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Felice Gersh, MD is a multi-award winning physician with dual board certifications in OB-GYN and Integrative Medicine. She is the founder and director of the Integrative Medical Group of Irvine, a practice that provides comprehensive health care for women by combining the best evidence-based therapies from conventional, naturopathic, and holistic... Read More
Cynthia is a nurse practitioner, author of the best selling book Intermittent Fasting Transformation: a 2x TEDx speaker, with a second talk having more than 10 million views, and the host of Everyday Wellness Podcast. She is a globally recognized expert in intermittent fasting and women’s health, and her mission... Read More
- Understand how intermittent fasting supports blood sugar regulation and lowers insulin levels
- Discover how women can successfully fast with their menstrual cycles
- Learn about the role of nutrition in managing PCOS
- This video is part of the PCOS SOS Summit
Related TopicsAnxiety, Baseline, Blood Sugar, Diabetes, Digestive System, Fasting, Glucose, Infections, Infertility, Inflammation, Insulin, Insulin Resistance, Intermittent Fasting, Lifestyle, Macronutrient, Metabolism, Nutrition, Oxidative Stress, PCOS, Perimenopause, Type Two Diabetes, Weight Loss Resistance
Felice Gersh, MD
Welcome to this episode of the PCOS SOS Summit. I’m your host, Dr. Felice Gersh. With me for this episode is Cynthia Thurlow, who is an expert in both women’s health and intermittent fasting. I can’t wait to hear what she has to say. So welcome, Cynthia. Thank you so much for joining me. And please share with everyone your own journey, because we were chatting just a little bit about it and I know everyone wants to learn about your journey into this field, and then we’ll do a deep dove into how fasting can help augment the health of women with PCOS.
Cynthia Thurlow, NP
Well, thank you so much, Felice, for inviting me to be a part of the summit. This is something that’s near and dear to my heart. And for many people who probably don’t realize I have struggled with PCOS my entire life, I didn’t actually know that I had PCOS until I tried to get pregnant with my first child and my very astute, wonderful Joy-Ann. I was using this temperature charting every day and I said, I don’t think I’m ovulating at these very long luteal phases. And she said, I think you’re a thin phenotype PCOS patient. And that is probably why you have flown under the radar and no one has figured this out. And why oral contraceptives were what were recommended to you? Because you had these very, very irregular, long menstrual cycles when you were younger. And so it started with that journey of infertility because of the PCOS. And ironically enough, it wasn’t until I spoke to my mom that I found out many women in my family have PCOS. Many women in my family have struggled with infertility issues. And so, you know, modern day medicine has a way to fix the problem with having low progesterone and a poor luteal phase or a luteal phase defect, as they like to call it. They give you medications. I took Clomid, I did IUD or insulin, intrauterine insemination with both of my pregnancies to become pregnant. And then we close that door on my fertility chapter. And it wasn’t an issue anymore. But what I came to find over time was that what’s really at the basis for PCOS is inflammation. Some degree of insulin resistance, some degree of oxidative stress. And because I was then no one ever thought to be conscientious about discussing this with me. And so when I talk about the fact that I was I was not diagnosed until I was 32, I think that this is a common thing that happens for women. Obviously, as I’ve gotten older, it’s something that I’m constantly kind of wrestling with because I’m at greater risk for developing things like type two diabetes. So it explains why I’m so conscientious about lifestyle. But then in my early forties, as I was transitioning into early perimenopause and I started struggling with weight loss resistance and some of the common symptoms you had trouble sleeping, more anxiety, you know, having tender breasts, very heavy menstrual cycles that it really reemerged that I needed to readdress why this was this is probably going to make it a little bit more challenging for me to navigate perimenopause unless I really dialed in lifestyle. And this is where intermittent fasting for me became a strategy that I initially used for myself to kind of work through some of the challenges that I was experiencing in early perimenopause. And then when I would go to work as a nurse practitioner, I would start talking to my patients and as many physicians and colleagues that were willing to listen to me, many of whom told me that they thought it was cute, that I cared about nutrition, and it was cute that I talked about intermittent fasting and I would say maybe a minority, maybe 10% of my patients are willing to embrace intermittent fasting. But for those who did, they felt so much better. They would say things to me like, I didn’t realize that my first thing that I ate in the morning was sending me on a blood sugar roller coaster for the entire day. I didn’t realize that the first thing I ate in the morning was what kind of set the tone for how I felt the entire day. And so when I talk about PCOS, I speak about it personally and professionally. When I talk about intermittent fasting, I feel like it’s one of many strategies that helped me navigate my middle age years. I’m now almost 52. I’ve got a birthday coming up in about a week and a half. And so I like women to understand, to have hope that even if you’re diagnosed with PCOS, it is not a life sentence. It does not mean that you can’t have a high quality of life. It does not mean that you will inevitably develop type two diabetes. If you are working hard to do the things in your your personal and lifestyle existence that will help lessen your likelihood of, you know, progressing on to significant insulin resistance and ultimately diabetes.
Felice Gersh, MD
Well, I did not realize we have so much in common. I had to self-diagnosed myself with PCOS. I used Clomid for my first pregnancy. My largest baby weight. £9, six ounces. Nobody could I get. This is a big babies. I know you’re too little, you know. So PCOS as a syndrome comes in many different, you know, experiences, expressions and so on and thinner women do make up not insignificant percentage of women who have to deal with PCOS. And they have many of the same issues. And, you know, you brought up already the whole topic of intermittent fasting. So let’s do a one on one here, go back to basics. So people use the word fasting in so many different ways. I mean, on a very simple level, you could say, well, fasting is any time you’re not eating. So maybe you could tell us a little definition, though, how you look at fasting and what is intermittent fasting. And then we’ll talk about other forms of fasting and what’s going on in the body when you actually incorporate this tool.
Cynthia Thurlow, NP
Absolutely. So when we speak about intermittent fasting, it’s eating less often. It is really that simple. I think we as a community, as a society, we like to overcomplicate things. And if we compare this to the information that I used to tell my patients and my background is in your medicine. Cardiology, I would tell my patients, eat frequently, stoke your metabolism. Breakfast is the most important meal of the day. And yet what we’ve come to find out is we actually benefit from eating less frequently. And so intermittent fasting really helps people understand that there is a time during the day in which we eat and there is a time during the day in which we do not eat. And the way that I like to identify this is you spend most of this time sleeping. You know, when people hear 6 hours fasted, they’re like, Oh my gosh, I can’t go 16 hours without eating. And maybe that’s not the starting point for everyone, but it’s helping people understand that, you know, after dinner until breakfast the following morning, most people are already going through a longer period of time of of eating less often. And so this really speaks to the fact that we are structuring our meals, whether we break our fasting 10 a.m. or 12 p.m., we are structuring our meals in such a way that we do not get hungry in between our meals. It is really changing the narrative in which many of us have grown up and certainly as a traditional allopathic trained provider for the stuff that I used to share with my patients actually makes me cringe because there’s nothing worse than saying Eat no fat, eat lots of heart healthy grains, don’t you know, don’t eat any animal based protein. You know, the vegetables aren’t important. And yet that’s the narrative that so many of us are sharing with our patients is that any wonder that our patients are so confused? So when we talk about intermittent fasting, there are different time periods. There are some people that will fast for 14 hours a day, 16 hours a day, 18 hours a day, or even longer. 20, 24 hours, several day fasts.
I know we are both bands and fasting mimicking diet. There’s, there’s a continuum in which we are talking about this intermittent periods of fasting. What is important is that there are different benefits from different types of fasting. So obviously 12 hours of digestive rest, which is really what I call it, that should be the mainstay for every single adult, irrespective of where they are in the world. We should be going 12 hours without eating, but that is so contrary to what we have been taught as we are, you know, getting to a point where we’re eating less often and we’re kind of opening up that fasting window. So maybe we graduate to 13 hours, 14 hours, 15 hours. The very basic things that are happening in the body is we are helping to reduce inflammation because we are not eating as frequently. Our body in many ways, if we are eating the standard American diet, we are eating a highly processed, highly inflammatory laden with seed oils, very low in protein, very high in carbohydrates in the process kind, which are not beneficial for our metabolic health as we are eating so frequently, we are not giving our body the opportunity to properly break down and assimilate food. There’s a really amazing process that goes on in our digestive system called the migrating motor complex. And so this is you can think about this as a street sweeper, much like, you know, if we’re pushing a broom, it’s a it’s a mechanism in our digestive system that will help move food along. But it actually, in order for it to be fully optimized, we need to go 4 to 5 hours in between meals. We need to give our body an opportunity to process what we have eaten and bring our blood sugar, our glucose back down to baseline before we are interrupting the process all over again. So this migrating motor complex can be interrupted if we’re eating too frequently. If we’re eating the wrong types of foods that can put us at risk of it’s not operating properly for opportunistic infections, which is something that I know Dr. GROSS really speaks about quite a bit in her practice. And so helping people understand that at a very basic level, this, you know, 13, 14, 15 hour, 16 hours of fasting can reduce inflammation and improve our biophysical markers. So every time we eat, depending on what type of macronutrient we are eating, so there’s protein, fat and carbohydrates. We know fat has the most negligible impact on our blood glucose, followed by protein and then carbohydrates. So if you are eating a, you know, nutrient dense diet, that is you’ve got plenty of protein and some healthy fats that’s going to have a more negligible response on your glucose than if you’re sitting down in a bowl of chips or a bowl of ice cream or you’re drinking, you know, high fructose corn sirup laden soda is like so many of the sodas that are out there. So it’s helping people understand that when we’re talking about the benefits, as we transition to intermittent fasting, it’s talking about different ways that we can fortify this practice. And so this blood sugar component, I think, is very important for most people to really understand that there is a way to put your macros together to stabilize your blood sugar. It’s I always say protein first, then we’re either adding in healthy fats. And if you sit down and have a wonderful piece of wild caught salmon, it already has those healthy fats and then adding non-starchy vegetables or you have a lean piece of protein like chicken, or maybe you’re having a filet mignon, which is a, you know, leaner cut of meat. Then you can add in some healthy fats. It might be olive oil on a salad. It might be some macadamia nuts. It can be a sliced avocado, as an example. But those are the types of food combinations that are going to help stabilize your blood sugar. And for many people, it’s the understanding that when your blood sugar is stable, you’ll have more mental clarity. You will definitely not have energy gaps.
And I think for many individuals, they’ve gotten very accustomed, not just after Thanksgiving dinner when they get sleepy because I’ve eaten so much food, but it has become the mainstay that the middle of the afternoon people are searching for soda and candy and coffee drinks because they haven’t eaten the right foods together at lunchtime. They’ve had this tremendous blood sugar. Probably their blood sugar went up quite significantly, then came down in a way that mitigates this, you know, postprandial blood sugar. That is not it creates symptoms of just feeling tired and fatigued and then moving on to the fact that not only is your blood sugar going to be better stabilized, provided you’re eating the right foods, but your body uses different types of fuel. And I think for a lot of individual meals, you know, we call them the sugar burners. That’s kind of the non technical term. But helping people understand that our bodies want to effectively use different types of fuel, we want to be able to use stored fat, we want to be able to use stored carbohydrate and we want to be able to use them interchangeably. But most individuals, they just keep topping off that gas tank. The best analogy I can make, I have a father who never likes to let his gas tank gets under three quarters of a tank, so he’s always topping off the gas. And that’s what’s happening when you are eating too frequently and eating the wrong types of food. Your body never has an opportunity to work through. Digesting what you’ve consumed before you’re adding more food in your body can actually go in and use stored fuel as a fuel source. So I think it’s very important for people to understand that when we’re talking about intermittent fasting, it’s getting to a point where we have this degree of metabolic flexibility where our body can decide, Am I sprinting and I maybe need some, you know, carbohydrate to use as a fuel source or am I going out for an endurance event or am I going longer periods of time without eating and my body can safely work through and tap into these fatty acids as a fuel source to be able to fuel my brain and fuel my body. Another thing that can become is this byproduct of metabolic flexibility is you can actually get to a point where your body can produce ketones. And I know that ketones are things that maybe people aren’t as familiarized with, but it’s another type of fuel substrate that the body can use. But what’s really interesting about ketones is that they can actually a special type of ketone called beta hydroxybutyrate when that is formed in the body, that actually will diffuse across our blood brain barrier. And for many people, one of the first benefits they will see from intermittent fasting is that they feel like they have tremendous mental clarity. And a great deal of that has to do with the fact that their brain is utilizing this specific type of fuel that is very fuel efficient. Our brain is full of fats. And so these ketones are very fuel efficient. It’s like turning on a light bulb. That’s one of the first things that people will say. I have so much mental clarity. I have so much mental and physical energy in this unfed state. And then we move on to things that are seemingly maybe perhaps less tangible, things like upregulation of autophagy that may not be happening at a substantial rate when we’re 14, 15, 16 hours faster.
But certainly the longer we fast, the greater the autophagy. And autophagy is this incredible waste and recycling process that goes on in our bodies. You want to think about it as your body is literally taking out the trash, getting rid of the, you know, organelles, mitochondria that have the potential to go on and create disease. And so this is one of those things that goes on behind the scenes. You’re not even aware of it, but it is something that’s very important. And again, when we start looking at rates of metabolic disease, rates of cancer here in the United States, and you realize that a lot of these are mitigated by lifestyle choices. And as unfortunate as that is, helping people understand that we want to make sure that the healthiest cells are what are surviving in our bodies. And this upregulation of this waste and recycling process is another thing. We know that intermittent fasting is helpful for neurocognitive disorder. So lessens the likelihood of developing Parkinson’s Alzheimer’s disease. If we think about it as take three diabetes, hundreds and hundreds of my patients have gotten off a blood pressure medication and they’ve gotten off diabetes medication in conjunction working with their health care practitioner. They’ve changed their lipid profile. So in many instances, lower triglycerides, improved HDL, perhaps improved LDL depending on the individual. So there’s a lot of different benefits. And certainly depending on the length of the phallus, there are different types of benefits that can be conferred. But those are definitely some of the, you know, the benefits of fasting and kind of the key components of fasting that I think can be very helpful for people to understand, especially if they’re newer to it.
Felice Gersh, MD
So that is a wonderful explanation of all kinds of very key information. And going back to typical patients. So I have many patients who were taught often by their nutritionist that they should be grazing all day and know that that was very much, you know, in the fashion about a decade or so ago that you have to eat like every 2 hours to maintain your blood sugar, which is kind of weird since humans will probably be long term, long extinct. Actually, that was essential. But a lot of my patients will say, you know, I get so hungry, you know, like I’m hungry all the time and I can’t go that many hours. Like, I can’t even sleep at night if I don’t have a big before bed snack. So for that kind of group and that’s a lot of people. So where do you start?
Cynthia Thurlow, NP
Yeah, it’s such a good question. And I think for so many people, it’s it’s giving them baby steps so that they master one step before they move on to another. So, number one, it’s helping people understand that they have to restructure their meals. So when someone says to me, I wake up in the middle of the night and I’m hungry or I’m hungry in between meals. The first thing I think about is we need to restructure your meals. So more protein. And I think especially for women, there’s this fear of protein. And whether or not that is a piece of fish, a piece of meat, a piece of poultry, or having legumes or having beans. The caveat with some of those plant based proteins is just being conscientious about portions, because a lot of the women that I work with are in perimenopause and menopause and carbs are not, per se, negative. I want to be really clear about that. But if you’re already prone to a degree of insulin resistance or loss of insulin sensitivity, you just want to be conscientious about portions that typically it involves more protein. So it could be instead of four ounces of fish, you’re having sex instead of four ounces of chicken, you’re having six ounces of chicken. If you’re doing a plant based diet, maybe instead of a smaller portion of lentils, you’re just measuring out a slightly larger portion of protein. But it’s also those healthy fats. Now, like I mentioned earlier, sometimes they’re already incorporated into a piece of fish, like a salmon versus a piece of cod ribeye versus a filet doc versus a chicken breast. However, or, you know, if it’s not already incorporated in that protein, I want to make sure that you’re adding in those healthy fats, whether it’s extra virgin olive oil, whether or not it is coconut oil, whether it is, you know, a high quality nut or seeds, those kinds of things can make a big difference. And so usually I find it’s the portion, it’s the portions of protein. It’s making sure they’re eating enough healthy fats.
You know, one thing that I think is super helpful for a lot of people to help understand when it comes to blood sugar stabilization, it’s not suggesting that there are bad foods. I mean, there are a couple absolutes that I usually recommend avoiding. You know, read those food labels. Be aware what seafood oils are, you know, those inflammatory, oftentimes rancid oils. Those are those are things I generally recommend avoiding. But having a piece of fruit is not going to derail all your hard work. So if you have a half a cup of berries, that’s not the end of the world. But that’s very different than having this highly processed, hyper palatable foods. The other thing that I find when people tell me that they’re waking up in the middle of the night and they are hungry, is having a healthy fat before bed. Sometimes this could be a tablespoon of MCT oil. Sometimes this could be a tablespoon of nut butter. Really depends on the individual. But sometimes that healthy fat can help with with stabilization. There’s obviously other things that we do. The other thing is when we’re transitioning from, you know, looking at the macros and tracking macros and there’s an app called Chronometer that I think is fantastic because it tracks my macros and also micronutrients. So, you know, potassium and minerals and things that are in our food and can be very helpful for people that are trying to become more aware of portions, but also understanding that we want to make sure that as we are transitioning from these larger portions of protein and healthy fats and non-starchy vegetables, there were also being conscientious about how are we going about movement or during the day are we going for a walk 10 to 15 minutes after our meals to help with blood sugar stabilization? Are we kind of slowly opening up this eating window in which we’re eating? So I don’t recommend if someone is struggling with blood sugar issues or blood sugar instability or just feeling hungry all the time. This is not the time to say I’m going to try to do a 16 hour fast. It may just be that you eat dinner at 6:00 at night and maybe you have a small little, you know, fatty snack before bed. And this doesn’t mean like candy. This is just a solid fat. I have some people that will just do like a butter cream. And by buttercream, I don’t mean the candy. They’ll just have a piece of butter. But and oil appears to be the thing that I think is most beneficial. But I think in a lot of ways helping people understand that when you wake up in the morning, if you’re struggling with blood sugar or some of the things that can be helpful, you know, this might be the time to have a fatty coffee. I’m not normally a huge proponent of fatty coffees, but this can sometimes be a way to stretch out that that opportunity of not eating first thing in the morning, maybe you’re having some MCT oil in your tea, maybe you’re having some msi2 or oil in your coffee if you tolerate dairy. And I know that a lot of my patients are not very dairy tolerant.
So if you are indeed tolerant of dairy, perhaps having a small amount of full fat cream or you know, maybe having some high quality butter in your coffee can help kind of stretch you through until you have that first meal. But I think the one thing when it comes down to blood sugar dysregulation and feeling hungry is supporting our patients and helping them understand that this is usually temporary. It’s usually a sign of wanting to make sure that we get that blood sugar stabilized. This is something that I think can be improved upon fairly quickly, especially with a great deal of coaching, to help them understand that if you are hungry, we are not suggesting not to eat. However, the way to kind of troubleshoot that is to say, okay, what did I eat during my last meal? Maybe that next meal I need to give myself one more ounce of protein. Maybe I need to have a larger portion of healthy fats. That’s a good starting point before we start really opening up a feeding or a fasting window or even entertaining that possibility. I think for many, many of my female patients, there’s a great deal of fear around not eating. We’re so conditioned our patients to believe that what they need to do is do the eating around the clock. So if we’re suddenly suggesting no, now we want you to eat two or three times a day, that can be very frightening. So a great deal of coaching and support to help them understand that this may be two, three weeks before you get to a point where you’re not feeling that you know, that hunger feeling. And let me be clear, we’ve also conditioned our patients to think of hunger as a bad thing. I think, you know, that digestive fire, that hunger is not intrinsically a bad thing. But I find for a lot of people when they say they’re hungry, they’re actually dehydrated. So making sure that you’re consuming enough high quality water and by that I mean filtered water during the day having some electrolytes, the recognition that if it’s if it’s true hunger, I mean, there are these counter regulatory mechanisms that over time, as you begin fasting, will help suppress those hunger cues. So, you know, norepinephrine, some of these counter regulatory hormones will start being secreted in greater amounts. It can help with that hunger and satiety, you know, concerns that people have. But making sure you’re really well hydrated, I think is also beneficial as a number one, hitting those protein macros and making sure you’re eating of healthy fats. Number two, a little bit of mindset work. And then I would say number three is understanding that our bodies are a really good job with these kind of regulatory hormones to help suppress hunger in a way that we can go along in our mornings and not be so so food focused, but also understanding that that’s there for a reason. And so we can go about our morning, maybe go a little bit longer without eating and then slowly working our way up to whatever window, you know, ourselves, our provider and our patient have decided that we’re going to work towards.
Felice Gersh, MD
You’ve touched on a few things. I want to go back and touch on some more, like breakfast or dinner. So what about individual meals? Does it matter which time of day you eat your biggest meal? Is breakfast important or not important? It seems to be a controversy that’s ongoing. And you know how late at night can you eat and then can you then fast until the end of the day, the next day. So maybe just talk about the rhythms you mentioned about the time that you eat, not just don’t eat so much so often, but when you eat, does it matter.
Cynthia Thurlow, NP
Now? It really does. And so if we look at the chronobiology or the circadian rhythms in the body and we know that cortisol is this beneficial hormone, it’s not all that I just like insulin’s not all bad helping people understand that we are more insulin sensitive, which means we can get away with a bit more food earlier in the day than later in the day. So let me explain. We get up in the morning and maybe we get up at 7:00 in the morning. We nine or 10 a.m., we choose to break our fast and you can break your fast at any time during the day. Does not per se have to be breakfast food. It does not have to be before 9:00 in the morning if you choose to break your fast. I always say this is a good opportunity to, you know, they jokingly talk about how we want to eat like a king in the morning, but that might be the perfect time to have a larger meal of the day when you can get away with a bit more discretionary carbohydrates, protein and healthy fats because you have the whole rest of the day to work that meal off, whether with physical activity or just, you know, they call it needs this non exercise induced thermogenesis. So helping people understand that when we’re going about our day, we are more insulin sensitive earlier during the day. So I always say when it’s light outside, that’s the time to eat. When it’s dark outside, that’s the time to eat less or not to eat at all. So maybe you break your fast at 10 a.m., maybe you have a, you know, maybe have dinner at five or 6:00 at night. I do like my patients to finish their their feeding window 2 to 3 hours before bed. So it’s really reengineering. When do you go to bed? If you go to bed at ten, then you want to make sure that you’ve had your last bit of food by 7:00 and helping people understand obviously easier during the spring and summer when we have longer days, longer days of daylight. But understanding as the day is going on, we become less insulin sensitive. In fact, I wear a continuous glucose monitor and I can watch and trend the data throughout my day. I can see if I choose to have squash at noon. It’s going to be metabolize a little differently than if I’m having squash at 7:00 at night. That’s me personally. With that being said, that kind of hormone to cortisol is melatonin. And so melatonin is the sleep hormone. It’s also a master antioxidant in the body and helping people understand that, you know, if you decide to eat as an example at 9:00 at night and that happens, you go out, you’re on vacation and you’re wondering why you have such a rotten night of sleep. And it has a lot to do with the fact that, you know, we talked about cortisol. There’s this ebb and flow throughout the day, highest in the morning, ebbs and flows in the afternoon and then lowest in the evening, which is helping stimulate secretion of melatonin among a few other mechanisms, helping people understand that melatonin is the sleep hormone. But if you eat at 9:00 at night, you’re going to suppress melatonin. Your body is going to increase cortisol to help process this bolus of food. And that in and of itself can impact your sleep quality. We know that we have melatonin clocks throughout our body, but we actually have them in our digestive organs as well. And so if you’re eating this large meal at 9:00 at night and maybe you’re having alcohol and maybe you had more carbohydrate than you normally do, and then you try to go to bed 2 hours later and you’re having reflux and you just don’t feel good. Has a great deal to do with the fact that you’re giving your body competing interests in order to be able to. You’re telling body it’s time to go to bed and your body’s saying, Hey, I’m still digesting this large bolus of food. I’m confused. I’m not sure what to be doing. If you add an alcohol on top of that, it can actually impact your REM and your deep sleep quality. So helping people understand that the ideal way to eat is to eat, you know, your largest meal earlier in the day, which is much more aligned with our our chronobiology, our circadian biology. And to close down your feeding window, 2 to 3 hours before bed. Now, I know a lot of women will say, well, you know, I don’t get to see my kids or my husband until seven or 8:00 at night. I get it. Save the bigger meal for earlier in the day and either have a small meal with your family or a small meal with your significant other spouse. Or, you know, you can identify to your family members that you are not eating at seven or 8:00 at night. I mean, my family is completely accustomed to this on some days. If I’ve needed to close my feeding window earlier, that’s okay, too. You know, being your own best advocate, but helping people understand that if we are eating aligned with our circadian biology, we eat when it’s light outside. We don’t eat when it’s dark outside. Ideally. And we want to really focus in on having our largest meal to date earlier in the day and our smaller meal that kind of, you know, closes our feeding window later in the day. Those can have some huge net benefits, not just on metabolic health, but also our insulin sensitivity, our blood sugar regulation, how we sleep, I think is very, very important. And we know that, you know, on top of the sleep, peace and then interruption. That can happen if we’re eating too close to bedtime. We know that if you’re not getting enough sleep, that in and of itself, statistically and based on research, will impact not only the following days blood sugar, but also your leptin and ghrelin. So these key appetite and satiety hormones can all be dysregulated in response to late night eating, not getting enough sleep, and definitely can set you up for, you know, not making those great choices the following day.
Felice Gersh, MD
Now, you’ve talked a lot about insulin and you’ve mentioned inflammation. Now you were the exception, you know, like the 20% lean PCOS, but the majority are trying to lose weight. So how does the intermittent fasting translate into weight loss or is it mostly just about which is not a little thing about improving metabolic health? How does it help weight loss if it does at all?
Cynthia Thurlow, NP
Yeah. So this is a great question. And I would say 99% of the women that come to me that want to be coached about metabolic health and intermittent fasting have a desire to lose weight. And let me be clear, this is a key benefit. It’s usually the one that people are most attracted to. They want to change body composition. They want to lose weight. That is a byproduct of a completely reasonable desire. And I realized, as I was saying this, that it was something I didn’t talk about is one of the key benefits. Because I always say people come to intermittent fasting for those benefits, but they stay for all of the rest. So if you are a woman that is under the age of 35 and you have PCOS or you’re already insulin resistant, you have quite a bit of weight to lose. I think intermittent fasting is a great strategy with the caveat that we want to be conscientious of the fact that you are still in your peak fertile years and your body is exquisitely attuned to what goes on in our environment, whether it’s core medic stress, which is beneficial stress, whether it is actual stress, the nutritional cues that they’re receiving, our sleep quality, do we exercise, etc.. So I think that when we’re talking about younger women and even women in perimenopause, I do think intermittent fasting absolutely plays a role. I think we have to be careful with lean women that they are not over fasting. And that doesn’t mean, you know, a woman under the 35 is already in a healthy weight. Does not need to be fasting routinely. Maybe you’re doing it once or twice a week because my concern is always over losing muscle mass and we can talk more about that. But when we’re talking about an obese woman that has PCOS, it’s either still in there fertile, kind of fertile years where they’re in perimenopause.
It’s helping them understand there’s times in our menstrual cycle and we can get away with a bit more intermittent fasting, rigorous exercise, lower carbohydrate diets. And that’s during the follicular phase. And this is really when estrogen predominates. And estrogen I always think of estrogen as this incredible super power hormone. And we can get away with a lot more stress on our bodies at this time and in our cycle. And so understanding where you are in your cycle, so you know from the day that you start bleeding depending on how you’re feeling up until relatively and I’m oversimplifying things. Dr. Gersh relatively up until ovulation. This is when the follicular phase really predominates and when women will oftentimes have higher levels of estrogen, they can get away with a bit more intermittent fasting. And so I think if you’re dealing with someone that wants to change body composition, wants to lose weight, a degree of intermittent fasting every day for someone that’s obese or overweight, I think just completely acceptable.Again, being mindful of the fact that our bodies are exquisitely attuned to cues in the environment. So we want to make sure that in that feeding window we are getting enough protein, we are getting sufficient amounts of healthy fats, we’re eating non-starchy vegetables, we’re getting high quality sleep. And then, you know, after ovulation and again with PCOS, that may not be occurring on schedule, that may you may have this very prolonged luteal phase. But helping women understand this is when I generally recommend no more than, you know, 12 to 13 hours, ideally when this 5 to 7 day range prior to your menstrual cycle again if you are a typical PCOS are like I know I was I just had these really long cycles. It became very challenging. But when progesterone predominates, this is what I generally recommend a little less stress in the the luteal phase of our cycle and obviously depending on the situation and the person, I have some PCOS patients who still have fairly predictable 40 day cycles. I have some PCOS patients who have very unpredictable cycles. It is very, very bio individual, but understanding where you are in your cycle has a large component or contributor to fasting success. So you can do fasting throughout your cycle. You just have to be conscientious about where you are. And again, I know not every PCOS patient is 100% aware of where they are. Many of you I know I certainly suffer from this as well. Although my cycles became more regular the older I got, that was something that became particularly challenging. But women being observational of their where they are in their cycle. Number two, managing their stress. So obviously more impactful for older women, women that are 45 and up, we become less stress resilient, you know, especially as our ovaries are. You know, I always remind people that unlike sperm that replenishes every three days, our ovaries are as old as we are. So as our ovaries are kind of wearing, their lifespan is kind of waning, understanding that we become a bit less stress resilient. This is when adrenal support, managing stress becomes so important, not over exercising, not ever restricting of food, because I can see that side of things as well. But I think that the key thing is managing lifestyle. So that we can integrate intermittent fasting depending on where we are in life stage. And it’s certainly something that I become known for is really embracing where we are in our cycle. This is something I did not learn even as a clinician really embracing where we are in our cycle so that we can maximize our quality of life and those health care outcomes.
But I would say the other thing, Dr. Gersh, that I think is so helpful for women is, you know, using a glucometer, getting a sense of what is your response or continuous glucose monitor. And certainly if you are already insulin resistant or diabetic, you know, these are things that can be covered by insurance. But helping women understand what is your personalized response to certain foods as an example, you can be insulin sensitive and there might be certain foods like for me, I love plantains, they don’t like me. It doesn’t matter how I eat them, they spike my blood sugar quite significantly, not just a little bit a lot. But I teach women to understand that when you have a meal, we don’t want to see your blood sugar go up by more than 25 points or so, because that may be that you put your macros together in the wrong way. So let me give you an example. Let’s say your blood sugar before you start eating is 85. If your blood sugar goes to 150, it can be a sign that you put your macros, your protein found carbohydrates might be too much carbohydrate, too little protein, wrong types of fats, helping women understand that there is a way to navigate nutritional choices. There’s a way to determine, you know, what’s the net impact on your sleep quality if you’re not getting a good night’s sleep. And certainly the research suggests that even less than 6 hours a night of sleep can disrupt your blood sugar regulation by up to 40% the following day. Not to mention that appetite and satiety hormones helping people understand the right types of exercise. So it doesn’t mean, as a 45 year old woman going out and, you know, slogging ten miles out every day and really like raising your forties all understand there is a role for restorative exercise, there’s a role for weight training, all of which can help with insulin sensitivity and then the other piece is just getting really, you know, as I always get very granular about the macronutrient piece, really understanding how our our nutritional choices can impact our blood sugar regulation. And these, in turn, can be helpful for weight loss. So that continuous glucose monitor, that glucometer can help raise awareness of, you know, what is what is an issue for you. Like it could be a specific type of carbohydrate. It could be, you know, is your blood sugar is not as well-controlled. If you don’t eat a certain threshold of protein or you’re not eating a lot of those brightly pigmented fruits and vegetables. And I am a huge fan of, you know, eating the rainbow. I think that that’s so important. All the phytonutrients are very beneficial for not just for our health, but our gut microbiome as well. I think they’re the standard vernacular now is that they want people to have 30 varieties of plants over the course of a week, which sounds overwhelming. But then you understand you have so many different components. It could be spices, it could be different types of brightly pigmented fruits or vegetables. It could be herbs. There’s so many different things that you can do to integrate into your diet. They can help with the health of that gut microbiome as well as many other things. But those are the things I typically really focus in on for my obese insulin resistant patients, is the macro piece, helping them understand, you know, their personal response. And then the other thing is something as simple as walking after a meal. We know, you know, 10 to 15 minutes of walking after a meal can be very helpful, really making sure they’re getting high quality sleep. And I don’t know about you, but I can’t tell you how many high functioning women will say to me, well, I can’t I can’t do more than 6 hours a night. And I would say we can do 30 minutes more and then slowly work our way as up to 7 to 8 hours. We know that can be very important, not just for weight loss, but also for reducing inflammation in the body.
Felice Gersh, MD
Yes, really, really important to know your own body. I love the idea of using the continuous glucose monitor. So you see, you know, your own unique responses and how it can change over time. And you mentioned and this is, I think, very important about different phases of the menstrual cycle, the different hormones and their effects. Well, many women would PCOS are put on oral contraceptives, a.k.a the birth control pill. So obviously they don’t have real cycles. They bleed if they have the withdrawal bleed, which some don’t. So have you seen in your practice that that has a negative or a positive impact on the results with intermittent fasting? Do you just say, you know, just do the best you can because you obviously don’t have a phase of of a cycle. You don’t have estrogen and progesterone in any kind of a rhythm. So how do you manipulate if if you do at all, the intermittent fasting component in women on birth control pills?
Cynthia Thurlow, NP
And it’s such a great question. And I that most women that are choosing to take contraceptives, there’s a reason whether it’s they need it for contraception, whether they had really horrifically heavy menstrual cycles at a certain stage. And they just don’t want to go back to that. When many women, quite frankly, like the convenience of knowing that they don’t have to worry about anything, that there is, you know, everything’s humming along. But what I find most interesting is most of the women, when they come to me, they’re very curious. They want to be able to do something proactively. And so there’s a couple of different ways. And Dr. Gersh, you know, this is this is not like scientifically based, but we can we can cycle with the lunar calendar. We can, you know, wait for the full moon. And some women like to be very proactive. And so in their minds, they’re like, the full moon comes and in their mind what they want to do is they know for the next two weeks roughly, that they are going to embrace a little bit more fasting and they’re going to push their workouts. And then, you know, when they get to a different phase in the lunar calendar. So over this 30 day cycle, they have two weeks where they back off and they actually like the variety. They like knowing that there’s going to be a pushing, you know, a time in the cycle where they are going to push a little harder. And then there’s going to be a time in the cycle where they’re going to do more restorative activities. Maybe they’re not doing as long a fasting. I have found for many of these women and there’s probably 20 or 30 that I’ve done this with, they like they like the idea even though they understand intellectually that if they’re on oral contraceptives, that their hormones are kept very low, they have a lot of self-reported improvement in symptoms. And I find this interesting. So it goes to show you there’s a degree of psychosomatic that goes on, but psychologically they feel better and they feel like they’re being more proactive. For many of them, they’re not ready to give up being on oral contraceptives for a variety of different reasons.
And I think part of my role, I think, as a health care provider is just meeting my patients where they are. So for them, you know, they either do seed cycling or they’ll cycle with the lunar calendar or they’ll keep a I tell them keep a symptom journal and, you know, let’s just see how you feel over the course of a month. And then they’re much more attuned to how they feel day to day. Maybe they feel more emotional one day. They feel less emotional the next day. What I find interesting I don’t know if this has been your experience, Dr. Gersh, is that many women, while they’re on the pill, they have more PMS than they do when they’re not on the pill any longer. And so I think for many women, they’ll report significant PMS symptoms and they’ll say to me, you know, do you think it’s because I’m on these synthetic hormones, these non-bio identical hormones? Do you think this is one of the things that might be mitigating my symptoms? And we always said we don’t know. Obviously, it would make sense for that to be the case. So that’s typically how I handle life. Some women that, you know, they want to just do their own thing and they they don’t want to ascribe to any particular cycle, whether it’s a lunar calendar or speed cycling. Others are much more comfortable and open minded. And the ones that are willing to do that, I’ve had self-reported. They feel better. And so I always say there’s no shame or, you know, to me it’s such a benign thing to do that if they feel good while they’re while they’re doing following the lunar calendar, I would say that it’s such a benign way to support your body. And they feel like they’re doing something proactive for themselves.
Felice Gersh, MD
Well, that’s, I think, a pure case of mind body medicine. And I’m a huge a big fan of mind body medicine. Now, if you had your wish come true concerning the optimal time that people would have not eating. So is there I mean, you mentioned start off with maybe 12 hours and you know, you’ve mentioned some people do 6 hours. Is there recognized an optimal amount of time that you should go without eating? And in terms of like from one meal to no eating at all until the next meal. So, you know, 12 hours, 13, 14, 16. And how about between individual meals? Is there any sort of optimal timeframe for that either?
Cynthia Thurlow, NP
Yeah. So let me let me answer the second question first. I think the optimal time in between meals is 4 to 5 hours. You know, the one thing, as I was writing my book about intermittent fasting, I kind of dove into the research around the migrating motor complex. And the way to have that mechanism really magnified in the body is to go 4 to 5 hours. Now, there were probably people listening there saying, that’s not realistic for me. You have to do what works for you. But for me, I think the magical time is 4 to 5 hours. So if you break your fast at 10 a.m., you’re not eating again until two or 3 p.m.. That would be a magical ideal. We’ll put that at the Ivory Tower of time in between meals during the day, in a feeding window. Now, when it comes to time of not eating during a day, as I said earlier, I think that 12 hour window is the bare minimum for everyone, even includes I have teenagers now and so they’re very hungry all the time. And I even say to them, you have to give your body a digestive rest. And so I really think about that 12 hours a minimum when it comes to other feeding and fasting windows. I think that there are obviously benefits of working towards a 6 to 6 hours fast with an eight hour feeding window. If someone has significant weight to lose, if someone is really struggling with breaking through plateaus, this is when I think some of the longer fast can be beneficial. Whether a 24 or a 30 hour fast, there’s something called the 36 zig or 30 hours fasted and then you have a 16 hour feeding. So it’s kind of this alternating fasting feeding schedule.
And I do find that some of the longer fast for plateau busting or weight loss resistance are particularly beneficial. Obviously, I don’t like really long fasts to be done regularly if someone is already thin and lean because of my concerns about the loss of muscle mass and we know sarcopenia is a real issue, especially as we get older, that we want to maintain our muscles so that we maintain our insulin sensitivity. So I think in that context, I would say, you know, the gold standard is a 16 or an 18 hour fasted period of time. I think that’s a great goal to work towards. And then if someone is dealing with is dealing, you know, greater concerns like they have quite a bit of weight to lose, there’s quite a bit of inflammation, oxidative stress and certainly at the basis of PCOS is that depending on the age and stage of a woman, I think there’s a lot of benefit for some of these longer fasts in conjunction with communication with your health care professional to make sure that you’re you’re fully optimized to be able to have success with that. I think those in particular, especially because you get more autophagy, you get more reduction in inflammation, you fast, long enough, you can get, you know, stem cell activation, you can improve, you know, longevity. And so obviously different types of ask for different needs. And that’s always the first question I ask people when they come to me is what are your goals so that we can make sure we tailor the type of fasting that we’re doing based on what you are looking for and what is realistic for you. Now, if you are super thin, 25 year old woman and you’re doing long fasts all the time, and that’s a pretty darn good way to create some havoc in the body. You know, I always talk about her, me, sis, or beneficial stress in the right amount at the right time. My really thin young women I’m not a fan of really long, fast and certainly less is more for them. But if you’re obese, overweight, you have PCOS, you usually have a bit more to play with. And that’s where some of those, you know, strategies for a longer, fast can be very, very impactful.
Felice Gersh, MD
I go back to what you began with at the beginning, which was for the most typical scenario. Don’t try to push it too fast, too hard, right? Because it just takes time. I know I learned that the hard way in my old practice trying to initiate fasting regimens, that you’ve got to take it slowly, you know, and help people adjust because otherwise they throw their hands up and say, I can’t do this. I’m too hungry all the time. And and they start doing bingeing. We don’t want that. So take it slow and steady. You know, that’s like this tortoise will win the race, right? So that you’ll get there. Now, you clearly are a world class expert in this topic and everyone who is new to this wants to learn more. And that’s a lot of people out there. So I see you have the book behind you, which is fantastic. So maybe tell about your what you’ve written and how they can follow you and learn more about this really important topic.
Cynthia Thurlow, NP
Thank you. It is something I’m particularly passionate about because it runs contrary to everything I learned as a clinician and I feel like intermittent fasting is an important strategy that women can utilize throughout their lifetime. So my book is written by Woman for Women talking about intermittent fasting, talking about the hormones around fasting, talking about how to fast for a younger woman, selling your peak, fertile years, perimenopause and menopause. I have all the science behind it. Lots of research, which I think is super important and then a lot of clinical experience. Because when my second TEDx talk went viral four years ago, there was suddenly a lot of people who wanted me to coach them through intermittent fasting. And so at the basis of the book is my program is 45, so it’s a 45 day program to get women from not fasting to fasting successfully with a lot of support. You know, there’s a day to day program. There’s lots of recipes in the book that are nutrient dense and obviously focused on, you know, healthy, healthy fats and protein and lots of healthy carbohydrates and vegetables and healthy fruits. And when it comes to connecting with me outside of the summit, I have an amazing podcast called the Everyday Wellness Podcast that Dr. Gersh has been an expert on several times. She’s a fan favorite fact. I love sharing with her that over the past four, my number one downloaded podcast is the second podcast we did together. So your content really resonates with my community. I’m active on Twitter. Be forewarned, I could be a little snarky. I’m on Instagram as well as YouTube, and I would love for you to reach out and say hello.
Felice Gersh, MD
Well, I think everyone is going to be doing that. You’re going to get a lot of likes. So thank you so much, Cynthia. This has been really eye opening for, I’m sure, so many of the women with PCOS who were taught. Unfortunately, like many of us were in our schooling, that you should keep your blood sugar up by eating every 2 hours. So let’s put that to rest. Let’s bury that forever and embrace this new but not really new in that humans always did this before we came up with the other ridiculous notion that you have to keep eating around the clock. So thank you for introducing everyone to this critically important topic for health optimization, intermittent fasting and I look forward to working with you again many times in the future. So thanks again for coming on my show.
Cynthia Thurlow, NP
Thank you so much. It’s been a pleasure and an honor.