Intermittent Fasting, Insulin Resistance and Breast Cancer with Cynthia Thurlow

Cynthia Thurlow discusses how intermittent fasting and metabolic health relate to breast cancer risk. Walk 10-15 minutes after meals, eat within a 12-hour window, get 30g protein per meal, and aim for fasting glucose around 70-85 mg/dL. She cautions against fasting for pregnant women, children, and people with eating disorders.
Questions this video answers
October 23, 2023.
About 70–85 mg/dL (fasted).
She cites a fasting insulin ideally between ~2–5 (units quoted in the conversation).
About 14 days.
She recommends not seeing more than ~25 mg/dL increase after a meal (as a general goal).
Chapters
Welcome back to the Keeping your breast podcast. I'm your host, Dr. Jen Simmons, and I am super excited for my friend and extremely accomplished clinician to be joining me today. Today I have Cynthia Thurlow. She has an amazing story of transformation from the conventional medical world, where I started as well, to where she is today. And she. She wrote a book about transformation. She embodies transformation. And I'm so excited for her to share her story with you and the amazing contributions that she's making to the world. So, Cynthia Thurlow, welcome.
Thank you so much. I've really been looking forward to connecting with you and your community.
Oh, thank you. And my community needs you because you. You know, when we talk about breast cancer and we think of it in a silo, it's really not, because I've said repeatedly and you've said repeatedly, breast cancer is a metabolic disease, and it is the result of metabolism gone wrong over a long period of time. This isn't something that happened overnight. And we're really living in a society of metabolic derangement. And I know you talk about that all the time, so can you start to unpack? Well, first, I would love you to share your story because I think that so many people will identify with your struggle and what you went through and what you felt.
Yeah. So I am a traditional allopathic trained nurse practitioner. I spent all of my years in clinical cardiology and critical care medicine. And prior to that, I was an ER nurse in inner city Baltimore. And I'm a bit of an adrenaline junkie. So for me, I kind of loved where the action was, you know, the most critically sick patients. And, you know, I did that for a while, and then I had children and suddenly I wanted a little less excitement in my life. I wanted more predictable hours. So I kind of transitioned into clinical cardiology. So I was in the office, very autonomous, seeing very sick people still, but making a lot of determinations about whether they were going to surgery or whether we needed to be very aggressive about lifestyle management or medic. And, you know, my oldest son developed life threatening food allergies. And I read a book called the Unhealthy Truth by Robin o'. Brien. And I always like to give credit where credit is due, that we have these books that come to us and we're ready for the message. And it turned everything I knew on its head. All of a sudden, I started thinking differently about nutrition. I started thinking very differently about pharmaceutical industry. I started thinking very differently about the way I practiced, even though I was practicing evidence Based medicine. I started to think very differently about all of this.
And over time, when was this, like, give me, give me a period of time.
This was 10 years ago. So I had been an NP for almost 10 years at that point. And I think having a child that I suddenly had to worry about if we went to someone's house for dinner and I had to carry an EpiPen, and the resounding words that the allergist said to me were, carry an EpiPen and pray. Now, I don't know about anyone listening, but when you have a two year old and I had a newborn and a two year old and all of a sudden I had all these fears and concerns about food, it's terrifying. It was terrifying. And he was this healthy kid. He just had terrible eczema, which I had no idea what that was derived from at that point. I just thought, oh, it's, you know, he's got an autoimmune thing. It's gut health. I mean, that's as much as I thought about it.
But really, at that time, was there really any connection between autoimmunity and eczema? Because I, I had a kid around that time and he was just permanently covered with a rash. And they would tell me, like, yeah, that's just him.
Yeah, yeah. Well, what's interesting is, number two, kiddo, none of the same health issues. And so it wasn't until I, a female physician who was doing, I mean, cutting edge integrative medicine, and we had a conversation and she said, cynthia, you realize why your son is eczema? And I was like, no. And then we had this whole conversation and it was like as if someone had just burst my brain. I was like, wait a minute. I, you know, I trained at this, like, leading university and medical center. We never talked about these things and making this complex interrelationship between lifestyle and autoimmunity and gut health and, you know, the constellation of things that come out of that. And so that was probably the first thing that happened for me, was I started thinking very differently. I started getting very passionate about nutrition in particular. We'd always eaten healthy. Let me be clear. It wasn't like I was eating a standard American diet, but I mean, I was looking at every ingredient label and started looking. My husband thought I had lost my mind. It was like seed oils and high fructose corn syrup. All these things that we just thought nothing of. We thought it was completely benign. And then probably a few years later, as I was getting increasingly more restless in this, this nurse Practitioner role in cardiology. I myself kind of fell into the hole of perimenopause. And so for any woman listening, if you've been through that, you can imagine as a clinician, if I didn't have the answers and all I was being offered were synthetic hormones, an iud, and ablation or hysterectomy to solve my symptoms, which I said was woefully inadequate and unacceptable. I went down another kind of rabbit hole trying to figure out how to deal with weight loss resistance, how to deal with escalating anxiety and poor sleep. And I kind of came to intermittent fasting. And so that, for me, started as the experiment at the end of one to see a strategy that maybe might make me feel a whole lot better. And I didn't lose the weight instantaneously. I always like to be very upfront about that. That required several other things that I had to change, but that started this whole journey down. Intermittent fasting and talking to my patients and talking to every physician that was willing to listen to me said, I think we're really onto something. There's this doctor, Dr. Jason Fung. He's a nephrologist. He's getting really good data and really good research out of working with this patient population. And I always like to give credit for credit is due. But I always. And I've said to Jason, you know, thank you for allowing me to have another clinician to look up to who validated using the strategy and using it in a way that was very therapeutic.
So that's where you first learned about intermittent fasting?
Yes. Jason Fong.
Amazing.
Yeah. Jason Fong. So. So, yeah, it started as the end of one, and then it started kind of bleeding into all the work I was doing. And then I got really fed up six years ago, and actually seven years ago now, and left clinical cardiology. I took this massive leap of faith with no business plan, no business experience, and said, I think I can make a bigger impact by leaving conventional allopathic medicine. And my husband thought I had lost my mind. This is this reoccurring theme. I know all about that. Yes. And I said, I can make a bigger impact not being in a box. I have so much more to offer. I know I can make a bigger impact. And then it just started to steamroll. Women came to me who were dealing with the same issues I had been dealing with, who were frustrated, felt like they were their concerns weren't being taken seriously. They were told things like, weight gain is a normal function of aging. This is just the Way things are, you're not meant to have good sleep. You're not meant to be able to manage your stress. Here's an antidepressant. Oh, we've got really heavy periods. Let's put you on more synthetic hormones. Let's just take out your uterus because you're done having children.
Yeah.
And so now I feel like we have this amazing community of women who believe in lifestyle as medicine and a community of individuals, healthcare practitioners as well, who believe in this, too. And I always tell people I really do believe in traditional allopathic medicine. If you have an emergency or an urgent situation, I benefited from it four years ago when I almost died from a ruptured appendix. But for most other things, we really do a crummy job. We don't manage chronic disease well. We don't do a great job with prevention. And now I get to, in many ways, impact more lives and have a greater voice and the ability to, you know, change the trajectory of where things are going. And that is really humbling and also incredibly powerful. So to your point, I wrote a book, I had a talk that went viral in 2019 that kind of got the snowball going. And so intermittent fasting in women has really become something that I'm well known for. But what I would say what preceded any of that is metabolic health. I mean, obviously, being passionate about cardiology and being passionate about lifestyle medicine, you can't not focus in on the lifestyle piece. That is what's most important, and that is what we oftentimes don't get compensated for. And that's oftentimes what gets swept under the rug. In lieu of managing quote, unquote symptoms with pharmaceuticals and little to no education about the value of sleep and stress and exercise and nutrition, which really should be the cornerstone. That should be the stepping point before we even think about managing lifestyle diseases. We should be using lifestyle medicine first, and then if it doesn't work, it isn't effective enough. The consideration to adding in pharmaceuticals, but not starting with frontline therapy. And that's what I. Unfortunately, I think many, many of our colleagues are coming around to this and embracing this. But there are just as many that say things like telling your patient to wear a continuous glucose monitor is dangerous. I won't tell you who on social media, but this individual tried to have a full spat with me on Instagram telling me I was dangerous, because I.
Get told that all the time, too. Yes, Cynthia, I consider that a compliment at this point. Right. Like, I. I tell women not to get mammograms because mammograms deliver harmful radiation. And the more mammograms you have, the more. The more likely you are to get breast cancer. I mean, we are literally creating our own customers. And yet radiologists all the time on Instagram tell me that I'm dangerous and killing people, but I'm not the one delivering radiation. How am I killing people?
Exactly. But. But I think this really speaks to the need for an understanding that how we trained in the 1990s and the 2000s, which is when I was in my training, things have evolved. If you're still practicing 1997 medicine, there's a problem. Because I know that I was trained even as a nurse and a nurse practitioner, that it was my responsibility to remain current and to question constantly like I was trained. That was something that was specific to a Hopkins nurse, that we were taught it was imperative that we question everything. And I've never forgotten that my parents were the same way. That's a whole separate conversation, but questioning and thinking about things from a level of maybe I didn't know better, but now I do. And that's what I think is so important. Admitting that in 1997 I didn't know any better, but now I do, and I want more for my patients and clients. And I know you and I share that, and so many of our peers do as well, that we are designed to evolve, shift, and change throughout our lifetime. If you're not doing that, then you're doing it wrong.
Yeah, I couldn't agree more. You did say that when you started to learn about this and started to do intermittent fasting, and you said it started to bleed into your practice. So I'm curious about the reception, both on the patient side and on your colleague side.
Well, I can tell you that my physician colleagues, most of which. It's cardiology, most of them are male, they would say, this is rnp. It's so cute. She thinks nutrition's important. Honest to God, most of them, that was the prevailing idea. However, a lot of my colleagues who are closer in age to me were like, we really see a lot of value in what you're doing. So they were very supportive. Patience. Yeah. I mean, I thought that was always very encouraging. And actually, some of them will still refer people to me. They're like, go follow Cynthia and read her book and do all these things. What I thought was really interesting, though, is how many of my patients, because I was always trying to find an angle. How can I motivate them to take better care of Themselves, you know, they're, you know, at the time that I left clinical cardiology, I was still in my 40s and they might be 10 years younger than me. And I would say, how old are your children? Oh, they're three and six. I want to make sure that you are vital, healthy, able to keep up with them, send them off to college, send them off to grad school, whatever it is, see them get married. I really would love for you to take a walk after you eat, or I would really love for you to eat a little more protein, a little less carbohydrate, or maybe even something as controversial as recommending they stop smoking entirely because you and I both know how important that is. And 90% of them would say, I love you as my, as my, as my provider, I respect you, but I'm not going to change what I'm doing. I'm not going to exercise, I'm not going to change my diet, I'm not going to stop smoking. So just give me the higher anti hypertensive, give me the lipid lowering agent, adjust my insulin. And so we have literally conditioned our patients to ask for more medication in many instances versus change their lifestyles. And that to me was tragic. Now the, the 10, maybe I'm being generous, maybe 7.5%, 5% that were willing to change. That was exciting, that lit me up. I was like, this is actually what I enjoy doing is I'll have them come back and we'll, I'll see you every two weeks and we'll talk for 20 minutes and I'll give you some recommendations, I'll recommend books, I'll give you resources. That was exciting. Those people that came off their antihypertensive, came off their lipid lowering agents and always making sure I kind of looped them in with their doctors because everyone's like, what are you doing? You know, why is this patient now going from three anti hypertensives down to two, down to one, down to none? And I was like, because they're no.
Longer insulin resistant for people who don't necessarily understand that. And I do want to get into why insulin is so important and why the medical system is not measuring it.
Yeah, right.
So can you talk a little bit about the glucose and insulin relationship? Because it's, it's especially important in the cancer population.
Yeah, I think most people have probably heard of glucose. And so this is a hormone in our bodies that is designed to be kept within a narrow therapeutic.
Glucose isn't. Glucose is our blood sugar.
Yeah, sorry, that's okay, talking about, we're talking about glucose. And so in response to food, this is probably the easiest way to explain this. In response to the food we choose to eat, whether it's protein, carbohydrates, fats, in response to the food we eat, our body has changed, have fluctuations in our blood sugar. Now, to give you an example, the macronutrient that has the most negligible impact on our blood sugar is fat. So if you have avocado, if you have MCT oil, if you have butter, very negligible impact on your blood sugar. However, things like protein kind of in the middle and protein's not bad. I want to be clear about that. Whether it's steak or chicken or tempeh or whatever variety of proteins you enjoy, carbohydrates are different. However, carbohydrates by themselves have the most net impact on our blood sugar. And so when I talk to patients about whether it's a piece of fruit versus rice versus processed carbohydrates like bread and pasta, there's a long continuum. Carbohydrates are not intrinsically bad, but the processed carbohydrates are the things that get us into trouble. And why this is relevant is the average American right now consumes food or beverages anywhere from 10 to 12 times a day. Now, that may not sound like a lot, but it's with the understanding that if we are eating all day long versus having three meals a day or two meals a day, every time we eat this meal, whether it's a steak with broccoli or we sit down and eat a massive bowl of pasta with no protein with it, your body has to, has to kind of address the food that you've consumed and it has to manage the increase or the, they call it glucose spikes. That's now kind of this, this kind of popular vernacular. Your blood sugar response, which is glucose, blood glucose and, and blood sugar are the same thing. Your glucose response. What we don't want is to be eating all day long and keeping our blood sugar elevated. When our blood sugar remains elevated, our body has a hormone that's insulin. So we're, we're trying to, to keep our blood sugar, our blood glucose, in a very narrow window. You know, what happens is we eat a meal, our blood sugar goes up, our body secretes insulin to pull it from the bloodstream into the cells. That's ideally how it's designed to work. But if we are eating 10, 12 times a day, both sugar, sweetened beverages and food, wrong types of food, we're going to keep that blood glucose high. And over time, we can get to a point where we are no longer into a position where our bodies can effectively move that glucose out of the bloodstream into the cells.
What's the problem with elevated glucose? Like, why is that a big deal?
Yeah, so it can damage cells. We know that. It can damage our retinal cells, it can damage our kidney cells, it can damage our heart, it creates inflammation, creates oxidative stress. It can make our platelets, which are these cells in the blood that kind of move and help with blood clotting. It can make things sticky. And over time, if we have elevated blood sugar that's not being properly kept within that narrow index or that narrow parameter, it goes on to develop, it goes on to damage cells. And most importantly, if our blood sugar remains high and our insulin can't bring it down, effectively our body. It's almost like I use the analogy of a gas tank. So we. My father's like this. My dad never lets his gas tank go to empty. He's always topping it off. You know, he gets half a tank, he tops it off. So think about the fact that if you're constantly eating, your body's never having an opportunity to get in and access stored fat as a fuel source. So our bodies can use multiple different fuel substrates. It can use glucose, it can use fat, it can use ketones. Most of us here in the United States, our bodies are so poorly metabolically flexible, meaning that our bodies can't use stored fat as a fuel source is where people became weight loss resistant, they become metabolically unhealthy, they become insulin resistant, diabetic, etc. Their bodies are just skimming the fuel off the surface because they're never allowing their body to have an opportunity to go to empty. Use some of the stored fats as a fuel source, free them up, and utilize them as stored fuel. So when we're talking about the importance of insulin, insulin gets a real, really bad rap. Insulin is a very important hormone in the hormone hierarchy. It's like oxytocin, insulin, cortisol, helping people understand. Also, if you're dealing with chronic stress, you know, the last three and a half years, my goodness, I mean, there's been no one that hasn't experienced more stress than usual, but helping people understand that if you're chronically stressed, cortisol goes up, blood glucose goes up, insulin goes up. I mean, it becomes this cascade of understanding this very complex interrelationship that our bodies are designed to adapt to stress, but not chronic stress. Our bodies are designed to adapt to what we eat, but not if we are not eating the right types of foods. We're eating too frequently. And what I have seen over the past 25 years is that we have individuals that are increasing, less metabolically healthy. We're seeing escalating rates of metabolic disease. Cancer is one of them. We're seeing a lot of people who are. The norm is now to not be healthy. The norm is to be obese, overweight, diabetic, hypertensive, cardiovascular disease, neurocognitive disorders, cancer. And a lot of it has a great deal to do with. It is the way that we live our lives. You know, it's the chronic stress, the poor sleep, the poor dietary intake, the meal frequency. And so when I think about glucose and I think about insulin, it's helping people understand these are not bad substances.
These are actually, you can't power your body without glucose.
Right.
Glucose is not bad.
Right. And so I say the same thing about insulin because people automatically say, oh, insulin's all bad. And I'm like, no, actually insulin's a very important hormone for a variety of reasons. There's a lot of metabolic benefit from hormone, from these being optimized. But when I think about the poor understanding of. As an example, when I finished my nurse practitioner program in the early 2000s, a hemoglobin A1c was a big deal. That was new. You know, hemoglobin A1C gives you a 90 day snapshot of glucose control. Right. I don't even look at hemoglobin A1Cs. I don't even take them into account because we have better ways to measure metabolic flexibility. And what many healthcare practitioners don't think about is they'll, they'll measure glucose and they'll say, oh, it's 102. That's not bad. No, that's actually not good. I usually say 70 to 85 is what we're aiming for. And we know a blood glucose in a fast.
Now is that in a fasted state.
That'S what you're looking for, we're aiming for. But if your blood glucose every day that you get up is 95, guess what? You were at 30% greater likelihood of going on to develop diabetes. Yeah, and that's, you know, that's current research. So what I actually like to do is to look at a fasting insulin because it typically precedes by five or ten years the people who are at greatest risk for metabolic disease. And so a fasting insulin, you know, ideally between 2-5mg per deciliter is really like where I like to see things. But what I see is women will say to me, my fasting blood sugar is 102, my A1C is normal, all my other labs are normal, my thyroid's fine, I don't know why. I'm weight loss resistant. And we draw a fasting insulin and they're fasting insulin 16 and they're a little pre hypertensive and their lipids are a little off. And so we're starting to already see some of these signs. Maybe they've got some truncal obesity. So they have some obesity around their abdomens and really starting to see these kind of pre insulin resistant signs where they're really right there. And this is the time we have the ability to intervene. And so I jokingly say, if you're not drawing a fasting insulin on your patient, the question should be why? Because it's inexpensive, it's covered by insurance. There's a company I have no affiliation with, it's called own your labs. And I think it's like $12. I would say don't get a cup of, don't get a Starbucks coffee.
Don't get two Starbucks coffees and get.
Go get a fasting.
And yeah, such a thing to look at. But I think part of the problem is that people have their fasting insulin drawn and they bring it to their doctor and their doctor has no idea what it means.
But wouldn't. But wouldn't you think, like when patients brought things to me and I remember at the very beginning, like I ran a heart failure clinic. Can you imagine? As a new nurse practitioner, I ran a heart failure clinic. Isn't that funny? I think about this now. I'm like, that was very. That was a big leap of faith. I had a lot of supervision.
You did say that you were, what did you call it? A something junkie, an adrenaline junkie. You were an adrenaline junkie, you know, running a heart failure clinic. I mean, these people are really teetering on the edge.
Yes, they're very sick. And this is back when Natural Core, if you remember that drug, I mean that was like the heyday of Natural core and pro BNPs and all these crazy tests we used to run. I had a patient, he was probably one of my very first patients, and he said to me, cynthia, I want you to look at these three supplements. Do you know, coming out of just finishing school, I was like, what? Anytime a patient brought something up that I didn't Know, I always went and read about it, and I still do that. Like, people will bring things up in conversation. I'm like, oh, I need to go check that out. So that curiosity of maybe I don't know at all is something that all of us should embrace.
And so I think that the medical establishment has this kind of pervasive fear of what they don't know. Yes. And they. They do become stagn with where they finished. So you said, you know, if we are still practicing 1997 medicine today, there's a problem. But we have generations of physicians that are practicing their generation of medicine, and some of them are considered the top of their field. I mean, I remember I have a friend whose son has ankylosing spondylitis, and when he was diagnosed, this is an awful, awful, awful autoimmune arthritis. And when he was diagnosed, I said to his parents, like, this is autoimmune. It's diet. It's his diet that's doing this. And I mean, there. There can be other things. You know, there can be triggers like viruses and mold, but it's. It's the. The autoimmune triad always involves something coming in through the gut. And they went to go see the head guy at MGH at Mass General Hospital, and they told him what I said, and he called me a quack.
Right.
And said, diet has nothing to do with it. This is at MGH. And I'm not saying this. This didn't happen like 10 years ago. This just happened two years ago that he called me a quack.
Yeah.
Right. So I think that there is so much, at least even when I was training, which admittedly was a long time ago, I don't think the philosophy has changed in that they tell you that if you didn't learn it in. In medical school, it's either not true or not important. Maybe both.
Yeah.
And I think that, that, that still exists today. And so all the time, I have cancer patients who bring the protocols that I give them into, into their medical oncologist who says, stop taking all that crap and won't even take the time to figure out what it is. Like, half of the stuff are sensitizers.
Yeah. Well, and it's interesting, I think, Jen, because I'm a nurse and a nurse practitioner, I have always felt like I had to go above and beyond all the time because I was not an MD or a DO And I think especially for, you know, advanced practice nurses, I think we've always felt like we have to be like, 10 steps out, like, I would jokingly tell people the stuff that the NPS did in our. Because we had an MP service within this cardiology group. I said, we always went 10 steps beyond our peers because we had to. And so I think for. For me, I've always had this natural curiosity. And I would say, you know, I. I would like, listen to a lecture. I'm like, wow. Like, I had a really amazing vascular surgeon. I remember I was listening to Grand Rounds. This is like 2001, a long time ago. And I was still. I was like a newbie nurse practitioner. And so I went to Grand Rounds because that was the right thing to do. And he said, if you have a patient with erectile dysfunction, they have diabetes until proven otherwise. And I nearly fell out of my chair. Now, 2001, no one was talking about this.
You're so right.
Heyday of my Viagra, you know, you just kept giving your patients Viagra like it was. Like it was candy. And you couldn't even keep samples in the office because the male physicians took them home. And I just remember Art Serpic was this incredible surgeon, and I remember him saying that. And I. I was like, looking around, like, we didn't learn this. Oh, my gosh. And so from then on, it's like, I. I think if you grow, if you have a. A natural curiosity to understand things at a level like, I constantly want to improve upon what I know. Even now, I. I mean, I. I actually just signed up for another course. My husband's like, why are you taking another course? Because I always want to know more.
It's true. And. And our learning is lifelong. It's lifelong. And every single day we are discovering more and more ways to get and keep people healthy. But if you're. If you don't have that, that curiosity turned on, if you're not seeking, it's not going to come to you.
No.
Right. We have to be constant information seekers, constant truth seekers in order for this to happen. But the amazing thing is that it can if you let it.
Yes, yes. The ability to critically think is sometimes, I believe, a lost art form. I think this is something I was trying to give an example in context to my children who've never worked in health care. They have zero desire to be a doctor, any type of healthcare provider. But I will sometimes give them examples. And I was saying, you know, I was rounding on a complicated patient, and I got a call from a nurse who will remain nameless. And the question the nurse asked, I was like, do I need to hold this drug for this patient. And clearly he didn't understand the mechanism of action because if he did, he wouldn't have asked me that question about this drug. And so the first thing I said was, I'll call him William. William. What would be, what class of drugs is this drug in? And so he mentioned it and I said, and how does this drug work? Long pause. And I said, william, I want you to go look it up and then I want you to call me back. But I looked at my colleague and I said, as an ER nurse, we were expected. We didn't give a drug until we understood the mechanism of action backwards and forwards. Because someone would have bitten my head off if I had called a specialist from the ER with that question. I was shocked. But I think there's sometimes individuals and it's not unique to medicine, but sometimes people just don't think. They just don't even think critically. And so that in and of itself is. It's a major problem, not unique medicine. I think it happens in any field. But I think that that natural innate curiosity and the desire to be a lifelong learner is something all of us should embody.
Yeah, for sure, for sure. Everyone. Everyone. Not just health care providers. Right? Everyone. So let's get back to insulin resistance, because that term is thrown around a lot and most people don't know what it means. So what does it mean to be insulin resistant? And then I want to make sure that people have something that is actionable to take home today so that they can start to own and improve and optimize their metabolic health.
Yeah, I'm so glad you asked this question. So insulin resistance is really speaking at a cellular level, so we'll get a little scooch sciency. So we have insulin receptors on our, on the side of each cell. And over time, if we have very high glucose. Glucose, and it's, it's making these, these receptors less sensitive to the hormone of insulin. That helps like a lock and key, move the blood glucose into the cell. Insulin does that. That's the mechanism of action, one of many actions over time. It's almost like someone's knocking on your front door, but you can't hear them. It's just, it's like over time, with this prevalence of high blood glucose, it will weaken this receptor activity. And so this is reversible. I want to be very clear. This is something that's completely reversible, but it's also very important because insulin resistance is at the basis for every single chronic health problem that we see in the United States from polycystic ovarian syndrome, which is an infertility problem, to cognitive disorders, Alzheimer's, Parkinson's, heart disease, obviously diabetes, metabolic syndrome, breast cancer. I mean, there are colorectal cancer. There are so many issues, all these chronic diseases, high blood pressure. What people don't realize, they'll say, oh, I eat too much salt. No, it is because you are becoming insulin resistant. Remember, those cells are not able to utilize.
Yep.
Moving blood glucose into the cells. So when we talk about things that can help metabolic health, I like to keep things really, really simple. Number one, walk after meals. If you do nothing else, take a 10 to 15 minute walk after meals. Because you actually have transporters in your muscles that kind of are utilizing glucose. So if you have a continuous glucose monitor or a glucometer, you can look at your blood sugar before you walk in after. And we know that a 10 or 15 minute walk has a really positive net impact. So physical activity is number one, because we actually start with insulin resistance in our muscles. So as we are losing muscle as we get older. I know we didn't talk about that. That can also influence why we become less insulin sensitive. Also changes with sex because your muscles.
Are using that glucose. Right. And as we get older, most people start to lose their muscle mass.
Sarcopenia.
Yeah. So if you lose your muscle mass, there won't be muscle there to uptake that glucose. And so that's when. That's part of why people get into trouble with blood sugar management.
Right, Absolutely. So I always say this is where, you know, north of 40, our body starts replacing muscle with adipose tissue. And adipose tissue is not just fat, it is a metabolically active tissue. Inflammatory cytokines, other types of substances that. It is not a benign entity. So think about young. Young muscle looks like fillet and older muscle looks like a ribeye. Still delicious, right? But that's, that's if you want to just think about that visually. So number one, walk after meals. Number two, everyone listening should be able to eat in a 12 hour window of time. Now, I'm not saying everyone, intermittent fasting is right for everyone at the very beginning, but understanding that we should not be eating for 14, 16, 18 hours out of the day when we get up in the morning and maybe we have breakfast at 7am and then closing your feeding when maybe you have breakfast at seven, you have lunch at one and then you have dinner at six, knowing that after dinner you don't continue eating. And really the whole concept of meals should be really just a meal Two to three meals a day. It is not. I graze all day. I have five snacks in between each meal. That gets people into trouble. And they don't understand that if you don't put your macros together properly, your protein, fat and carbs, that can be problematic. So understanding. Like my teenagers eat in a 12 hour feeding window. I'm sure they're just like your boys. They eat from the moment they wake up until they go to bed. But they really do have large boluses of food. They don't get hungry in between because they put their meals together properly. That's number two. I think about the concept of rest. I know for a lot of women in particular north of late 30s, early 40s, when they really start struggling with some of the sex hormone changes, you know, the loss of ovarian function, less circulating progesterone, they can start having trouble sleeping. Sleep is foundational to our health. It is underappreciated, undervalued. I encourage everyone to aim for no less than seven to eight hours a night of sleep. It is so important, so restorative. You need a good amount of deep and REM sleep for different reasons, but most people say, you know, what's the minimum? I usually say at least 90 minutes of both. If you have an OURA ring like I wear, I can kind of track my metrics. Not to be obsessive, but just for validation, like, okay, I had a good night of sleep. Sleep quality is very important if you're not sleeping well. The question is, why is it alcohol use that's disrupting REM and deep sleep? Is it where you are in your menstrual cycle? We know as women get closer to their luteal phase and they have fluctuating amounts of progesterone, usually lower amounts of progesterone heading into menstruation, that can impact things. Chronic stress, again, we've all had a lot of stress over the last several years. All of which can impact that.
Screens are a big part of that though.
Yes. How many people?
Blue light at night.
Yeah. And so blue light will actually suppress a hormone called melatonin. And if melatonin suppressed, guess what hormone is not suppressed? That's cortisol. And cortisol is a not a bad hormone. But cortisol is the get up and go hormone. You know, people say they get that second wind at 10 or 11 o' clock at night and they start binging Netflix. I get it. But we want to be conscientious about screen exposure. That includes your Your, your iPhone or your, your tablet or your computer or just being under bright lights in the evening, especially now we're heading into fall. So certainly, you know, as we're heading into cooler weather months, you know, just being conscientious. I wear blue blockers in the evening. If I have to be on my computer, it does it for me personally. Makes a big difference. But melatonin also, we start making less of it production wise after the age of 40. It's not just sleep hor also a master antioxidant. So I'm glad that you brought that up. But I would say, you know, the big things that are, that are low lying fruit, number one, walk after your meals, 10 to 15 minutes. It's also good just to be physically active. That also helps asleep. Number two, really aiming for meals, not snacks. You know, I always say we're grown ass adults, we should not be snacking.
That's exactly, exactly. People ask me all the time, what do you do for snacks? And I'm like, I don't, I'm not two, I don't need a snack.
I know my kids know, they're like, they're like, oh, there goes mom again. And I'm like, yes. You know when you're, when you're a little person and you can't pro, you're just growing so fast. Very different. None of us need snacks. And I always say if you, if you're hungry in between meals, it means you needed to have eaten more food, more protein, more healthy fats. I mean that for a lot of people. And the other thing that I would say that I think is important to kind of tie into this is that as we start losing muscle mass, it becomes even increasingly more important to strength train. So for all these women that are still like cardio bunnies, they want to run 10 miles a day, seven days a week. And they wonder why they're haggard and tired and they can't lose the weight. You'd be better off, you know, doing some zone two training, doing some strength training, walking in nature in the morning. I mean there's so many things that you can do. But we want to maintain muscle mass and number one, we need to lift. And number two, we need to eat enough protein. And what I find is most if not all women eat half of the amount of protein they should be consuming. So at least 30 grams in each meal because that will trigger something called muscle protein synthesis when a certain threshold of leucine is, is met. And that is what will help build muscle. And so to help people understand. And the easiest way to do that is track your macros, like Chronometer, no affiliation with them, but I always say free app. It does a nice job tracking. Just even if you build awareness around the fact that you're under eating protein, that in and of itself can be really, really helpful.
So I wanted to ask you, while we're on this topic, the order in which you eat your food matter?
I think so. I always say when. So obviously I intermittent fast. But I always say protein is always consistent. Protein, protein, protein, protein and healthy fats. Like if you sit down and have a salad with chicken and avocado and greens, or protein and carbohydrates. Like you sit down and have a piece of steak with broccoli, Never having carbohydrates by themselves, always having protein. That is what is going to help stabilize blood sugar. It's going to help with satiety, it's going to help with those stretch receptors in your gut. And so carbs are never, unfortunately that. It's like a new term. Carbs are not consumed naked. But that's where people get into this issue related to blood sugar dysregulation. And we know the very first meal of the day is actually the most important for blood sugar regulation for the entire day.
Yeah.
Look at the research. If you sit down and have, you know, four eggs and avocado and maybe you have some, you know, low glycemic berries, that's going to set your day up better than if you sit down and have a bowl of oatmeal.
And I hear this all the time, that I have people with fasting insulins in the teens and twenties and thirties, and they're like, but I mean, I have a bowl of oatmeal every day with berries. And I'm like, yeah, that's not good. You're starting off your day craving carbohydrates. And it just continues throughout the day.
Right.
It really does set the tone.
It does. And so they talk about this concept of hyperphasia or this desire to continue eating. And you really do need that first meal to hit that protein threshold because that will keep you satiated, keep your blood sugar stable. And that's important. The reason why you continue craving more food is because your blood sugar spikes up and comes back down. And so that's always a tell. I remind people, the tell is, do I feel satiated? If you're not satiated, the question is, why? And so very, very important, you know, the, the whole. I find chronobiology Fascinating. You know, the whole kind of looking at the distribution of cortisol throughout the day and how that's impacted by meals and, you know, exposure to sunlight and exposure to darkness. And again, we're more insulin sensitive earlier in the day. So it makes sense to eat when it's light outside and not when it's dark outside. That may not be able to be the case 100% of the time, but it's kind of a good adage to kind of live by, to understand that intrinsically our bodies really are connected to the earth and connected to, you know, wake cycles, sun exposure, etc. I know, you know, years ago, probably much like I did, you know, call schedules up in the middle of the night, you know, working crazy hours, I don't miss that at all. But if you look at the research on ship workers and what happens to, what can potentially happen to their health.
Yeah, they are, they're susceptible to chronic, more chronic disease. Like 30% increase in risk for chronic disease all across the board. So it's, it's heart disease and it's cancer and it kind of everything because they are so shifted. So with that in mind, do you change your, your fasting routine according to the time of the year? Because in the summer our sunlight hours are much longer. So do you have shorter fasts during that time and longer fasts in the winter?
You know, I've been, it's a great question. I've been experimenting with different fasting windows over the past probably six months to kind of see how I do with adjusting protein macros. Like do I need two meals to hit my protein macros? Do I need three? I personally do best if I shut everything down by six o', clock, like, that may mean that I'm sitting with my family watching them eat dinner and they're eating dinner at 7:30 or 8:00 clock at night. I think for me personally it was the pandemic that allowed me to realize like I actually, if I look at all of my metrics, I look at everything that, you know, all my sleep metrics and how I, my perceived sleep improvement. I do much, much better eating or like finishing eating earlier in the afternoon or, or cutting things down by six o', clock. Can I get by? I was just in Europe. Can I get by with eating in the evening? Sure. But as a rule I just sleep a whole lot better. And sleep has become so important. Like my whole family makes fun of me. They're like, sleep is so important to me that I adjust things just based on how I'm feeling, but I'm pretty consistent. I find that I don't do really well with a very tight window. I just can't get my protein needs met. But obviously there's always exceptions. But I find for me personally, I just do. Irrespective of time of year, I do best kind of shutting everything down by 6.
I personally think that everyone benefits from a CGM, a continuous glucose monitor. I think that this is really valuable information. Can you go ahead and talk about that a little bit and give people the information of what they are looking for in terms of metrics, because they're not going to be able to measure. They're fasting insulin by that, obviously, and they're not going to be able to measure insulin response. But you can get a lot of information from knowing what your glucose response is.
Absolutely. So a continuous glucose monitor is a device that you wear. It's actually a little microfilament that sits in the interstitial space. So it's not inside your vasculature, it's sitting in the interstitial space. But we can get actually very good information from this. So when you wear a CGM, you're wearing it usually for 14 days, and you usually will get an app that will allow you to trend data. So, ideally, in a fasted state, I like to see blood glucoses in the 70 to 85 range. So I'm saying if you wake up in the morning and that's where your blood sugar is, that's great. Now, obviously, things impact blood sugar like stress, like exercise, the foods we eat, you know, being happy, being excited. In fact, I took my CGM off last year during the book launch because every time I got excited to get on a podcast interview, my, my, my cortisol would go up because I was excited, and then my blood sugar would go up. And so I just watch all these crazy variations. What we're really looking for is consistency. I always think it's helpful to know what is your fasting blood sugar, what is your blood sugar when you get hungry? Because that can be very valuable information. Like, let's say I wake up, my blood sugar's 82. And then, you know, throughout the course of the day, I'm hungry and my blood Sugar is like 76. So for me, what's interesting is because I fast, I'm kind of attuned to how I feel when I start getting hungry. And my big tell is the weather starts getting colder as I get cold. That's how I can typically tell. Like, I'LL get hungry, I'll feel a little bit cold. I'm like, okay, I need to get up and move and go get some food. So knowing what your numbers are when you are hungry is important. Sometimes people run in the 90s, sometimes they're 87. I mean, there's a wide variation. What's interesting is what is your blood sugar before you eat and after. This is very important. So let's say you get hungry and your blood sugar is 90. You eat a meal, you look at your blood sugar 30 minutes later, 60 minutes later, it's gone to 150. Now, this is valuable information. Number one, you got too high of an excursion. We don't ever want to see more than 25 ish points increase in your blood glucose. Now, does that occasionally happen? Yes. You had a birthday party at a piece of cake. Maybe you went out to an Italian restaurant, you had some pasta or some bread, or maybe you had wine or dessert. But 25 is about my threshold of where how much I want to see that blood glucose go up. I want you to think about the fact that when your blood Sugar goes above 140, we're really starting to see and witness, you will get changes within the vasculature. You can actually start having some damage to that intimal lining, which the lining to the inside of that blood vessel. And if it happens a few times, that's different. But if it's persistently elevated, every time you eat, you have this exaggerated blood sugar response. You need to think about what did you eat? So number one, did you sit down and eat a bowl of pasta with no protein? That can sometimes do it. If you sit down and have bruschetta and then you have a big bowl of pasta and then you have a couple glasses of wine and then you have a big dessert. Like very little protein, probably not the right types of fats and a lot of carbohydrate versus you start with some fiber. So maybe you have a salad, you drink some water, then you have a main course with protein. Maybe it's chicken, maybe it's fish, maybe it's a piece of steak, bison, et cetera. You have some non starchy vegetables. I bet your blood sugar response is going to be minimal because you've had some fiber, you've had some protein. This will help mitigate that blood sugar response. And then if you choose to then have a dessert or maybe you have a piece of fruit or something else, you have a much more, you know, kind of stable blood sugar. So it's Always in the context of where were you when you started and where was your blood sugar when you, when you finished your meal 30 minutes later, 60 minutes later, two hours later? Very, very valuable. And I find many people don't realize, like, as an example, you know, they go, they go exercise and they'll say, oh my gosh, I got this huge blood sugar spike. Well, that's, that's different. In the context of intense physical activity, you can get some release of stored glycogen, which is stored sugar. And that can happen because your body is trying to effectively free up a fuel source to be able to fuel your body. But in the context of food, where were you when you started eating? And where were you 30, 62, 60 minutes, two hours afterwards? Now we want to see your blood sugar come back as close to baseline as possible within that two hours, ideally. Does that always happen? No. There's probably people listening that'll say, my, my blood sugar when I get up in the morning is 110. It's 100. When I eat, it goes to 150, 160. Remember what I said earlier that insulin resistance is a, is a problem we can fix. It takes time. It takes time for those insulin cells to become, or those, those cells, those cell receptors to become desensitized to the effects of insulin. It will not get fixed overnight. And usually where it shows up for my patients and clients is in the morning. Fasted sugars, like, they'll, they'll, they'll be very fixated. I don't know why. My blood sugars are always bad, bad in the morning. And I remind them that sometimes that is the last thing that I'll see improvement with is that morning blood sugar in that fast state. But really trending. Like, write down what you're eating, monitor what you're eating. For some people, it's like very benign, sneaky things. They go out to a restaurant, I had sashimi without the rice, and I said to my husband, because I had such an exaggerated blood sugar response, I kept saying, oh, there must have been something probably in the salad dressing. I mean, sometimes when you're eating out, you can't control all the variables. You can't control all the ingredients. And sometimes it can be sneaky ingredients, like there's sugar in a dressing or there's sugar in a condiment. Just crazy things that can have a large net impact on blood glucose response. So that's usually how I kind of look at it in the context. Like, don't stress about every single increase in your blood sugar. But like, look at trends and most of the apps, whether it's, you know, the, the one that I like is the Freestyle Libre, it's pretty easy to use, they have their own app, there's other companies, levels, nutrients, etc, they can give you more advanced things to look at, like averages and you know, what's your overnight excursion, you know, what's your blood sugar after a meal. I mean there's a lot of different fancy metrics and the apps are getting.
More and more sophisticated in that like some of them are actually offering up advice to you.
Yep. Yeah, their Nutrisense is an example. They typically will give you a registered dietitian and that can be very helpful. But it's like making where are you in your menstrual cycle? So if you're still getting a cycle, we know you lose insulin sensitivity in the luteal phase, so that changes in estrogen and progesterone can impact insulin sensitivity. We know women in perimenopause and menopause start losing insulin sensitivity and so a lot of it can be where are you in your cycle? What stage of life are you in? Are you on hrt? I mean, there's all sorts of like different avenues we can go down. But I do find that for most women in the latter stages of perimenopause and menopause that have the best insulin response, are physically active, they monitor their stress, they, they sleep well, they're probably on some HRT because that does make a big, big difference. And then, you know, they're conscientious about their nutrition. It goes without saying you cannot, as a 50 year old woman, eat like you did at 18 and think that you're going to have the same results. It is physiologically impossible.
Yeah, absolutely. So you did say that it takes a while for that insulin resistance to change, but it does, it does take as long as people think. Don't people start seeing results in a.
Few weeks more often than not. So if someone's on diabetes medication, lipid lowering agents, blood pressure meds, the first thing I tell them is talk to your internist because I want you to go see them. Because yes, you can start seeing alterations in blood pressure and blood sugar, sometimes they need less diabetes medications. And so yes, but it's interesting how that dawn phenomenon like that, that cortisol and blood glucose response in the morning, that is sometimes the last thing that I'll see actually improve. And I don't fully think I've ever gotten a great explanation for why that is. But I do agree that in many instances, people, like, will start seeing shifts in the scale. They'll see changes in composition, they'll, you know, be on less medication. And I'm like, there is no greater joy than when a patient says to me, I just saw my primary care provider and I'm on one less medicine. Because to me, it is. We are going against the grain. We are going against the traditional kind of allopathic model, which is, you know, just prescribe more meds. Like, don't talk to the patient about lifestyle, just prescribe more meds. That's how we're going to deal with it.
Yeah.
And then the patient becomes beholden to the pharmaceutical industry and that, you know, I don't think that our bodies aren't designed to take 15 or 20 different medications. I'm sure.
And beyond that, people generally don't feel better. No. Right. Like, they, their. Their numbers may be managed to some extent, not. Not to a great extent, but they don't feel better. And that's a problem. And the very same things that brought them to the doctor in the first place, because they weren't feeling well, they don't feel any better on these pharmaceuticals. And I do want to mention, because I know we talked about a lot of the things that elevated blood sugar does. I mean, I know that we talked about, certainly it can be associated with breast cancer, diabetes, kidney disease, eye problems like glaucoma, heart disease, infertility, Alzheimer's, high blood pressure, kidney failure. But every time you eat sugar and your blood sugar spikes, and that can be sugar. It can be a bowl of oatmeal. It can be whatever is spiking your blood sugar. You are immunosuppressed for five hours afterwards. And breast cancer is, like, at the end of a long road of immunosuppression over time that has resulted in the expansion of a cancer cell population. This is so intimately tied to our immune system. The more imbalance we have in our metabolic health, the more likely we are to develop cancer because it's having direct, profound negative effects on our immune system.
I think that's probably not an angle a lot of clinicians talk about. It's like if you need further validation to course correct, it's understanding that it's not just. It's not just impacting you on a metabolic health perspective. It's impacting your immunity. I mean, look at what happened over the past three years. I mean, I was just listening to a podcast this morning, and they were talking about, you know, long haul Covid and talking about, you know, the mitochondrial dysfunction and how, you know, they're now able to kind of look at, you know, the individuals that have fared the worst, and I'm like, it's incredibly sad. It's incredibly sad.
Yeah, but those are also the people that started off with metabolic disease. And so dysfunction begets dysfunction. Right. And. And those are the people that handled that viral attack the worst. And it's because they went into it immunocompromised and their immune system couldn't appropriately respond. I know that we need to wrap up, but I do want to ask you, is there anyone who you don't recommend fasting for?
Yes. I'm not a fan of fasting for pregnant or breastfeeding women. I feel like, you know, while you are growing a human or feeding a human, it is not the time to restrict your macro intake. I think for anyone that has, you know, brittle diabetes, if they're not aware of how they feel with a low blood sugar, that's obviously a concern. Learn. It's not a strategy for children. And if you're not done growing, like, I, I sometimes will get questions across social media like, oh, my teenager's obese. I think they would really benefit from intermittent fasting. And I'm like, first of all, you know, you need to talk to your pediatrician. But if they're still growing, that's not a strategy you want to use. There's other things. Like you could do a low carb, you know, you could use a low carb approach, and there's certainly good research on that. The other thing that I think about is people that have significant chronic health problems. This doesn't mean that intermittent fasting might not be appropriate for them. But this is why I always loop in the internist, the primary care provider, so that someone is monitoring those metrics. Because, you know, for every patient that will monitor their blood sugar and monitor their blood pressure, etcetera, I had five times as many that were not willing to do any of that. And so I think someone needs to be the quarterback, someone needs to be overseeing to see if you need an adjustment in medication. Those are typically the, the ones that I get concerned about. I would, I would add also people with a disordered relationship with food, whether that be binge eating, anorexia, bulimia. Are there exceptions? Yes. Occasionally they'll reach out to me on social media and say, hey, this has been a great strategy for me. I'm working in conjunction with my eating disorder specialist and they gave me the go ahead and they're monitoring me really closely. But I do think that in particular, anorexics sometimes will use intermittent fasting as a means of kind of hiding their eating disordered behavior. So again, there's always exceptions, but those are individuals that. I kind of have a pause. I'm like, yeah, unless your primary specialist therapist feels like you're ready for that stressor, I would probably say I would pass on it. Yeah.
Yeah. And I agree with you there. But I do think for most people, and I actually think that anyone can go overnight without eating. I don't think anyone should be getting up in the middle of the night and eating. And if you are doing that, you really ought to be asking yourself why.
Exactly. That's why I say the 12 hours. Like, even the teenagers who seemingly could eat me out of house and home any day of the week, they. They actually will talk about it. They're like, I probably go 12 hours of that eating because by the time they get home and they've had their second dinner and then, you know, before they eat again, and they're, you know, very athletic and very muscular and very conscientious about working out. And they're like, yeah, probably the time I'm sleeping, and then until I decide I'm hungry in the morning, and I'm like, yeah, perfect.
Yeah.
But that's how we're sleeping.
Exactly. Exactly. Because if you were eating after dark, from an evolutionary standpoint, you were.
Yeah.
It was most likely that you were the food. Yes. You were getting eaten.
Exactly. Exactly. And that's why I always say, like, eating when it's light outside, not when it's dark outside. No. My teenagers would laugh at me if they heard me say that. But my husband and I really have started kind of embracing that. And, you know, we sleep so much better. I'm like, gosh, I used to make.
Fun of the early bird special, and now I'm. Now I am the early bird special.
But you know what's funny? I always say the laugh is on them because I go to bed not having a full stomach.
Yeah.
I'm not drinking alcohol, so my sleep is pristine.
Yeah.
To me right now, like, right, Exactly. Sleep is king. But, yeah, I do have family members that. That make fun of me, and I'm like, I just accept that. I'm like, that's fine. This is my not be yours. But I feel good about where I am, so.
Excellent. Well, I think this is a great time to conclude. I thank you so much for being here today and for sharing all your brilliance. And all your wisdom. I thank you so much for doing what you do for the people that you help, for being eternally curious and really making this world a better place. You left clinical medicine and. And conventional medicine to help a lot of people, and I know you have.
Oh, well, thank you. Thank you. Likewise.
It's Dr. Jen. Until next time. Bye for now.
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