thought of intermittent fasting as something that’s much more extreme than what I’m talking about and so, I think that there’s also some people who keep thinking like, “Well, we don’t want to introduce this type of restrictive eating into the culture,” but as you can see now, the real conversation is something that’s very intuitive and very evolutionarily conserved and very good for our health. Absolutely, yeah and I certainly did think about more of the 16-hour type fast than the 12, 13-hour type fast and it’s also great to know that even for people that you’re recommending it for, that you’re not necessarily saying do the 15, 16-hour one seven days a week. Just really try to go for the 12, 13 hour as a lifestyle because it’s so evolutionarily sound and good for our long-term and short-term health but those who want to go a little bit further, that they make sure they speak to a medical professional about it or do it in a way that is safe and that they can handle and to recognize that it’s like training any muscle that you can work your way up to it, which I’m not sure I realized before and I’m glad to hear. All right.

So my very last question for you, which I ask every WellBe expert on the show is 52:19 - and I have a feeling intermittent fasting is going to be part of it but how do you #getwellbe? Get WellBe is our social platforms and the name of the website but it also really embodies the idea that good health takes work and it doesn’t just happen to you, especially, in this modern, very toxic world that we’re living in. What are the things that you absolutely cannot miss doing every day for your personal wellness, maybe it’s one thing or two or three things, in which you absolutely, no matter how busy that day is for you, you make sure to do. How I get well-be is getting a morning routine, where I get sunlight with a few minutes of mindfulness. It’s something I will never miss. I will miss everything else in my day but having peace in your mind and your heart is something that is going to help you not only physically but mentally and that’s what health is, right? Physical and mental health. That’s something I never, ever miss. All the other stuff is cherry on top. Getting a good night’s sleep is probably my second non-negotiable and having some kind of gut rest is probably my third non-negotiable. That’s how I get well-be. Okay, that’s wonderful. Thank you so much.

53:35 - I also am finding that my morning walk with a little bit of meditation or at least, just that kind of checking in with yourself, the way that you’re talking about earlier, is becoming a non- negotiable that I didn’t always fit in in the rush of the city life that I was living but it’s a little bit easier in the countryside and certainly, easier just with everybody working from home during COVID as well but it’s something I’m going to make sure to do as much as I can because it just makes such a difference in my life and my health and certainly, just in that day. Well, thank you so, so much, Amy for sharing. You really are just a wealth of knowledge on the topic of intermittent fasting and just a brilliant doctor doing a lot for wellness, both obviously, with social media and your soon-to-come-out book, which I’m excited about and then also obviously, with seeing patients and continuing this trend, which is a lot of the experts that I have on this show of conventionally-trained physicians from some of the best medical schools out there, seeing that there’s a vast problem with the way that we practice health care and medicine in this country and deciding to do something pretty risky and practice a bit differently and share the information that you have acquired in that process, so I thank you for that and for your work for public health. Thanks so much, Adrienne. It was a pleasure to be on here. .