How to Optimize the Circadian Rhythm of Your Fat Cells with Dr. Fiona McCulloch

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If we're kind of not synced up with what our fat cells are doing, you know, according to the time that we're eating, then we're not going to be, you know, getting all the benefits that we're trying to get from the changes that we're making with the diet.

Here's JJ Virgin Triple board certified nutrition.

And fitness expert and four time New York Times best selling author.

It's time to reignite wellness.

Hey, it's J.J. here. So this is super cool. We have had my buddy Dr. Fiona McCullough on before and I love reading her blog and we will put the resources, her blog and all that stuff in the show notes@jjvirgin.com forward/doctor Fiona Clock D R V F I O N A clock C L O C K. You'll find out why in a minute. Anyway, I was reading this blog she wrote about fat cells and their circadian rhythm and I'm like, oh my gosh, I need you on the show talking about this. So that's what we're going to be talking about today, that fat cells, your fat cells actually have a circadian rhythm. And when you know what that is, it will help you make the right decisions about when to eat. Because I'm kind of obsessed with not just what to eat, but also when to eat because it makes a big difference. Let me tell you a little bit about Dr. Fiona. She's a naturopathic doctor. She's the founder of White Lotus Integrative Medicine Clinic in Toronto, Canada. She's been serving thousands of women with hormonal issues since 2001 and is an expert in in PCOS. She wrote the book 8 Steps to Reverse your PCOS. She's also the medical advisor and has developed the nutrition methodology for the open source Health PCOS project. And she has an amazing gift for all of you today as well. Again, you'll be able to get all this@jburon.com Dr. Fiona Clock and now you know why I put clock in there. She's going to give you a great resource on insulin demand, so you're going to be able to grab that too. Now, before we dive into the show, I want to do a shout out to Vicki Platt, who left us a five star review on Apple Podcasts, says I've listened to several podcasts while getting a fall garden bed ready for plants. Listened about skin and sex, the brain, sleep and more. Learned so much. Thank you JJ Virgin for having such informative guests on so many topics. All right, you are so welcome. What you're going to find is that we are in the process of. Well, probably if you're listening to this, you are in season two. Now, it took us a couple years to go from season one to season two, but we have spent a lot of time upgrading based on information that you guys have been sharing. So now we do a solo every week where I go deep diving into a topic that you've expressed interest in. I do a cool interview with a guest every week and then we've got Friday Q and A Friday. So make sure that you are subscribing at subscribe to JJ so that you can get all this awesome stuff. Of course, while you're there, I'd love to have a review from you so I can shout you out. And I also if you've got something you'd love to know more about, let us know so we can go out and either seek the best expert in it or I will do my solo on it and same with questions and answers. All right. Now before we dive in today, I want to share another fave with you. Here it is.

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Hey, super excited to have you on the show. Dr. Fiona McCullough. Thank you so much.

Thank you so much for having me, jj.

Well, it's been a while. I had to. I read this article and then I bombarded you because it was so fascinating. So, I mean, I am really thrilled to be diving into this whole idea of about circadian rhythm and that fat cells have a circadian rhythm. Oh my gosh. Like, so awesome. So let's kind of take it back from the beginning and talk about what the heck is circadian rhythm anyway? And why does it matter?

Absolutely. Yeah. When I found this study, I was just like, mind blown. I was just amazed with it. So, you know, the circadian rhythm is really a rhythm of time, you know, with the body. And, you know, typically it's thought of as a 24 hour period. And so it's the way that things happen at certain times in the body. So, for example, we all know that cortisol, the stress hormone, has a circadian rhythm where it's released primarily in the morning and then the levels decline throughout the rest of the day. And many other things in our bodies run on a circadian rhythm too.

So, like, first of all, this, this, like, I never thought, I've always thought about circadian rhythm and how it impacted health and weight in terms of, like, I remember the first time I looked at it, it was. I had a client early on, this was probably 30 years ago, so 25 years ago, and she was a nurse who did the graveyard shift. And she said to me, she goes, you know, my friends have told me that I can't lose weight because I do the graveyard shift. Well, I didn't know anything about this. Fiona so said, oh, that's ridiculous. Of course you can. That wouldn't impact it now. She lost £100. And I kind of at the time thought, well, maybe it was better. I didn't know what I didn't know, but I now know that that could have a huge impact on it. So let's talk about, like, you know, how does circadian rhythm affect weight loss and why? What's going on?

Yeah, absolutely. So there's been a lot of research into this in the past maybe 10 years. And what we've been finding, you know, time and time again in different studies is that really, if your sleep is disrupted or if you happen to work, shift, work, like this nurse who is your client, there is definitely weight gain associated with that. There's more insulin resistance, which causes us to gain weight. And it's been, you know, sort of known that when people start shifting their hours, when they start traveling to different time zones, they. They actually can easily gain weight. And in particular around the midsection, because it does influence our levels of insulin in the body, which causes to gain weight around that area.

So you talked about that and gaining weight, but we're really talking about gaining fat. Yes. So let's kind of dig into fat and what it really is, because it's not. I remember, like, years ago, it was like, fat's just like this bad backpack you're carrying around. It's like. Well, no, not really.

Yeah. Yeah. You sort of remember that wheelbarrow from Oprah where she brought that out? Just like a big, you know, mound of fat.

Yeah, it's just a blob of stuff.

Yeah. And, you know, like, what they've been finding is that's not true at all. So fat is actually an endocrine organ. So it actually makes hormones. It does lots of things. It tells our brain how much energy we have stored. So it's a very active, you know, hormonal system, our fat. It's not just, you know, a storage unit that's just, you know, pumped with energy, and we just burn it. It actually does a lot of communicating with our body, and it's actually really important for our metabolic health, you know, how our fat cells are actually functioning.

So then how does this relate to, like, fat cells? Circadian rhythm? How does this all play together?

Yeah. So this study was really interesting. And what they did was they actually took some people who fairly normal circadian rhythm to start with, and then they actually started to put them into a routine where they were eating at the same Time, they were sleeping at the same time. And they did that for 10 days to kind of get them all matched up and on the same kind of clock. Then what they did was they took away that routine. They took away daylight temperature and they put food into a very small standardized window which was evenly distributed throughout the day. And then they just looked at the actual time and they looked at what the, the people's fat cells were doing. They started measuring the fat cells every six hours. So they actually biopsied the fat cells and measured what their genes were doing inside. And what they found was that the fat cells just based on time, so not based on, you know, how, how long ago you've eaten, not based on when you've been sleeping, but just simply based on the time your fat cells do. So there was a huge difference between what the fat cells were doing, for example, in the morning and at nighttime.

So what were they doing? What were they doing in the morning versus nighttime?

It's so interesting because in the morning the fat cells actually did a lot of different things that were sort of similar to manufacturing. So they were involved in, you know, making hormones, making cytokines that send signals to the rest of the body, making, you know, a variety of different adipokines, which are, you know, different little hormones that our fat cells signal to tell our body to do different things. And then at nighttime, what they found was that the fat cells were in a completely different state. So what they were doing was performing antioxidant actions and breaking things down. So they were breaking down, you know, fat itself. So that's called lipolysis. So they do that more at nighttime. And they were breaking down organic acids, which are byprod of different metabolic processes in the body. So they were in completely different states in the day and in the nighttime.

Well, so knowing that then, because something I've been so fascinated with is, and I've watched this whole Progression, Fiona, from 20, 25 years ago where you were supposed to have breakfast, a snack, lunch, a snack, dinner, and then, oh my gosh, you better have a snack after dinner too. It was like really from, from that to going, all right, well let's not snack, to going, let's eat within a 12 hour period, to let's eat within an 8 hour period to the latest I just saw was a four to six hour period. And from that first shift of intermittent fasting, saying, hey, skip breakfast and have a later, you know, have lunch and dinner. And I kept thinking, well, everything I've ever looked at says do this earlier so I'm really fascinated by, you know, of course we want to at food quality and we need to look at what we're eating. But I think, you know, what this is really showing is when you eat matters. And I wonder if some of this is, you know, how does this tie into all of this intermittent fasting, time restricted eating stuff and what are the lessons that we can take? I know I'm throwing all this stuff at you. What are the lessons that we can take from the fact that these fat cells do different things at different times with how we should be tying that to when we should be eating?

Yeah, of course. And you know, what we want do with this information is just use it to maximize our metabolism. Because if we're kind of not synced up with what our, our fat cells are doing, you know, according to the time that we're eating, which also affects them quite a bit, then we're not going to be, you know, getting all the benefits that we're trying to get from the changes that we're making with the diet. So if you look at eating at night, you know, your fat cells really aren't supposed to be storing and manufacturing at night. They're really more in a burning and also in a breaking down mode. So you're sort of losing that benefit that you're getting that normally happens at night. And that's really important for metabolism. You're interfering with that. And then in the daytime, you know, in the daytime really we are supposed to be manufacturing and the fat cells are really involved in a lot of different processes. So fasting in the morning can be okay. And certainly these fasting windows are much better than eating continuously all the time. But shifting it more towards eating earlier in the day and stopping earlier in the evening is always going to work better with that clock in the fat cells because that clock depends more on time and not so much on eating or sleeping.

Yeah, that's, you know, it's like, that's what I'm noticing that seems to make the most sense. I think some takeaways here and I'd love to just get your opinions on them. Number one, a takeaway of stopping eating earlier in the evening from what you've seen, you know, how many hours before bed. Because I just read the latest one that was saying, hey, you know, ideally you'd be eating from 8am till 2pm and I'm like, wow. But I also think, well, wouldn't it matter what time you really are going to bed and what time you are waking up? Because it's very different for someone waking up at 6 versus someone waking up at 7. Very different for someone going to bed at 9 versus someone going to bed at 11. You know, how many hours before bed would you think it's ideal to shut that kitchen down? Because I, I think that of anything we do is probably one of the most effective things that you could start with is just to shut the kitchen down.

Oh, yeah, absolutely. So I always tell people, you know, 7pm or three hours before bedtime is kind of, you know, what to shoot for. If you can do a little bit longer than that, that's even better. So if you could stop eating by six, that's even better. And the research shows us as well that the stuff that we eat at night is always going to be worse than the stuff that we eat in the morning. It's just sort of, you know, the end of the day we're all stressed and, you know, chocolate is like what we want at night. Right. So it's not only just the time and getting into that rest state, but also the types of, of choices that we make at night that are not the best.

Yes, we do tend to be much more virtuous in the morning. It's way easier. And it sounds like if you were going to. So here's the other side of the coin. If you were going to blow it, if you were going to go and say, you know, and I'm not going to even call it cheat because to me, I look at it and I go, we should get like a B plus on our diet. You do not need to be perfect. But it is funny because when you look at, like when people do tend to go sideways, you know, they're not having birthday cake for breakfast most likely. Right. So if you were going to go sideways a bit, when would the best time to be?

Well, you know, like what I always tell people is, you know, if you're going to eat a little bit more, you know, definitely having a good breakfast is very important. We're also not as hungry in the morning. So, you know, if there's something that you're eating in the morning, you're really not going to overeat on it. I think what the way I look at that is, if it's something that you really enjoy and you're really moderating the amount, it could be okay to have that with your dinner, but then to cut it off after that. As long as everything, you know, your whole meal is really balanced and stable with respect to how it'll affect your blood sugar so making sure it has lots of protein, lots of vegetables, which gives you fiber, lots of healthy fats, those will definitely just stabilize your blood sugar. And then if you were to have a couple of squares of dark chocolate once in a while with the dinner is actually a good time to do that because you are going to be embarking on a fast after that where you're not going to be eating for a little while. So it is actually I always view that as okay to do. But you know, of course if you're going to have a treat and you have it with your breakfast, you're much less likely to overeat on it just because of your natural appetite being low at that time.

So last takeaway from like all this information, what are your recommendations now in terms of like, are you having people do eat within an 8 hour window, a 12 hour window? Like what, what's your recommendation out there as a big insulin, the, the queen of really understanding how insulin demands are on the body and how best to regulate these things. What would you tell?

So I work primarily with women who have hormonal issues and so we always have to be like a little bit more gentle because sometimes, you know, the hormonal situ, these situations can become worse, you know, from certain types of more strenuous fasting. But what I find for everyone is that a 12 hour window is, you know, generally works for most people very, very well. And then, you know, for people who've got a lot of weight loss resistance or insulin resistance, I'll often do, you know, an eight hour window for those, those patients with two meals. And I have also recommended, you know, a single meal a day for certain patients who are, you know, maybe really, really insulin resistant and struggling with type 2 diabetes. And that should always be medically supervised. But I've used a lot of different windows and I think it really depends on your level of activity, your level of tolerance for fasting, how healthy you are in the first place and how bad the insulin resistance is that you're trying to overcome. So for somebody who's got, you know, who's a pre diabetic, who's got a lot of insulin resistance, they actually sometimes need to move into more of these shorter windows of eating and it just gives them so much more time without insulin playing a role. So when you're not eating, your insulin will go down at that time and that just helps people to become much more sensitive to insulin because there's less of it there all the time. So I have actually, you know, tried a lot of These different windows. And I think the most important thing, though, is to just make sure there is a nice block of at least 12 hours where there is no eating happening to allow all of these different functions in the body to work at the right time. It's almost like an interconnected system. And if you're eating during that time, you're almost messing with many different mechanisms of the body that are meant to sort of be in a fasting window as opposed to an eating window.

I love how you explain that, and I just love that we are looking beyond just what you're eating as to when, as to a real powerful way to help with blood sugar and insulin. And I know you've got one other thing you're going to be giving everybody, and that's your food insulin demand list. And let's put this whole thing@jjvirgin.com Dr. Fionaclock, because I think we've done a Dr. Fiona, because you are a reoccurring guest of brilliance on the show. So we'll do Dr. Fiona clock, tell everyone about the food insulin demand list so that. That they will be able to get as their gift card.

Thank you. J.J. and I. You're very. You're one of the pioneers in, you know, understanding insulin resistance. And I remember following you, like, many years ago and watching what you were saying about this. So the food insulin demand is actually a metric kind of similar to the glycemic index, but it tells us how much our insulin goes up when we eat a food. For example, one food that's very spiking to our insulin is dairy protein. Even though it's low in the glycemic index, it causes our bodies to make a lot of insulin. And so many people react badly to dairy, either from sensitivities, but also because of the massive spike of insulin it causes. So this list goes through all of the most common foods that we would eat and gives you their food insulin demand number so that you can learn which of the foods might be really triggering your insulin to go higher than you're imagining.

Yeah. So key critical. It's, you know, I think back to just the classic agave, right. And crystalline fructose that they'll put on a label and they'll go, you know, low on the glycemic index. And it's just why we have to look beyond that because you can still spike insulin and have something low on the glycemic index. So I think this is just brilliant. I'm excited everybody will grab this. I super appreciate it. And I appreciate your time today. Dr. Fiona, thank you so much for coming back on the show.

Thank you, jj. It's been amazing to be here again.

So after the break, I'm gonna give you your top takeaway from this episode. So stay with me.

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Happy Price Priceline. Welcome back. All right, this is the time when I do a debrief, give you an action item after what we've heard today. And so again, I am setting this whole protocol out on a roadmap for how to just continue to uplevel your health. And it starts with improving the quality of your food, then doing a, doing some detoxifying, then starting to figure out your food intolerances. But along the way too, while we look a lot at focusing on what you're eating, I also want you to think about when you're eating. So if right now you haven't really been paying attention to that, step one is to get that kitchen closed at least three hours before bed. Now, this does not mean go to bed later. Okie dokie, deal. And to give yourself a solid 12 hour overnight fast. So if you stop eating at 7, then you do not eat breakfast before 7 in the morning. Kind of my rule of thumb now is to eat in the morning when you get hungry. So that might be an hour, two hours, three hours after you wake up and stop eating, at least three hours before bed. Longer is better. And so that starts with doing a 12 hour fast. And then we just continue to look at if we can shrink that down to a, to a 14 hour fast and then maybe to a 16 hour fast. I tend to do those more on the weekends. When we get up later, we can eat earlier. But again, a lot of great research coming out now on shortening that feeding window and doing time restricted eating. All right, just another little reminder. Make sure you get the cool information from my buddy Dr. Fiona at jjvirgin.com Dr. Fionaclock. And if you haven't left a review yet, I would love, love, love to shout you out. So subscribe to jj. That's where you go so you don't miss any of the episodes. And while you're there, leave a review and I will give you a shout out. All right, see you next time. Bye.

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