Protein, Blood Sugar, and PCOS: Nutrition for Fertility (Episode 607)

Full Transcript: Episode 607

Lisa Hendrickson-Jack:

Happy new year. It’s officially 2026 and I want to welcome you back to the Fertility Friday podcast. I’m really excited for this new year. And you know what? I thought, what better way to kick off the new year than with this in-depth episode with Lily Nichols, where we dive into the importance of nutrition for fertility. We get into a lot of really interesting data in this episode. We go into PCOS as a case study to showcase why blood sugar balance, macronutrient balance, and micronutrients matter for fertility. We talk about the issue of undereating protein because this is something that is very, very consistent. Undereating protein consistently is associated with unbalanced hormones and menstrual cycle irregularities. And so we talk about what the research has to say about how higher protein approaches do result in better outcomes for women not only with PCOS but overall.

And that is truly only the tip of the iceberg. For those of you who don’t know Lily, Lily Nichols is a registered dietitian nutritionist, certified diabetes educator, researcher, and author with a passion for evidence-based nutrition. Her work is known for being research focused, thorough, and sensible. She is the founder of the Institute for Prenatal Nutrition, the co-founder of the Women’s Health Nutrition Academy, and of course the author of three books, Real Food for Fertility, which we wrote together, Real Food for Pregnancy and Real Food for Gestational Diabetes. So without further ado, let’s go ahead and dive into today’s episode with Lily Nichols.

And I’m excited to be back again with Lily Nichols for our part two throwdown on Real Food for Fertility. Welcome back.

Lily Nichols:

Happy to be here. Let’s do this.

Lisa Hendrickson-Jack:

All right. Well, so in our first episode together, I had a ton of fun. We were able to really talk a little bit more about the process of writing and share some behind the scenes. But in today’s episode, we wanted to get into some of the nitty-gritty details and especially some of the details that you went to in your sections of the book. So yeah, we have on the agenda today to talk a little bit about PCOS and to talk a little bit about protein because you found some really interesting data. So I think I’ll just ask kind of a general question to get us started. I know we got into a little bit of this in our first episode together, but share a little bit about what you found about the significance of protein in fertility and how it relates especially to women with PCOS.

Lily Nichols:

Well, I’ve long been a proponent of people consuming enough protein for many reasons, even outside of like the childbearing and pre-childbearing years, just because of its effect on our satiety and blood sugar regulation. It just makes a very tangible difference when people get enough protein and so many people I find are undereating. I may be a little bit naive because I mean I’m coming at it from the assumption that protein is important but I don’t know how far off the recommendations are for supporting optimal fertility compared to what our recommended dietary allowances are. Whereas like in pregnancy, it’s like I have like specific data to pull from where they’ve like studied pregnant women and this is optimal in fertility like I alluded to in our last interview is a little bit trickier to like nail down. So I went at it from a couple of different angles. Looking at the like blood sugar perspective and how that affects fertility. Obviously there’s a little bit of carryover on protein there. Looking at it from the standpoint of like ovulatory function. What have we observed in some of these very large trials or large observational studies? What are we observing in the women who tend to eat more protein or the women who are in like an intervention study assigned to a higher protein intake? And then looking at it a little bit sort of mechanistically from what’s going on with individual amino acids and how that affects the menstrual cycle, ovulation, conception, and early embryogenesis. So looking at it from like all of those angles as a whole I could say without getting into the nitty-gritty at least not yet is that optimal protein intake for supporting fertility, reproductive hormone levels like menstrual cycle function and supporting optimal conception and supporting optimal intake of micronutrient levels — we need more protein than the standard recommendation. And actually, it kind of aligns pretty closely with the data that we have on pregnancy. So, like outside of pregnancy, leading up to pregnancy, supporting fertility, you probably want to aim for at a minimum the protein levels I’m recommending for early pregnancy in, you know, my other book, Real Food for Pregnancy. And for women who are more physically active and they have higher protein turnover from muscle repair and like supporting their connective tissue and everything, they need to aim even higher for protein. So that was like the major takeaway on the PCOS side of things and we can get into more of the specifics. The most successful dietary intervention trials for PCOS were in those that modified the macronutrient ratios in a way that they were eating more protein and specifically usually erring towards more protein and fat and less carbohydrates or at the very least like better quality low glycemic carbohydrates.

Lisa Hendrickson-Jack:

Well, so I think a lot of our listeners are familiar with PCOS, but maybe share a little bit about the kind of metabolic issues that arise with PCOS, why with PCOS — for I would say especially the more classic types of PCOS — why the dietary change and the focus on protein would be so important.

Lily Nichols:

Yeah. Well, I mean, you and I both teamed up on writing the PCOS chapter, so you could probably go into even more of the specifics on some of this stuff, but to highlight one of the areas that I was really focusing on is the insulin resistance component, which actually ties into the other metabolic components that are also going on with PCOS. So, like it’s all related, but I tend to really zero in on this one. I mean the majority of PCOS cases involve some level of insulin resistance. Anywhere from like 50 to 70% of women with PCOS are insulin resistant to some degree. And depending on which of the phenotypes — which of the four phenotypes you have, A, B, C, or D — levels of insulin resistance can be different or prevalence of insulin resistance can be different among those phenotypes. So, the reason that this matters is like you have insulin receptors all throughout your body, including on the ovaries. And if our bodies are exposed to high levels of insulin, day in and day out, meal after meal, for a really long time, our body starts to become insulin resistant. It stops responding like it normally would to insulin. And then the body has to pump out like even more insulin to get the same metabolic effect, the same like blood sugar lowering effect that you see typically when insulin levels are elevated. And when we can bring insulin levels down, which we usually need to do by way of not spiking the blood sugar as frequently and as high as is typical so that we’re not like poking the bear, so to speak. Then over time, we’re not only lowering insulin levels, but we’re also lowering levels of insulin resistance. And it’s really tricky to bring blood sugar levels down without consuming enough protein. If you’re looking at like how different macronutrients affect your blood sugar levels and thus also your insulin levels because it’s like blood sugar goes up first and then the insulin like they always go hand in hand. By and large carbohydrates are the biggest macronutrient that’s going to spike your blood sugar. Protein and fat will trigger a fairly small release of insulin — protein a little bit more than carbohydrate. Although in people who are not diabetic, the blood sugar surge and insulin surge caused by protein is like really, really, really small. And even in people with diabetes, it’s like nothing like exponentially less compared to what’s triggered by carbohydrate consumption. So if we can get the levels of insulin and the levels of insulin resistance down, you start to see the other metabolic issues going on with PCOS also improve. You tend to see chronic inflammation and oxidative stress come down. You start to see androgen levels come down as well. Like it’s all related. So that’s why I tend to like focus from that angle first because it is effective. It just works.

Lisa Hendrickson-Jack:

Well, and when you talk about, let’s say, eating like more protein, I think that a lot of women might think, so I have to eat more food. Maybe what made me think of this also is that we had one of our advanced reviewers who made a comment that one of her biggest takeaways was the kind of plate method, the reorganizing of the macros. And it was one of those things where it’s like, especially you’ve been talking about this in your work for so long. I mean, you were doing this in the community and seeing such great results. And it seems after you learn about the plate method, it seems so like, oh, of course, you know, but I don’t know, I just thought about that review and thought like, okay, well, wow, that was one of her biggest takeaways. So, maybe share just I suppose for anyone who’s like, oh, is she telling me I have to eat a whole bunch more food. How does this work?

Lily Nichols:

Well, you can eat a whole bunch more food depending on what the food is. So, that depends. You might actually be able to eat a whole bunch more food. You don’t necessarily have to, and your satiety will probably shift a little bit as you pay attention a little more to your macronutrient ratios. So, it’s funny. I find my work is split between like this really in-depth detailed scientific stuff and then also like the sort of basic educational takeaways like the plate method like the plate method has been used for decades by lots of different practitioners. I think my plate method like is a little more fine-tuned by macronutrient groups versus like food groups from the typical like government ones to really kind of hone it in a little more detail. But it’s really quite simple when we shift the ratios of our macronutrients, our fats, carbohydrates, and protein toward a type of plate that is not so heavy in carbohydrates, we’re going to improve our blood sugar and insulin levels. So typical way that a lot of at least Americans will eat is a very like carb-centric meal. It’s based around pasta or potatoes or rice or bread. It’s just really heavy on the carbohydrates. And then the other components of the meal are just kind of like extras. You have like oh a little bit of protein in there like a few meatballs on the pasta and maybe there’s like a few vegetables mixed into the pasta sauce but really at the end of the day you have a huge plate of carbs and if we can shift that towards like a — I’ll just use the pasta example because that’s the one I came up with — a small portion of pasta taking up maybe a quarter of the plate, a larger portion of meatballs. You actually get a substantial filling portion of protein. For most women that’s probably going to be — well, it depends on your size and your activity levels — but like 3 ounces at minimum, maybe four, five, even 6 ounces of protein for somebody who’s more active. And then like a large salad or a large portion of like cooked broccoli or green beans or something on the side. Or maybe you get real fancy and you do like zucchini noodles or something in place of part of the pasta and kind of work it into the meal itself. The effect of that on your blood sugar and insulin levels is like a completely different animal from the plate that was really just all carbs with a couple meatballs and like a little veggies in the sauce. You don’t have nearly the carbohydrate loads. You don’t get nearly the blood sugar or insulin spike. Your satiety levels are so much better because protein is so filling and also the fiber from the vegetables is so filling. And so, yeah, you feel more satisfied for longer, but without the crazy blood sugar roller coaster that would follow a typical carbohydrate-rich meal. And for women with PCOS, especially, I would say uncontrolled PCOS, you know, when we’re still seeing the effect on the menstrual cycle, which is primarily delayed ovulation leading to a really long cycle. I’ve worked with a number of clients who when they’re in that season where before they’re able to get the insulin resistance under control and have the cycle normalized, they might be seeing cycles that are 45 days or 60 days. We give a couple of examples in the book where the cycle was well over 60 days. So I mean the big result that a woman with PCOS is looking for in general is to have that cycle normalize often also to improve their androgen levels so that a lot of women are suffering from hirsutism, acne. So reducing those androgen levels and things like that and obviously normalizing the cycle but more particularly for women who are trying to conceive like they also want to conceive.

Lisa Hendrickson-Jack:

So, you shared some really interesting research on how dietary interventions have had a positive impact on some of these markers. Did you want to talk a little bit about that?

Lily Nichols:

Yeah, I could go into a couple of study examples that I give in the book. PCOS, like when you’re looking at studies done on fertility in women specifically, I’d say the majority of them that we have is actually on women with PCOS. There’s quite a few out there with a fairly wide array of dietary interventions. Most of them focus on shifting energy intake like calorie-restricted diet and then some focus more on shifting the macronutrient intake and so you have like an array of like super low carb like ketogenic style diets to modifying the carbohydrate quality and like shifting the protein up. So I can go into a couple of those. I will say that as a whole, even in studies where you just modestly reduce the carbohydrate intake, even like 10, 15%, you see significant improvement in a lot of different parameters that we’re worried about with PCOS. Here’s one example that I think is worth mentioning. Women with PCOS were given one of two diets, the standard diet or high protein diet. And the high protein group had naturally higher protein intake, but they also had a lower carbohydrate intake. So they had 113 grams of protein per day and 155 grams of carbohydrates versus the standard diet had 78 grams of protein per day and 265 grams of carbohydrates. And in the women in the high protein group, they experienced greater weight loss of 17 lbs versus 7 lbs. They had a reduction in body fat and they had significantly improved blood sugar levels after six months on the diet. In other trials that have done more strictly low carb, like some of the ones that have done a ketogenic diet, have seen, I would say, even greater improvement. So, there’s one study where they did a moderate protein ketogenic diet. So, they kept carbs at 20 grams of carbohydrates per day. That’s quite strict, but that’s at ketogenic levels. And this diet was followed for 12 weeks. And at the end of that time, clients lost an average of 21 pounds, 18 pounds of which was body fat. And that’s important because sometimes you put people on dietary interventions and they lose weight, but they’re losing muscle mass. 18 out of 21 pounds was body fat. So that’s showing significantly improved metabolic health. It helped normalize their sex hormone profiles. It significantly improved blood sugar and insulin levels, markers of insulin resistance, and blood lipids. So, I could go into more. There are plenty more dietary intervention trials at different levels of carbs or protein or whatever, but as a whole, I think the takeaway is sort of shifting the balance to slightly less carbohydrates and better quality carbohydrates. So, less processed, less refined carbohydrates, more protein, and fearing fat less than is the standard. The degree to which you’re going to need to make those changes, like how strictly low carb and how much more protein you need to go, probably depends on your individual case and like the severity of insulin resistance that is present because not everybody needs to go keto necessarily. Even like a moderate shift can improve things. But in some cases that are more severe or more resistant to treatment or ones where like say your insulin resistance levels are at levels where your doctor wants to put you on medication like metformin or something, you might want to err on the even lower carb, even higher protein route if avoiding medication is one of your goals.

Lisa Hendrickson-Jack:

Well, you know, interestingly, I was actually talking to my husband yesterday. Because of what I do, he always finds himself in conversations with women and he mentioned a friend of his has PCOS. And like a lot of women with PCOS, she was just told to lose weight. And so, what’s really helpful even about what you just shared with us is that in the second study you mentioned, the participants did lose weight as an effect of the diet. But it’s more nuanced than that. We’re not just saying flat like well as the only solution just to lose weight. We’re actually going a little bit deeper into what is the root of this issue, the insulin resistance, and talking about how to control the blood sugar and then as a byproduct of that as you improve metabolic health you’re seeing these benefits. I could just imagine for his friend to hear this information it’s so much more helpful because then she actually has an understanding of what the problem is. And to kind of put it out there as well, I mean, in our PCOS chapter, we talk quite a bit about how insulin disrupts ovulatory function. So why this is actually having that negative effect so that you really understand why it’s so crucial to focus on that piece of it because it’s when the insulin is out of control that causes this cascade of events including the increased androgens that really does end up disrupting ovulatory function. Once you are able to control that insulin output and your body’s response to it and you’re able to kind of at least put out the fire so to speak then you can start to see those improvements in the overall menstrual cycle. So to shift to another question for you, you had mentioned about different types of studies and you had said that some of the studies are looking at shifting that macronutrient ratio so that we’re reducing — basically when you increase the protein you crowd out some of the carbohydrates. So you don’t end up eating less food, you’re just shifting the way you’re eating. But you also mentioned that some of the intervention studies are looking at reducing calories because again a lot of women are hearing that they need to just lose weight. So maybe share a little bit about that and the kind of nuance there and the different approach that we’re taking because we didn’t jump in and say you should restrict your calories to lose weight, right?

Lily Nichols:

Yeah, we don’t. I was actually at a conference recently, the Metabolic Health Summit, and Dr. Ben Bikman was speaking. Many people know him. He’s like a metabolic health researcher often specifically looking at fat and insulin. And one of his comments that I found really poignant because I had never thought of it in this way is that one of the confounding variables that you have between studies that are low calorie — it’s like high carb, low fat but low calorie versus low carb — is both of these interventions are what he terms a low insulin diet. Both of them are reducing insulin levels. They’re doing it by different means. So with an energy deficit, low calorie, you’re going to lower insulin levels. With a low carbohydrate diet, even if it’s higher calorie or sufficient calories, you’re going to lower insulin levels. Now, still often times the low carbohydrate diet outperforms the low calorie diet in these interventions depending on how much they restricted the calories, right? They often do outperform them though because they’re more effective at lowering insulin levels. You also have a higher metabolic rate when you eat fewer carbohydrates. So, I actually talk about this in chapter 2. There’s been some really interesting data showing that people who follow a low carbohydrate diet have an increased metabolic rate. So how many calories your body burns per day — and this can be, depends on the studies, some of them are quite a bit — but on average about 135 additional calories per day are burned just by eating a lower carbohydrate diet. Now, some of these trials, what really makes it frustrating is that they will energy restrict the low-fat, high carb diet, meaning make it a low calorie diet. But they don’t usually control the calories on low carb. So, it’s not even like an apples to apples comparison. Like low carb is ad lib, however much food you want to eat. And the low calorie because that diet is so unsatiating and your hunger levels are usually out of control for the blood sugar swings you’re experiencing. You’re so hungry. Like they have to keep the calories restricted because if they let you eat whatever you want on a low-fat, high carb diet, you’re going to default to overeating and then you’re not metabolically as efficient as you are in low carb. So even in the low carb diets when they’re not restricting the calories, often times people do end up eating a little bit less because they are more satisfied and you’re not fighting this like blood sugar roller coaster day in and day out. I would also say one of the tricky things about just any weight loss diet is you have to be careful about what kind of weight loss you’re experiencing. Now, certainly on low carb, you lose some water weight because as your insulin levels go down, you pee out more water. You don’t hold on to as much. You’re not as like puffy, so to speak. But if you’re eating sufficient amounts of protein, additional weight loss is going to come from fat loss versus burning your muscle for fuel. If you’re on a low calorie diet and it’s not high enough in protein, which is the dietary recommendations and our guidelines, you end up losing muscle mass if you’re not shifting your macronutrients to increase protein. And that ultimately is not going to help you out with your metabolic function, your ovulatory function, your reproductive hormone levels. We really do want to be shifting to like a healthier body composition, not just like wasting away and losing our muscle.

Lisa Hendrickson-Jack:

Yeah, that’s such a good point. And as you were talking, I mean, what’s interesting is that I’m of quite the strong opinion that when a woman is trying to optimize her cycles for conception, so when she’s actively planning to try for a baby or she’s currently trying for a baby, I haven’t seen, and it is my opinion, but it’s not just because I think it’s interesting. When I’m working with women and looking at their menstrual cycles, women who restrict calories, who are undereating overall, they are not able to maintain optimal hormone balance. And we’re not able to keep the menstrual cycle balanced when we’re undereating calories, especially when you add exercise into the mix. It’s just not a thing that happens. So our recommendations then are a bit different to what many women with PCOS have heard because many women with PCOS it’s like the whole focus especially if these women are in a larger body the whole focus is to get them to lose weight and it’s like they’re not provided with a strategy of how to do that in a way that would also be beneficial for their hormones and their fertility. Right. So maybe share with us why we were so intentional and in terms of our recommendations I guess why at least from my perspective these two competing goals don’t work like weight loss specifically is the goal through caloric restriction and optimizing your cycle and overall nutritional stores and everything for fertility.

Lily Nichols:

Yeah, kind of overlaps into our considerations about hypothalamic amenorrhea, right? Like if you restrict calories too much, you will disrupt the menstrual cycle and you’ll disrupt hormone production. So with energy intake, pretty sure we have multiple studies, but one off the top of my head, if you start restricting calories and you get around or about 25% of calories as an energy deficit — so say your body, I’m just going to throw out a random number, not saying this is representative of all of women, but let’s say you need 2,000 calories per day for weight maintenance, and you’re now eating 1,500 calories per day. You’ve reduced your calories by 25%. That reduction in and of itself, eating 25% less food than your body requires for weight maintenance is associated with significant reductions in estrogen and progesterone levels. Depends on the study that you’re looking at, but they can go down quite substantially. And also, if you’re eating low fat, you can throw that off as well, even in the presence of sufficient calories because you need fat to build your steroid sex hormones. So, you don’t eat fat, we got problems. So, you start putting people on this low-fat, low calorie diet, it’s like a double whammy to the cycle. Now, in somebody who’s in a bigger body and has a higher percent body fat, conceivably you have fat stores that you can tap into for a period of time to maybe maintain some hormone production, but not everybody with PCOS is overweight. And that’s another like myth that we go into in the book. And it’s also just not necessary to deprive yourself and be miserable as a means to achieve weight loss. It’s also usually not sustainable. So, like you might lose weight for a little while. I mean, we know plenty of people who go on yo-yo diets, right? You lose weight for a little while and then it becomes so unbearable to be starving all the time that you eat again and then you gain weight again. Like, we didn’t actually solve the issue. We just starved you for a while and you got tired of it. Now, we’re eating again. And when you look at animal studies as well, I mean, they find really similar things. You restrict the food too much, especially fat and protein, and you start seeing declines in hormone levels and disruptions to the menstrual cycle. So, in somebody who’s already experiencing a disrupted menstrual cycle, why would we make it worse or maybe throw in like a disruption from another angle, like another mechanism to disrupt your cycle? Like, that’s not fair.

Lisa Hendrickson-Jack:

Well, and I think this is something that really stands out to me because of my work when you’re looking at the menstrual cycle because instead of looking at the woman and being really obsessed and hyperfocused on her size because I think this is something that happens to a lot of women too when they present with PCOS where they’re looking for help with something but the doctor can’t see past whatever their weight is and so then they’re sitting there trying to get help for something and the doctor is just focused on the weight like you need to lose weight, but like the woman has issues. So, one of the great things about looking at the menstrual cycle as a vital sign and actually paying attention to the cycle itself is that it helps you. It’s not to say that weight is not an issue at all because obviously we know that it plays a role in overall health and fertility and insulin like we know this. But when we’re looking at the menstrual cycle, then we can have that more objective marker. If we focus on supporting this woman to achieve optimal hormone balance and we can get the menstrual cycle back in line through reducing insulin resistance and balancing blood sugar etc that we’ve been talking about. Some of the other issues may fall into line and so over time the weight may improve. If you improve the insulin resistance over time it’s very feasible just like in the study that you mentioned that the weight will improve. But I think this is something that’s a bit maybe unique about looking at it from that standpoint of the menstrual cycle where we’re not just then making it all because I mean this is just yet another thing that’s frustrating to me that women aren’t being cared for. So if you want to comment on that but I also wanted to ask you about the nutrient stores as well because I do see it to be problematic when you are restricting overall calories. I mean, our goal when you were talking also when we’re thinking about how we’re supporting women to achieve optimal fertility is to give them a way that’s practical to eat and consume food. Like just a way to live so that not only does it improve their cycles and all the things, but it also gives them a framework from which to go. Like you can’t just restrict calories forever. What happens when you get pregnant? Are we still restricting? Like what are we doing here? And how does that impact your micronutrient consumption as well?

Lily Nichols:

Well, I think you’re exactly right in that the conventional approach is focusing so much on the weight versus seeing the weight as a symptom of something being metabolically out of balance in the body. So, we don’t really focus on weight very much in the book at all. It’s just naturally that as you improve your metabolic health and you improve like when you eat more protein, your metabolic rate goes up. When you choose better quality carbohydrates, your total carbohydrate intake usually goes down a little bit, which again is improving your metabolic rate, how many calories your body’s burning per day. We’re improving your micronutrient intake because we’re focusing on diet quality, not just macro ratios or calories or whatever. So you need all these different micronutrients for your mitochondria to like work properly, which is also important for your egg quality too, like once you get pregnant. So we’re kind of taking a more holistic approach, I think, as a whole. I don’t want people to be depleted by the time they conceive. It’s very like shortsighted to look at a case of PCOS and be like, you need to lose weight, eat fewer calories. Like, no education around diet quality. Like you’re just looking at it from this one angle, this one possible intervention instead of you can actually achieve a lot of the same things from a different angle that’s more supportive of like female physiology as a whole and better prepares your body for conception, which is often the goal, at least for people who are picking up our book. Usually the goal is they want to conceive and have a baby. So the last thing we want you to do is come into pregnancy feeling depleted. That is just not a good scenario to aim for many, many, many different reasons. We want your nutrient stores at their peak before conception. So yeah, we don’t have to like — is that a method that sometimes works? Yes. Do you have to do that? No. Is it less miserable to do it another way? Most certainly. Please don’t deprive yourself, especially long term, because it’ll come back to bite you.

Lisa Hendrickson-Jack:

Well, and our conversation today, I mean, obviously, we’re primarily focused on PCOS, and I thought of mentioning also that it’s one chapter, so the book really is encompassing a whole just myriad of issues. One of the things that you argue though is that blood sugar regulation is not only important for individuals who have an overt issue with metabolism, like in the case of PCOS. So maybe share why this whole concept of blood sugar balance and macro ratio is important for everybody regardless of whether they have PCOS or not.

Lily Nichols:

Yeah. Well, I mean I’ve been in like the conversation around blood sugar space for most of my career since I’m also a diabetes educator. So I personally just see this rippling out to just about every possible health issue. When your blood sugar levels are out of whack, it naturally leads to a state of inflammation in your body which disrupts — I mean you name it — just about everything like the health of your cardiovascular system, hormone balance, muscle repair, liver function like it is an emergency when your body is experiencing at least on a regular basis really high blood sugar. Even your like nervous system and like adrenal function gets a little out of whack, a little uncomfortable when you’re always on this blood sugar roller coaster. For the fertility component, we do know that there are delays in conception observed in women who have blood sugar levels even on the higher end of the so-called normal range. So in other words, even blood sugar elevations that are below a diagnostic threshold for pre-diabetes or diabetes can actually be problematic. So we don’t know for sure why all these things are happening. I mean I know from my work in pregnancy that high blood sugar levels can actually be teratogenic. So they can cause birth defects particularly early in pregnancy when the organs are forming. That’s all in the first eight weeks of pregnancy. And again, like half of that period of time, you don’t even know you’re pregnant yet. But we don’t know what exact time points like the elevated blood sugar is causing issues. Is it at the time of fertilization? Is at the time of implantation? We know that there is a disruption there. And we know as a whole when it comes to the menstrual cycle, elevated blood sugar levels can affect your hypothalamic-pituitary-ovarian axis. So like how your brain and reproductive organs and everything are communicating with one another. So I mean add in the man too. It affects sperm quality. But look at the egg quality studies and like outcomes from assisted reproductive technology interventions and you see poorer outcomes as you see blood sugar levels rise to higher levels. So, I’m a proponent of everybody for their own well-being, physical, mental, and otherwise aiming for blood sugar balance. At least having some awareness, it just makes you feel better on like a day-to-day basis. But from the standpoint of fertility can greatly improve your chances of conception. And then as you get into pregnancy, we can reduce your risk of developing gestational diabetes or having a difficult to control case for example or even reducing your risk of preeclampsia like blood sugar and blood pressure go hand in hand. It’s like it’s related to everything really.

Lisa Hendrickson-Jack:

Well, I thought of another question. This is something that we have spoken about quite a bit. It’s — I don’t know how controversial. I think it depends on which crowd you’re talking to, to be honest. In terms of carbohydrate recommendations because I think depending on where you look, there’s some practitioners that would suggest that there’s a minimum amount required and that we shouldn’t go too low. And you mentioned a little bit of this with respect to PCOS already, but maybe share a little bit about what you found when you were researching for this book and where we essentially came to in terms of our recommendations. Hopefully this question was clear for the listeners, but just to kind of wrap it up, we tend to recommend like more of a lower carb, but not like a ridiculously low carb, but like a lower carb type of approach as a way of balancing blood sugar to support overall hormonal health. And also part of the recommendation though is that you’re getting sufficient protein and fat which naturally crowds out the excess carbohydrates so that you’re getting enough food overall to clarify that. But like this is different to some of the recommendations overall because many practitioners kind of recommend more of like a you shouldn’t eat less than this many carbohydrates type of thing. So I’ll leave it over to you.

Lily Nichols:

Yeah. So, I mean, I’m not new to the controversy surrounding carbohydrate recommendations, and I feel like it was actually hard to like condense and keep the carbohydrate section like under control because there was so many qualifying statements necessary to clarify exactly what we mean. And like my first book was controversial because I was going into the carbohydrate recommendations for pregnancy because there’s this minimum number given out and if you go below this number you will have problems with your baby and like that’s not true. So I had to take a whole chapter to like unpack that and this one felt very similar. So in the women’s health space, some people have talked about there being a minimum threshold of carbohydrates required to induce a luteinizing hormone spike which triggers ovulation. And so if you go below this theoretical minimum level, they say you won’t produce enough luteinizing hormone to trigger ovulation and your ovulation is messed up. So the number that is commonly given is 130 grams per day. I was like okay. So I looked into this like but I spent months actually looking into this question because I wanted to see if there was more than the study that people cite about this and in fact there is not. So the only evidence really that’s given to back this claim is a study that tested not a low carbohydrate diet but a low calorie diet on menstrual cycle disturbances. It was a well-done trial like controlled feeding trial. Love controlled feeding trials. They’re not real world at all but you can test the mechanisms and the specifics of things. So they look and the controlled feeding trial for anyone who doesn’t know is like when they tell you exactly how like you’re eating a specific amount. Usually most of them all the food is provided or you’re actually in an inpatient setting where you’re like admitted to a hospital and like the metabolic kitchen, the research kitchen prepares all of your foods. Everything is like precisely calorically measured. They might measure your like metabolic rate and like how many calories you’re burning and then like match your diet exactly to that amount of calories or percent deficit. It’s very controlled. So in that study they found that when you restricted the calories too much the menstrual cycle was disturbed as you typically see — especially you see a short luteal phase start first and then when calories get restricted beyond a certain level ovulation stops. But this study was not low in carbohydrates. It was low in calories. Carbohydrates made up 57% of energy intake. That is not a low carbohydrate diet. Carbohydrate recommendations in our dietary guidelines are 45 to 60% of calories. This was 57% of calories. They were not testing a low carb diet. They were testing a low calorie diet. That said, that study did have some really confusing sentences in their — it was either just the discussion or the results section where I can see how somebody just scanning for the literature for proof that low carb is harmful would like pull out a sentence and say, oh, it’s 130 grams of carbs as minimum. But no, this wasn’t a low carbohydrate diet. It was a low calorie diet. I was actually not able to find any evidence in the literature to support the idea that a low carb diet specifically in the context of a diet that is providing enough calories — so a non-energy-restricted diet — is harmful to hormone balance or fertility. And I think the PCOS studies are a perfect example where we often see improvements in ovulatory function when carbohydrates are restricted. But those again are in the context of a diet that has enough energy. So can a low carbohydrate diet screw up your cycle and screw up ovulation? Yes, it could. If your interpretation of a low carb diet is low calorie or — I think we originally had it like — low food, low carb does not mean low food. I think we had to edit it because our editor was like I don’t like the way that this sounds. That is a common misconception. And I would also say if you are the type of person where when you eat low carb, you’re finding yourself so much more satiated without even trying eating fewer calories. You might accidentally undereat. And in that case, you might need to be diligent about actually like eating enough food. If it gets to the point where now your cycle is getting screwed up, you might want to potentially up your carbs or up your calories because you might be accidentally undereating. It’s just so satiating, particularly when you get the protein up. It’s so filling that often times calorie intake can spontaneously decrease. But there is not a study showing low carb messes up your luteinizing hormone spike. It was a low calorie study and it’s unfortunate that that has been perpetuated everywhere as fact. It’s just not the case. I think people misinterpreted the study.

Lisa Hendrickson-Jack:

And I think one of the challenges is that to clarify like we’re not suggesting you eat in a really restricted way like you know what I mean? Like we’re not suggesting like to have this like math equation on the wall with like you know you can only eat this many like it’s not like that. It’s more I think the problem is that when you are confusing this information and making it seem like we need to have a certain amount of like focusing on the carbs part, I think what can happen is that the part about getting enough protein and fat is lost the discussion. Right? What I’ve found is that most of my clients I don’t have to tell them to eat more carbs. It can happen because there are some people that might take it to the other level where they’re really restricting carbs and working out a lot. But what’s happening is not a carb problem. What’s happening is a low food problem for these individuals. And because they’re severely restricting carbs and you can see that that’s happening, then we’re blaming the carbs. But really in those types of situations, it’s a low food problem. So I think again when we bring it back to the menstrual cycle and we actually see what’s happening real time with women in terms of their luteal phase length, there are signs of potentially low progesterone because the second half of the cycle, the luteal phase from ovulation to your period. The whole cycle is sensitive but I feel like that is often where it’s easier to see the issues first. So when we’re paying attention to the menstrual cycle we can really hone in on what the actual problem is. And if it really was carbs and not food, we would see that. But that’s not what we see. So, I’m really glad that you clarified that, Lily, because that was certainly a topic that we talked about last time again. There’s so much we had to like justify — we go into the numbers a lot, not because we want people to count the numbers a lot, but I need to like qualify the recommendations at a certain level. So when you just gave the example of somebody who’s very active, I actually don’t think a low carb diet is necessarily a good fit for them. Can it work? Yes. I know athletes who follow a ketogenic diet. Is it necessary? Usually not unless they like really really want to do that, but then they have to be super diligent about getting enough calories in, right? So you have to like look at the clinical scenario and like decide. But this whole concept that if like 130 grams is like this magical minimum number doesn’t even make sense in the context of global diets because you go to latitude extremes like the Arctic. Even if you tried, you can’t eat 130 grams of carbohydrates per day for a very large portion of the year because nothing is growing. The ground is frozen over and you’re eating animals. And I can say this because I’ve lived in Alaska. Even in the summer, the sweetest thing that you can get is like not very sweet berries. As a whole, their diets are they default to ketogenic diets. If none of these women over the course of history had enough luteinizing hormone to ovulate, then those populations would have died out because they couldn’t reproduce. And that is not what happened. Clearly, like our bodies can adapt to all sorts of different levels of macronutrient ratios. Some of those are sort of genetically programmed arguably and other ones are just dependent on our diet and lifestyle choices. But yeah, this whole concept that there’s this like fake minimum level — it’s like this is fake news. This is not a real thing.

Lily Nichols:

Yeah. Got to keep it real. And that’s like I always — I’m just like the annoying like about the menstrual cycle. Like let’s look at the cycle because at the end of the day it cuts through all the nonsense.

Lisa Hendrickson-Jack:

So, as we bring this to a close — I mean, we could just keep talking, but we have to wrap up soon here. So, I’m going to throw this to you and I’ll let you — because it could take longer, but we’ll see. For the listener, I mean, like I said, today we focused a lot on PCOS. I’m really excited to share this episode with my audience and everything, but if you would take a moment to kind of summarize some of the general recommendations. The book is Real Food for Fertility. So for the listener who’s like well what are the foods and also maybe just share a little bit just kind of summarize what some of our recommendations were globally like overall what listeners can expect when they grab a copy of the book.

Lily Nichols:

So general outside of the context of PCOS. So, I mean, if you’re listening and you already kind of know my work, I mean, obviously from the title, real food — essentially, we’re talking about a whole food diet that includes some specific nutrient-rich foods to make sure you have enough micronutrients, vitamins, and minerals to optimize your hormone levels, reproductive function, prepare your body for pregnancy, and your partner as well. So, as for foods, we’re talking about animal and plant foods. So, for the animal foods, meat, poultry, fish, seafood, dairy products. For plant foods, really the whole gamut — vegetables, fruit, nuts, seeds, legumes, whole grains in moderation, at least with the whole grains, but you know, an array of foods. We do have a chapter that specifically focuses on some nutrient-dense foods that you may want to emphasize even more of because of their nutrient density. So, organ meats are one, eggs with the yolks, certain types of seafood can be really beneficial. Certain types of dairy products can be beneficial. Fermented foods, they have a lot of probiotics, improve your microbiome. Certain types of produce are particularly nutrient-rich and full of antioxidants. So we have sections that like emphasize those and then throughout the book we’re kind of weaving in the nutrition component into everything. So the first part of the book is very heavily nutrient focused. It’s like this is the dietary like structure we’re talking about. And then we get into more the specifics on how those things play into potential like menstrual cycle issues, egg quality, sperm quality, PCOS, hypothalamic amenorrhea, a variety of like reproductive challenges and fertility challenges. And then we do tie it together as I do in my other books with sample meal plans and recipes. And yes, they’re all different recipes than from either of my other books. I intentionally did not want to overlap on those. So, I did have to throw in liver pate in there, but we have variations to the liver pate. So, it’s not exactly the same as the ones in the other book. So, still kind of like brand new and fresh even if you’re already kind of familiar with this way of eating. I think some of the major takeaways we had from our advanced review team and I even got this from some dietitians like, wow, I thought I was well-versed in this, but I learned quite a bit about the macronutrients. Like I had no idea how that affects the menstrual cycle and I didn’t know this research on carnitine or taurine or how that affects ovulation. And so that was reassuring. There is a lot of information in this book that just has not been written about before, I think we can conclusively say, and hasn’t been put together because a lot of your audience knows something about the menstrual cycle, but like we don’t really know Lisa level menstrual cycle information.

Lisa Hendrickson-Jack:

Yeah, for sure. Yeah. So, we’re really thrilled about the book and how it turned out. We’re super thrilled about its release this week. We invite you to head over to realfoodforfertility.com and all the links will be there for you to grab your copy. You can also search for it on Amazon. And Lily, thank you so much for coming to the show again as the guest I’ve had the most times. You’re my most repeated guest. Now I’m really getting up there, right? This is what, appearance eight or something? So yes, we’re somewhere in there. And I’ll link all your previous episodes for the listeners who want to hear more from you. So yeah, thanks so much for being on the show and I’ll talk to you soon.

Lily Nichols:

Talk to you soon.

Lisa Hendrickson-Jack:

Thank you for listening. If you enjoyed today’s show, please share it with a friend. You’ll find the show notes page over at fertilityfriday.com/607. I hope that you enjoyed today’s episode with Lily. It is always a treat to have her on the show. And since the initial release of Real Food for Fertility on Valentine’s Day of 2024, it has just been incredible to see how this book has changed the conversation about fertility, how it has really introduced the importance of fertility awareness cycle charting and blended it with the importance of evidence-based nutrition to optimize fertility, to support sperm and egg quality, and to really support women who are wanting to conceive. This is an area that is underserved, and I’m sure all of you listening know that. Fertility challenges, infertility are so common, and they’re becoming more common. The stats say 15%, which is one out of every six couples. So now more than ever, this book is so important. If you haven’t had a chance to grab your copy, you can download the first chapter for free at realfoodforfertility.com. And with that said, I wish you a wonderful and prosperous 2026. Let’s make this year amazing. And so, as always, until next time, be well and happy charting.