In this episode, I am speaking with Dr. Stephanie Estima – who is an expert in female metabolism and body composition. We will talk about the application of the ketogenic diet, fasting, and exercise for female physiology.
Table of Contents
In this podcast, Dr. Estima and I will discuss:
- The fundamental unique aspect of female physiology that differs from men (and why it matters)
- Why studies tend to favor men (and how it can influence work tailored to women)
- The different types of fasting (And the best way to fast for women)
- The best protein levels for women
- Why you shouldn’t fear heavy weights
- The danger of sarcopenic obesity
- The consequences of long-term restrictive eating
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Listen outside iTunes
Ari: Hey there, welcome back to the Energy Blueprint Podcast, I’m your host, Ari Whitten. Now with me is my friend Dr. Stephanie Estima, who is an expert in female metabolism and body composition. She specializes in the application of the ketogenic diet, fasting, and exercise for female physiology, and that’s what we’re going to be talking about today. Using her framework, the Estima method, she is focused on distilling strategies and nutritional proxies movement, posture, and mindset to actualize female potential.
Dr. Stephanie has lectured at conferences and corporations over the past 17 years, is one of the top writers on Medium, and has been a featured expert in Thrive Global and on various morning TV shows. She hosts the podcast Better with Dr. Stephanie and lives in Toronto with her three children that she is currently homeschooling due to COVID-19, as we were just talking about before we started recording.
Welcome, my friend, such a pleasure to connect with you again after talking to you just a couple of weeks ago recording an interview for the upcoming Superhuman Energy Summit.
Dr. Estima: I’m excited to do this again. It was such a wonderful chat. I told my partner after our conversation, I was buzzing. I just love geeking out with you. I think I said this on the what, last time we spoke that I felt like I could geek out with you for forever.
Ari: For sure.
Dr. Estima: Round two today.
The difference between men and women when it comes to weight loss and exercise
Ari: Yes, the feeling is very mutual, hence why you have returned for round two. Let’s talk about overview of why there’s even a need to specialize in this area of tweaking things to optimize female physiology. What is unique about female physiology that differs from men? Obviously, there’s different sex organs, there’s a menstrual cycle, but fundamentally, what is different that makes them respond differently to different things?
Dr. Estima: What I wanted to talk about in terms of how women are unique are both– Obviously, the menstrual cycle is something that makes us distinct and unique and gives us our unique hormonal landscape and environment. The other things that make us unique are even hormones that we share. We have metabolic hormones that both men and women have, leptin and cortisol, which are two that I want to highlight that behave differently in women. Then, we even have organs that are– We have livers, men and women have livers, but the way that they express certain hormones like growth hormone, which we’ll talk about, is also unique and different. For the longest time, women have just been viewed as little men or these smaller versions of men that have a menstrual cycle. I think it’s important for us, when we’re thinking about devising protocols, we have to take into account a woman’s unique physiology, like her menstrual status, whether she’s fertile and having a period every month, or if she should be and she’s not, whether she’s peri- or postmenopausal. All the way through our lives, we have this unique landscape. There’s also, of course, the opportunity for derangement in those hormones. I think it’s important for us to consider females being different and unique, and we’re not just small men.
Ari: I’m debating in my mind whether to even broach this topic because it’s a charged topic, but I’m just curious to get your thoughts given your area of specialty. There is a growing concern or it’s been a concern for a while now around the discrepancy between the amount of research that’s been conducted in men versus women over the last century. I have no idea what your actual views on this are, but there’s everything from like, “There’s zero research on women. There’s this massive oppression of women, and science doesn’t feel women are worth studying.” That viewpoint, which is very much connected to the feminism movement. Then there’s more of a viewpoint that’s like, well, the menstrual cycle inherently adds more confounding variables to research. That’s why, in general, even in animals, there’s a discrepancy in animal models, in rats, there’s a discrepancy of more research on male rats than female rats. It has nothing to do with a systematic oppression of women. It’s more about just trying to get more clarity in the research, and less confounding variables means clearer, cleaner research results. I’m just curious about your thoughts on the landscape. Then maybe more than your just political views on the situation, but your thoughts on how this manifests in terms of to what degree we have a paucity of data on knowing the details and intricacies of female physiology.
Dr. Estima: I think I tend to be less of the “we’ve been excluded on purpose” to more of the “it does create confounding variables”. I guess the issue with that, so females have been excluded from like everything down the line because of these confounding variables, but the thing that I think is missing is life is not a lab, life is not this really clean controlled random double-blinded, you can’t have that in real life. I think there is a difference. This is where I think the clinician is so important because then we can go from taking information, so the literature that you publish in a double-blinded RCT, where it’s very clean, very controlled conditions, and you apply that information in real life. This is really– We can get into a larger discussion around evidence-based medicine and evidence-based practices. That’s actually what evidence-based practice is, is looking at the information, looking at what the goals and dreams are of the patient, and then relying on the clinical experience of the clinician to be able to apply that, in the case of women, it’ll be his or her understanding of female physiology and how that literature, how that information parses with that in order to apply it. When you see– This is totally a different topic, but there’s so many online, I would call them online bullies that are just like if there’s no RCT, there’s no evidence for it. For me, I like to abide by that lack of evidence is not evidence of lack. You have to be able to take the information and use your clinical expertise in order to create something in line with a patient’s goals. This is–
Ari: By the way, the proper term for them is evidence-based internet trolls.
Dr. Estima: EBITs yes, I have seen that. They’re really cruel. There’s so many times when I have created programs for women and– I also say this, the literature is actually relatively clear for obese women. For obesity, the literature is relatively clear. It gets muddled when there’s literature looking at a woman like myself with a healthy BMI, not many hormonal issues, but I want to play around with fasting, for example, and we can talk about some of the different– I like to call them different leavers of fasting, like how we can manipulate fasting, but there’s actually not a lot of information for a healthy woman like myself who wants to get a piece of that longevity pie. We hear about the longevity and the FOXO3 and all these fun things and I’m like, “Okay, I want some of that. I’m healthy. I want to fast,” but there’s not a lot of information for a woman who is within, let’s call it 5 to 10 pounds of her ideal body weight and to fast for long periods of time or to engage in different types of fasting or noncaloric liquid fast for her to do just like a pure water fast for five to seven days. There’s not a lot of evidence there. What you have to do is become your own guinea pig as a female. That’s in my modus operandi where I have said, “Okay, I’m going to fast and I’m going to watch my markers. I’m going to see what happens. Then I’m going to do that with my clients and see what happens.” Then over time, you develop this clinical picture of what happens for females when they engage in longterm fasting, for example, for using that as an example.
Ari: Just to loop that back into the EBITs, the evidence-based internet trolls, what you end up is a– I’m saying this to the listener. I want them to understand this landscape because you have experienced clinicians who are extremely well read on literature, have a deep understanding of physiology and biochemistry, and are using that knowledge to go beyond the current state of the literature to explore the frontiers, to test things, to try new things with themselves, with their clientele, their patients and they’ve developed this large body of clinical experience over many decades that’s a direct result of lots and lots and lots of expertise and experience. Then you can have some 21-year-old PubMed warrior who knows a tiny fraction of what someone like who knows who goes on PubMed for five minutes and says, “Hey, your claim around fasting and women, I couldn’t find any studies to support it, therefore, you’re a quack and you’re saying nonsense.” I just want listeners to understand how ridiculous this can be at times when you have somebody who has no real knowledge and no experience criticizing someone like yourself, or like myself, who’s been doing this for a very, very long time and is trying to say, “Hey, we’ve studied the literature and let’s connect the dots and try this, this and this, logically speculating, based on physiology and biochemistry. This probably would have benefits. This probably would have benefits. Let’s try this good safety to benefit profile, worth a shot and may have real benefits.” Then you get the EBITs trying to criticize based on lack of evidence.
Dr. Estima: This is where like information and application are, in my world, in my opinion, two distinct things. The information is available to everybody. Of course, not all information is equal. The quality of the study and all of that, but the application of the information is really where the magic happens. That happens after many failures. That happens after you falling flat on your face and trying a theory that should work in theory but doesn’t actually work in real life because it’s not a lab.
The best fasting guidelines for women
Ari: Let’s talk about fasting. This is a controversial topic among different experts when it comes to women, especially. Some people are saying, “Hey, fasting is okay for men, but it’s fundamentally bad for women. It doesn’t mesh with our unique physiology and biochemistry and hormonal nuances.’ What’s your take on fasting and women more broadly? Then since I know that you use it, what’s the appropriate context and methodology for experimenting with it?
Dr. Estima: I would say that any large sweeping statement like ” fasting is not good for women” is always just going to give me a little bit of a tick. The devil’s always in the details. When we break down fasting, I think fasting can be very appropriate for females, but we want to think about fasting in a couple of different ways. The ways that I like to talk about fasting is we like to almost pull like three different leavers; there’s the type of fast that you can engage in, there is the length of fast – that would be another lever, and then there would be the frequency of the fasting. When we think about types of fasts, I talked about one just before, like a noncaloric liquid fast. That would be water only. It could be herbal tea, I’d include black coffee in that. That could be done daily. It can be done on what many people call it intermittent fasting. I don’t like that term. I think it’s a little too broad. I would tighten that nomenclature up and say that more of a time restricted feeding window. You’re still eating every day, but you’re just restricting the time in which you eat food. You can have changes in the length of your fast. Like I said, it can be a daily time restricted feeding window. You could have a 24 hour fast or 48 hour, 72, 96, et cetera. Then the frequency of your fasting. Are you doing this daily? Are you doing a different type of fast, weekly, monthly, quarterly? When you think about those three different leavers and all the different possible outcomes, there’s a lot of different ways to fast. You can apply this to women who need to lose weight. If you have someone who has excess adipose tissue, has been told by his or her primary that their cholesterol is out of whack or their lipids are out of whack, you can play with more aggressive type of fasting or even some of the gentler fasts are very, very applicable for that. You can have a different lens of fasting for women with hormonal derangements. A woman with PCOS where she’s not switching or remotizing her testosterones to her estrogens appropriately. I have had massive success with noncaloric liquid fast, what we call OMADs, or like one meal a day. She’s still eating every single day, but she’s doing essentially a 24 hour fast multiple times a week. I’ve had incredible success with that. Women who are estrogen dominant, whether you’re in the early phases of perimenopause or you just generally have a lot of PMS around your cycle, playing around with caloric liquid fast. A caloric liquid fast might be a bone broth. Fast, it might be abstaining from food but you’re having soups or you’re having like a fatty coffee or a fatty tea in the morning. You’re still getting some calories from the fat, but you’re not spiking up your insulin. That also helps with gut repair, which is often an issue when we see women who have excess estrogen in the luteal phase of their cycles, so helping with liver detoxification, but in particular like gut reparation.
Then there’s also fasting mimetics. You can do that in terms of like– Technically, a ketogenic diet is a type of fasting mimetic because you’re restricting a one macronutrient carbohydrate. Then there’s also– I know Dr. Valter Longo has ProLon. I’ve done it. He gives you little packets to eat every day. It’s like you get like five olives, then you get some squares and stuff. You can honestly reproduce that on your own by having like some broccoli in avocado. It’s a mode of caloric restriction. One day you have let’s say 800 calories and then there’s like a stepwise attenuation from there. That’s a longer answer, but what I’m trying to get across is fasting is nuanced. There’s a lot of different ways that you can pull those levers and apply them to a wide variety conditions In order to help improve them.
Ari: Is there a map of the territory when it comes to fasting? If someone is, let’s say a very fit, lean already, very healthy and energized energetic person, such as yourself versus if someone’s very overweight they’re sedentary, they’re on the standard American diet. They can’t go more than two or three hours without eating something because their blood sugars levels crash due to metabolic inflexibility, insulin resistance, et cetera, is there any general map or blueprint of maybe what those people should start with when it comes to fasting versus maybe someone who’s already very fit and healthy and energetic, where they could play around and experiment with.
Dr. Estima: Women or someone who is following a standard American diet, the first thing that we want to do is they’re probably eating a lot of processed foods, they’re probably eating what I’ve– I have typically found and I’ve read this as well. This is both my own clinical experience, but I’ve also read this with other clinicians and in the literature, is that typically, and this is more true for North Americans. North Americans who are following that standard American diet we typically are eating at all hours of the day. All of our waking hours from the moment that we wake up to the moment that we go to sleep, is when we are snacking on things, we’re eating meals, we’re eating foods in between meals, having bars and smoothies and all this kind of stuff. What I like to start off with for women who have excess weight to lose, is to just start to tighten up. We want to just start general and then get more specific as we go along. I like to really work on improving their circadian biology or factors around their circadian biology first. That’s going to start with meal timing. As it relates to fasting specifically, the first thing I’m going to do is ask them to do a 12:12, which Is 12 hours of fasting, and of those 12 hours, hopefully, eight of that is sleep. You’re sleeping for, let’s call it seven or eight hours. You have four hours left where you are going to be restricting. You either add that on to the four hours in your morning, four hours in your evening, which is actually what I really prefer, or you can split the difference. You can have two hours in the morning or you abstain from eating and then two hours in the evening. I really, really love to, once I have someone on that 12:12, however they choose to apply it, to really do that night limiter because that is really how we are– It has a knock-on effect with sleep. As you allow the stomach to empty, you give your stomach two to three hours to empty, then when you’re lying parallel, when you’re in bed, the reflux and the acidity in the stomach that is required to break down the bolus of food that you’ve eaten, is now not going to eat away at the sphincters and the esophagus. There’s not going to be any reflex there. I really, really love for people to start off with the 12:12 and then I will move the 12:12 earlier so that they will start eating earlier in the day so that the eating stops earlier in the evening. From there, once they habituate to that, it’s about tightening the eating window. If they’ve been doing it 12:12 for a couple of weeks, then I’m going to say, “Okay, so let’s do a 10:14 now.” Now you’re going to eat for 10 hours, fast for 14, so it’s just a little bit longer than the 12. I will continue to tighten it gently until we get to about a 16:8. That’s really where I like to have most people end up. I think it’s totally doable, but it’s one of those things I think humans, in general, male or female, you jump in too aggressively, too fast. They’ll do it once and then they’ll never come back to it again. Simply, you just have to build up tolerance like any tool. You wouldn’t go into the gym and then just go lift the heaviest kettlebell or go and squat the most plates. You slowly increase your tolerance and your capacity for that resistance. The same is true for fasting. You want to slowly increase your tolerance and your resistance to some of the temptations that fasting can have.
Ari: Absolutely. On fasting, this is a controversial topic for many reasons, and there’s lots of nuances here. You’ve addressed the unique female physiology aspect of it, but there’s also some people who argue the negatives of especially prolonged fasting likely outweigh the positives, especially in terms of loss of lean muscle mass. Some people have argued that you can really get all of the same benefits from, for example, just a nightly 14- or 16-hour fasting window done on a daily basis or do protein-sparing modified fast or something like that so you don’t lose lots of lean muscle mass during fast. What is your take on the benefits versus risks of long-term fasting, like multi-day fast with no calories, versus how much of those benefits do you think people are getting just from having a nightly 16-hour fasting window?
Dr. Estima: I think it’s just a matter of amplitude. Again, I think it also comes back to your goal. If your goal is to repair the gut, then you want to go as long as you can without putting anything in there in order for your gut to have the ability to heal itself. If your goal is weight loss, you can get away with doing a 16:8 and your weight loss will be slow and steady over time. I’ve heard a lot of these arguments, and I think a lot of them are theoretical, I think that we don’t know the answer. What I can tell you from my own experience and from my clinical observations, is that when we’re thinking about muscles, in particular, we want to think about how we can always be driving something called muscle protein synthesis or MPS, because I don’t want to say muscle protein synthesis four million times in this, so I’ll just say MPS. There’s two ways that we can drive MPS. One is through the diet. There’s a chemical stimulus. That comes through consuming proteins. Typically, it takes about 20 to 25 grams of protein that you’re consuming, whether that’s powder form, it’s meats, it’s pea protein, whatever it is, you have to have about 20 to 25 grams of good quality protein. Actually, I’ll correct that, it’s 2 to 2.5 grams of leucine that you’re actually looking for. In a vegan protein like a rice protein or pea protein, you’re actually going to require a little bit more than 20 to 25 grams. You might require 35, maybe 40 grams because they’re not as leucine-rich as more animal sources are. You need that leucine. She’s the for woman, as I like to call her, that starts that process of synthesizing new muscle. That’s one way that you can do it. The other–
Ari: I love how you’ve anthropomorphized amino acids, by the way.
Dr. Estima: Yes. She hit the she. [laughs]
Ari: Leucine is definitely a she.
Dr. Estima: Leucine is a she. [laughs]
Ari: Not the prettiest name I’ve ever heard for a woman but it works.
Dr. Estima: If I had a daughter, her name would be– no.
Dr. Estima: That would actually be a pretty good name for a girl, actually.
Ari: It’s not that bad, leucine. It’s better than tryptophan, I’ll tell you that.
Dr. Estima: [laughs] Yes, agreed. That’s one way that you can do it. The other way that you can do it is through a mechanical stimulus, through resistance training. I will state my bias here I have a huge bias for lifting heavy weights and for resistance training. I have a bias for fasting and the ketogenic diet, but I also think that those things need to be tweaked and modified over the course of a woman’s life and particularly over the course of her menstrual cycle. If you are engaging in a long-term fast, as long as there is that mechanical stimulus, as long as you are training every day, you can still both maintain the muscle and I would argue, continue to gain muscle while you’re fasting. In the spirit of honesty and transparency, when I have done long-term fast, my muscles look flat. I get the pump working out but they’re not as jacked as when I’ve had a post-meal of whatever it is, like protein and carbs or whatever, and they’re filled up with that glycogen.
The importance of muscles
Ari: This might be a quick digression, and sorry to interrupt your flow, but maybe worth addressing the fact that there are a lot of women out there who might not resonate with where you’re speaking from right now, in the sense that a lot of women don’t perceive it as a good thing to be muscular and are worried about maybe being too big and bulky and having too many muscles. They might say, “Oh, what’s the problem with having flat-looking muscles? Why isn’t that a good thing? I want to be more slender.” These are how a lot of women perceive–
Dr. Estima: Let me clarify what I meant there. I’m not talking about looking like She-Hulk. Even if I wanted to, I don’t have the amount of testosterone to be able to drive that. This is a persistent myth that I don’t know where it comes from. People think that they need to be lifting two-pound weights in order to look toned. This is a word I hear, toned, a lot. It makes no sense because tone is actually a nervous system. When we think about whether or not you have tone, this is a nervous system qualifier. I’m not talking about looking like a bodybuilder because when we think about those bodybuilders, they are most likely taking exogenous testosterone and other proxies to build them up. A woman cannot naturally build herself up to look like the Hulk. This is a thing that I continue to bump up against and I’m so glad that you stopped me because sometimes I just forget to address that. A woman, as we age, the number one predictor, when we think about a woman moving into menopause and even beyond menopause 60, 70s, 80s, the number one way that we can predict her independence is whether or not she can get out of a chair unassisted. What is required for her to get out of a chair unassisted. When I say unassisted, that’s not holding on to a table or pushing herself up from the chair. It requires glute strength, it requires quadricep strength and hamstrings.
When we think about the muscles that tend to atrophy from modern life, of course, we are not walking in the way that we should, our hamstrings and our glutes tend to– Or I should say, in particular, the glutes are long and weak. We literally sit on them all day long and they are the major extensors of the hip. It is important for women to be squatting at least their own bodyweight but preferably heavier than that. For our upper body strength, the strength in our appendicular musculature, the shoulders in particular and the back is what I am referring to here. I cannot tell you how many times I get on an airplane and maybe not now because there’s nothing going on in terms of flights, but in the pre-corona world where you would have women at the– I would see them all the time asking men, “Can you put my carry-on in the overhead?” Its like, “Guys, that’s 20 pounds. You should be able to lift 20 pounds,” or ladies, you should be able to lift 20 pounds over your head. This is not only for when we take a look at longevity and your ability to be independent as you age but let’s just be honest, nice shoulders and nice round glutes are aesthetically very pleasing. If you are concerned with aging well, being able to play with your kids and your grandkids, being able to travel and being able to carry your own luggage. Even if your luggage is– You should be able to lug a 50 or 60-pound luggage. That should be a no brainer for you. Then also if I can appeal to your longevity mind, let me just appeal to you want to have a nice butt.
Ari: Yes. [laughs] I was a trainer for many years in my early ’20s, mid-’20s and I was notorious. Most of my clients were women, and I was notorious for having them lift really heavy weights. Other women would walk by and be like, “Oh my God, I can’t believe how strong you are,” to my clients. I would tell my clients always, “I know you think you want to look toned, you’re afraid of heavy weights, the reality is muscle is not built that easy and what you mean by toned is you got to understand there’s only two things you can do to modify the way your body looks; you can lose fat or you can gain muscle. The look that you are trying to achieve, almost invariably for pretty much everybody, involves usually losing fat and gaining muscle. The lifting of 2-pound, 5-pound dumbbells is not an efficient way of doing either of those two things. You want to gain muscle you got to lift heavy stuff. If you want to lose fat, it’s a combination of that plus diet and other lifestyle modifications.”
Dr. Estima: As we age, we also become more resistant. We become more this anabolic resistance. We have to continue both from the diet but also in our training regimen to be lifting heavy to continue that mechanical signal to the muscle and then we also want to be thinking about maintaining our protein or increasing our protein even as we age as well to circumvent the sarcopenic obesity that we see too in the older population.
Ari: Worth segwaying into that. Sarcopenic obesity, explain what that is and explain why sarcopenia is so important. I think this is such an important thing and very few people are even aware of it and how does it tie into what we were just talking about with lifting heavy things and muscle mass?
Dr. Estima: Sarcopenic obesity really is loss of muscle essentially over time. As we age, we become more resist– If you were to never train and you were to eat the same amount of protein every single day for the rest of your life, over time, your muscles will become more resistant to that muscle protein synthesis that we were talking about. You would need to increase your protein consumption in order to continue to maintain the muscle mass that you have and to continue to grow new muscle. That would be the most basic explanation of what it is. The net, net result is that because you are losing muscle and muscle is so intimately tied to bone density, you will also begin to lose bone density and then you will become relatively more– The amount of fat that you have is going to be relatively more than what it would be if you had more lean muscle mass. It is important for us to be considering weight training, and as you were saying, weight training heavily, lifting heavy weights and not being afraid of that because you’re not going to turn into the Hulk, but also, as–
Ari: I wish I would have turned into the Hulk a long time ago if that was the case. I wish it was easy to gain–
Dr. Estima: I would be She-Hulk. I lift heavy stuff, but because of the amount of testosterone that I have, it’s just not possible for me. As you said, putting on muscle, you can’t put on 5 pounds of muscle in– It takes a lot of time to put on 5 pounds of pure muscle. You have to do a lot of work and you have to be consistent over many months. I would say that there’s that. The other thing to consider, like I mentioned, is that your muscles and your bones are intimately connected with each other. Of course, we know that your muscles attach into your bones, but as you decrease your muscle mass, you will also invariably and predictably decrease your bone density as well. This is, again, when we’re thinking about independence, number one reason why most older women, but I think this is true for men, but I know that for females, is in the wintertime here in Toronto or on the East Coast, there’s ice, there’s snow, slipping and falling on your hip and not having the hip fracturing. That is the number one reason of loss of independence for women that cause them to go into nursing homes or requiring care. We want–
Ari: Death, loss of life. When we talk about people growing old and dying of “natural causes”, it’s often like that. It’s often just frailty and sarcopenia.
Dr. Estima: Yes, yes.
Ari: I want to talk to you about the consequences of long-term calorie restriction. What does this look like? A lot of women out there are just in– They want to be lean and so they’re just in perpetual diet mode. They’re constantly restricting calories to some degree or another depending on fluctuations in willpower over periods of time, but over very long periods of time, this happens. What are the consequences of this and maybe especially related to the fact that very few women are doing this resistance exercise in the way that you were talking about?
Dr. Estima: I think there’s a couple of things. One, I am not a big fan of caloric restriction over the long-term. I think that we need to like anything. It’s nuanced, but I think that there needs to be fluctuations in both the caloric intake that we have throughout the month as well as the macronutrient composition of the diet. What we know about caloric restriction, particularly in females, and some of this is taken from, I will quote, “some rodent studies”, which I’ll happily give you the links for for the show notes, but I’ve also seen this in the clinic as well. Couple things that we see. When we have women who are on long-term caloric restriction– This can be as little as 20% caloric restriction, meaning that you are restricting your calories by 20%. If you’re supposed to be– If you have a BMR of 2,300 calories, 20% of that would be– Let me see if I can do math off the top of my head here, or 2,200 calories, [chuckles] it’s easier.
It would be a 400 calorie restriction. We have this caloric restriction, as little as 20% can cause menstrual cycle irregularities. It can cause the ovaries to shrink or masculinize. It can cause amenorrhea, dysmenorrhea. It can also cause changes in brain function. What we see, and this is something that my females tell me all the time when they’ve been trying to eat a 1,200 calorie diet for years, is that when they are adhering to that, their sleep patterns become irregular. They are now waking up– They have trouble initiating sleep, but they also have, in particular, maintaining their sleep. This is because there is these neurons called the hypercritic neurons. They become over-activated, and we see this in rodent studies as well, where rodents tend to be nocturnal, meaning that they sleep through the day and they’re more active at night. During the day, they are much more active. They are not sleeping in the way that they should and part of the–
Ari: If they’re calorie-restricted.
Dr. Estima: Yes, if they’re calorie-restricted. Exactly. The thinking around this, taking an evolutionary lens to, is that the female– In general, we are generally more defensive of our fat stores because we have to have this thing called pregnancy and childbirth and child-rearing and breastfeeding and all those things that go along with it. When there is a restriction in calories over the long-term, the thinking around this is that we will start to have disturbances in our sleep in order to forage over a larger perimeter of area to find food. We see that. In the road in study specifically, we see things like learning is amplified, it’s higher. You might think initially that that’s a good thing. Like, “Oh, she’s being able to learn faster.” What they would do is they would put rodents in mazes and they would have food at the end of it and they will be able to figure it out, but that’s because they’re starving. It’s because they’re trying to figure things out so that they can find food. Long-term caloric restriction, not a big fan of it, just like I’m not a big fan of long-term, like just being on keto all the time. I don’t think that that’s appropriate either. Then, we can maybe foray into that internet forest today as well. I think that caloric restriction is appropriate. There are certain times of your cycle where you can play around with caloric restriction and fasting, but in general, you want to be cycling that. I don’t think that it’s appropriate for women to be doing that long-term at all.
Ari: If that’s the case, you are an advocate of restricted feeding windows and also an advocate of playing around with fast of various durations and different variations of those things. It’s not–
Dr. Estima: As it honors your circadian biology.
Ari: Yes. It’s not that you’re opposed to caloric restriction period you’re posted long-term calorie restriction. Does that also mean that let’s say someone doing a four-week or six-week or eight-week intensive fat loss regimen is also acceptable and then they go back into weight maintenance mode at that point? Is that something that you are an advocate of?
Dr. Estima: I hate to answer this way, but it depends. Let’s use an example like the obese woman that we were talking about before. I think it’s important for her to be able to establish metabolic flexibility, to be able to switch from being glycolytic or using glucose as her primary substrate for energy production, to be able to use free fatty acids and ketone bodies. I think that that’s very important and that does on average. When we’re thinking about becoming fat-adapted, the literature suggests that that’s somewhere between six to eight weeks, and I would say that that’s also true. I’d also say that that’s true clinically as well. Depending on the person’s history, it takes them about six weeks to really get the groove of that and to be able to flex that new muscle, if you will, to be able to switch into being more lipolytic or being able to use fat as their primary energy versus being glycolytic. Again, to your point, I do think that after that skill or that tool has been learned, I think that it is not appropriate for them to be eating a very strict, especially if it’s a woman, to be eating a carbohydrate-restricted diet or I should say a ketogenic diet forever. I think that there are ways that we can cycle that through her menstrual cycle, whether she’s perimenopausal and what phase and perimenopause she’s in, and even when she’s menopausal, I think that there’s ways that you can cycle that in order to honor the cadence and the rhythm of your hormonal landscape.
Balancing the ketogenic diet for optimal fat loss for women
Ari: You’ve alluded to keto a couple of times now. You are a big advocate of ketosis, but you’re not a big advocate of being on a keto diet all the time. This is an important distinction because I’ve had some people on the podcast in some cases created quite a lot of controversy because I’ve been notable for saying, “You probably don’t want to be on a keto diet all the time, long-term.” I’ve seen way too many anecdotes of people crashing and experiencing negative results of that, but I’m also totally fine with short-term and cycling of ketogenic diets. I’ve had some people on the podcast who, for example, argue that the keto diet is our ancestral diet. All of our hunter-gatherer ancestors were keto all the time. That’s the way that our biology is meant to operate, period, any deviation from that carbohydrates are sort of fundamentally not aligned with our biology. We should be keto all the time. Some people have been convinced of that narrative. I definitely do not agree with that. What is your take on the keto landscape as an advocate of keto diets, but not long-term keto?
Dr. Estima: I’ve run an online nutrition program now that is the Ketogenic Diet going on four years now. I am a huge advocate for, like I said, learning that new skill to become metabolically flexible, to be able to dip in to being ketogenic, meaning the ability to generate ketones or ketone bodies whenever you need to. I also will say that it is a cornerstone of– I think it is a useful life skill to be able to eat a carb appropriate diet. Now, that doesn’t always mean that you are going to be counting your carbs and eating under 20 grams of carbohydrates a day. I don’t think that that’s appropriate for the long-term. I think it’s going to destroy your neurotransmitters. I think you’re not going to be able to sustain it you’re going to fall off. Then like I was saying with fasting before, you walk into a gym and if all you’re going to do is go to the heaviest kettlebell and punch out the heaviest front squat or whatever you’re doing, you’re not going to be able to do it because that muscle isn’t developed.
You can’t just jump into a seven-day fast because you don’t have the skill yet. You want to be thinking about, with a ketogenic diet, developing the skill and then playing with it, coming in and out of it over time. This is particularly true for women. The program that I run is called the Estima Diet because I am not creative and I just named it after myself, but what we do is like the first step is nutritional ketosis. Then when you are a female, we understand what your hormonal status is, and then we cycle you through a ketogenic diet based on where you are in your menstrual cycle because like we’ve been talking about, every single day of the month, you have a different hormonal profile.
You are going to be able to tolerate more aggressive types of fasts, you are going to be able to tolerate more aggressive carb-restricted macronutrient composition at certain times of the month. Then there’s other times of the month, particularly in the second half of your cycle, when your progesterone levels are increasing, so your appetite is being stimulated, your bowel movements are slowing down. It’s harder to fast when you have a hormone that is it’s involved in progesterone, pro-gestation, pro-pregnancy. That is the hormone that is involved in, whether you want it or not, in maintaining a pregnancy. It’s waiting, it’s trying to develop that endometrial lining to receive that fertilized egg and it is going to stimulate your appetite.
Even in the amount of calories that you should be taking in, in that second phase of your cycle, needs to change as well. I advocate for uptaking your caloric intake, particularly in the week right before your period, like week four, by about 10% or 15%. Over the long-term, I am not a fan of restricting carbohydrates indefinitely. There needs to be an up and down. Most women that I’ve spoken to have tried keto– At this point, keto is very much mainstream. When I started, I had people telling me that I was like, I don’t know if we could swear on this podcast, but it’s like bat shit crazy.
Now, most everybody has tried it but what the pattern that I have observed is people fall off of it around two or three weeks because that satiety signal is just going bananas and people will fall off it and then be on just carbs. The short answer is not a fan of being in ketosis all the time. I think as a woman, because our biological function is reproduction, we are always naturally going to need a little bit more of a bump in fat and we are– You can see this between men and women. We tend to have a higher body fat than men do. We need that extra padding to be able to carry through a pregnancy and even just to have the energetic capacity to build up the endometrial lining, which happens whether or not you’re– It happens every month. You’re building up that endometrial lining every single month. We will always require a little bit more calories and we’re always going to be a little bit more defensive of our fat stores. I don’t think that we should be in ketosis all the time.
Ari: Training is another subject. We covered it in the interview that’s going to air as part of the Superhuman Energy Summit.
Dr. Estima: Great name by the way. I love the name.
Ari: Thank you. I came up with it myself. That’s going to air. We don’t have time to address it in full right now. I want to also make sure that this interview is like covering different stuff than what we covered in that other interview. We have a few minutes left. What I want to do is you’ve covered a few really critical topics. Time restricted eating, you’ve mentioned circadian rhythm. You’ve mentioned lifting heavy. You mentioned the keto diet. You’ve covered this with a lot of nuance and complexity, as far as giving the landscape of how this is, but some people might be left wondering, how do I actually apply this? What’s the best way for me to do this now? Let’s take a hypothetical person. Let’s say 45 years old, not standard American diet, not sedentary. They’re doing some bit of exercise three or four times a week. They’re not obese, but they’re a little bit overweight, and they already know the basics of healthy eating. What would be, if you could say your top three or four things for them to start experimenting with right now, what would be those top three or four things?
Dr. Estima: The top three or four things would be, one, experimenting with a ketogenic diet in the first two weeks of her cycle. That would be the period– like her bleed week and the week before ovulation. Playing around with restricting her carbohydrates, particularly in the week of her period, that’s actually one of the best weeks. Out of all four weeks, that’s my favorite one because progesterone has now reset and estrogen, which is also a trophic factor, is also low as well. I like the keto diet in that first week. I would start playing with, if she’s working out call it three times a week, I would start, and maybe she’s doing some resistance training, maybe some calisthenics, I would start thinking about how she can be lifting heavier.
Whether that is investing in heavy weights, like I said, even if you want it to become She-Hulk, it is very hard because of our testosterone levels. I would start doing full-body exercises. Things like Sumo squats, I love things like burpees and I love split lunges. I also like, and I’ll put in a little caveat here. We talked about this in the other interview, but I would also just want to mention it here because it’s so important to be thinking about exercises that expand your– You’re not just doing flection and extension exercises all the time, which is what we see. I see it all the time. Even just thinking of any cardio machine, it’s all just fluxion and extension. We want to be thinking about abduction and adduction. We want to be thinking about moving away and crossing the midline. This is so important again for those appendicular muscles that we were talking about, the glutes, the shoulders, and the axial muscles in the spine as well and the muscles that stabilize the shoulder and the rotator cuff. This type of coronal plane or AD and AB duction type of exercises are so good for brain health.
Things like stepping out to the side and doing squats, curtsy squats, anything where your feet are moving out and in or your arms are moving out an end. That’s so important. I would be thinking about that. Another thing that I think is important, and I would say that this is true for men and women, is thinking about how we can be improving our non-exercise activity thermogenesis or NEAT. We all have become more exercise specialists. We sit at the desk for eight hours and then we go to CrossFit or we go to SoulCycle for an hour and we punch out this super-specialized type of movement. We’re not actually getting a lot of generalized movement through the day.
That is really– I’m going to be unpopular for saying this because it’s not sexy, but like honestly, getting up and doing like a 10- or 15-minute walk or 20-minute walk or finding ways gardening or moving or cleaning your house. These are other ways that we can think about– If she’s thinking about weight loss, this is a really easy way for you to be thinking about increasing your caloric expenditure every single day. The technical term is NEAT, but it’s just generalized movement rather than thinking, like, “I got to get to another class.” Don’t think about that. Think about how you can move more naturally in the environment that you already live in. Then the third thing would be really prioritizing sleep.
That is something that I think people know that they should be doing and they don’t. I think that this is a cultural disease that we all bear where there’s this fetishizing of being able to live on four hours of sleep. I did pull an all nighter and look at me. When we think about weight loss, you want to lose weight, just sleep eight hours a night, like you’re going to reduce your insulin levels, you’re going to become more insulin sensitive. You’re going be able to– One of the most toxic things to your brain is sleep deprivation. When you think about willpower, the area of your brain that’s involved in regulating your emotional centers is offline, good luck, good luck with that. There’s no such thing as willpower when you’re not sleeping well. Just really honoring your circadian biology and your rhythms through proper sleep. Eight hours is what I insist on for myself and for my clients, which means that you’re probably in bed for about nine hours. It takes a little bit of time to fall asleep and get out of bed and wake up in the morning. That’d be my top four. Circadian rhythm, more general activity, try keto on the first half of your cycle.
Ari: Love it. I couldn’t agree more. I want to say on a personal note, again, such a pleasure chatting with you. I love that I can just throw out random questions to you and keep you on your toes.
Dr. Estima: I love that too.
Ari: I love your answers. I know there’s a whole bunch of other topics we could talk about, the training and how that connects to the menstrual cycle, menopause and perimenopause, and how that changes things, your wealth of information on female physiology, in particular. I almost want to have you on every month or two because they’re, as I’m sure you know. This is maybe not super polite of me to say, but there are some people out there who you talk to for an hour or two and you know that’s pretty much, that’s their whole shtick and you’ve covered everything they know and there’s no real point in interviewing them again because you’ve already got what’s there. Then there are other people who are constantly staying on the cutting edge and reading the latest literature and experimenting and are always learning new stuff and always have new stuff to share that they want to teach to the world and how they’re taking the science and applying it in the real world and connecting the dots and turning it into ways of experimenting to optimize physiology. I know you’re in that category. I almost want to just have you on every month or two or something to stay on the cutting edge of female physiology since you’re exploring that so deeply.
Dr. Estima: You just have to say the word, Ari, and I’m there. I would love to. I have so much fun with you. Again, I’ve enjoyed this immensely. I would love to come back again.
Ari: Me too. Last thing, and then I have to run to the next interview, for people listening who love what you’re talking about, who want to follow your work and get more from you. Where’s the best place to do that?
Dr. Estima: You can find me. The website would be drstephanieestima.com, which I’ll give to you for the show notes. I’m pretty active on Instagram. I’m always putting some geeky magic stuff out there as well. I sometimes do TikTok videos and TikTok dances.
Ari: Beautiful. Thank you so much, my friend. Such a pleasure connecting with you. I look forward to the next one.
Dr. Estima: Me too. Thank you so much.
The difference between men and women when it comes to weight loss and exercise (4:25)
The best fasting guidelines for women (14:00)
The importance of muscles (28:03)
Balancing the ketogenic diet for optimal fat loss for women (43:50)