Isabella (00:01.999)
Alright, so first question I’ll start with is where did you grow up?
Emily (00:08.792)
So I grew up in Sanger, California, which most people probably aren’t familiar from or familiar with. it’s in Fresno County. It’s kind of the one of the more rural areas. So when you see you got raisins or almonds or whatever other produce from California, that’s probably where it came from.
Isabella (00:27.879)
Did you, did that kind of inspire any interest in science or plants for you or was that like not on your brain at all when you were growing up?
Emily (00:38.863)
maybe a little bit. got into science. I really have always loved animals and that’s, mean, I, I lived on like a two and a half acre lot and it was surrounded by agriculture. And so we had a lot of like outdoor cats and dogs and I’ve always had animals around me and you know, the neighbors had chickens and there’s cows down the road. So I was very around, animals in that way. And I originally had decided I was going to be a veterinarian.
And then that ended up not working out for whatever reasons. but it had gotten me into a biology major in college. but actually when I was really young, I loved math and I hated science. remember going to a STEM event and being like, I’m only here for the math. I really don’t like science. And I think what it really was, it wasn’t that I didn’t like science is that I wasn’t into geology at the time. You know, I mean like what our education system defines as science is such
so many different things and you don’t actually get into like applying logic and thought and experiments until you’re much older. And so when it got to the point of like what I, my kind of science now, I guess I really fell in love with it. But when I was a kid, yeah, it was everything but science and what I thought was science.
Isabella (01:55.815)
It’s so funny. I obviously am not a scientist now, but I did biochemistry and that was like what was really interesting to me and my boyfriend’s a geologist and it’s just like opposite ends of like time scale and size, like total opposites. Yeah.
Emily (02:12.77)
Yeah, science is a very vague term and you might love some of it and hate others parts of it. A hundred percent. Yeah.
Isabella (02:18.253)
Yeah. So yeah, how did you, what is chronobiology? How did you get to that as a focus?
Emily (02:26.604)
Yeah. I mean, I didn’t know it existed either when I was at, until I was in college. so it all started by taking a class. So I was actually just realized I was no longer pre-vet. I didn’t know what I was going to be. It was my second year and I was an integrative biology major. So that meant we got to take lots of different types of biology courses. And I was thinking maybe plants or maybe that, and I wasn’t sure. and I ended up taking this class called hormones and behavior, with Lance Kriegsfeld.
And I just loved it. I loved it so much. It was so interesting. was neuroendocrinology and seasonal reproduction. And there’s a lot of circadian components to that, or not just circadian, but biological rhythm components. There’s many different types of biological rhythms. Circadian, which is a daily rhythm, is just one of them. But especially when you think about seasonal reproduction, you have these circannual rhythms and like menstrual rhythms and title rhythms, and you have all these different things. And I was so fascinated with it. And I was talking about it all the time and I just…
of fell in love with it. And then I just kind of bothered him until he let me into his lab. And so then for the next two years, I worked in his lab and I found I just loved my time in the lab. And I was like, well, that’s what I should be doing then. And so that kind of bordering between circadian and neuroendocrine led me to UMass Amherst because they have an amazing neuroendocrine program. And they also had an amazing circadian biologist there. And so that’s where I went. And for the first
Like six months I was doing more neuroendocrine stuff and then that very quickly transitioned into more strictly circadian stuff and just kind of where the passion fell and I’ve been there ever since.
Isabella (04:09.927)
And I know that you’ve said, so for a while you were working with like animal models, which kind of continued the vet track a little bit in a way. And then it kind of became more about humans. Can you tell me about that transition at all?
Emily (04:28.428)
Yeah. So I used to work on hamsters, Syrian hamsters, which is like the pet you might have from a pet store. And you think about having a hamster. and almost no other field uses hamsters. Chronobiologists use hamsters because they have extremely precise circadian rhythms. Like I could tell you when some of these animals were going to start running on that wheel, like with a countdown almost to the second, it was, they’re amazingly precise.
They also are not social in the same way that mice are. they’re singly housed. So it’s much easier to track their behavioral rhythms because if you have a cage of mice, you don’t know who is doing what. And in a hamster, you know, they’re just doing this. They’re also a little bigger. They’re easy to, they can handle them. There’s, there’s a lot of benefits, but they are pretty unique to chronobiology. So I had been working with Syrian hamsters. worked a little bit with Siberian hamsters who also have the seasonal reproduction thing, and they were wonderful for answering certain types of questions.
And I was looking to do my postdoc. was trying to figure out what am I going to do next. And a lot of the advice I’ve gotten, I think, is still advice that you get is, about what’s going to be exciting in five years from now. Figure that thing out. And what do you want to be an expert in in five years? And so for the last couple of years of my grad school, was inviting professors to come give talks at UMass or networking a lot. And one of the people I invited was Sachin.
And I loved his work, but I originally thought there’s no way I could work with him because I think I do want to get out of the rodent space. I want to try something different. And that’s when he told me about the human work that they were doing. And I was like, well, that I’d be very interested in. And it was really this kind of idea of like kind of very tangenty, but circadian system really like the study of it really came out of curiosity.
there was not like an immediate need for it. It was a curiosity and an observation. And then it became, is, these are observed and this is what’s going on in life. And then it became to the, if you mess the system up, it’s really bad. But that’s kind of where we ended. never like, we really, the field is so new to, well, can you improve these rhythms to improve health? And that’s kind of even where some of the animal work was starting to go. And then when I talked to Satine about his work in time restricted feeding, and then translating it into human work,
Emily (06:54.016)
It was just such an exciting opportunity to say, now have a system that we have basic hardcore evidence for. It hasn’t been tested in humans yet. That seems to be like a pretty low hanging fruit that might be a major thing. And so it ended up working out where I got to come and switch from rodents to humans. And I mean, it’s a totally different system. know, working with humans is very different than working with hamsters.
But the biology is the same. It’s all based on the same ideas. It’s really just what your experiments are that changes. But I don’t know. I was amazed that it felt very similar to me. And when I would tell people about it, it’s like they thought I was doing something they could never understand before. And now it was easy to understand. It was like, it’s the same thing. don’t get how it’s so different. But it is. Human circadian rhythms are much easier to relate to. everyone eats. Everyone sleeps.
Isabella (07:40.871)
you
Emily (07:49.6)
understand this at just a more basic level. It just makes sense because we all live it. And so that’s been a really fun part of it too, is getting to be this kind of like relatable thing that people can apply every day.
Isabella (08:04.475)
Yeah. So, okay, circadian rhythms like actually in your body, in your cells, is it all related to metabolism? Or no?
Emily (08:17.782)
Yeah. So circadian is literally just Latin for about a day and your, how everything in your body works has pretty much a circadian rhythm. know that the, that metabolism as a whole, like almost every component of it has some type of circadian regulation. So it’s not to say you can’t digest things or eat things at different times of day, but you’re to be better or worse at it different times of day. The way your glucose is going to respond to food is going to be different at different times of day.
If you break down fat or not will depend on nutrient availability and that’s usually time. and so yes, it’s super tied into metabolism at so many levels that it’s hard, you you can’t just like name them all. It’s almost like on every molecular circuit, can usually find a circadian component and we know that there’s a lot of specific, when you think of metabolism or metabolic health that are directly tied into circadian regulation.
Isabella (09:14.791)
So can you have dysregulated circadian rhythms in different spots in the same body?
Emily (09:21.942)
Yes, yes, you can. So there’s some really cool stuff. like we said, okay, so there’s kind of like three main things we think about as external cues that impact your circadian rhythm. So the first one, I think what was the focus for so long was light and light directly impacts the kind of, central clocks in your brain. And those are going to more directly affect your behavior, like when you’re sleeping, when you’re awake,
Now that indirectly usually affects when you’re eating because when you’re asleep, you’re not actively eating at least while you’re asleep. But when you eat is another really significant cue. And those directly affect the clocks throughout your body more directly than light does. And so if you invert food and time, you can completely switch those clocks into anti-phase of each other.
I mean, just completely. It’s amazing to see how fast they switch and you cannot shift the clocks in your brain with food and you cannot shift the clocks in your body with light. It’s all the, there’s some indirect feedback, but you’re not going to get that kind of a shift. And so yes, when you have these kinds of, when you misalign your behavioral rhythms, you can break parts of your system or at least misalign them where they’re now not working together properly.
and still have others. So you could have a really great sleep-wake pattern, but if you’re eating at super erratic times, the clocks throughout your body are probably not functioning right. Now that will probably have some kind of an indirect negative effect on your sleep as well, but you can definitely break some clocks and not others, or disrupt, I’ll say.
Isabella (10:59.023)
Yeah, I’m not even looking at my questions. I’m just asking questions that I’m curious about. One more and then I’ll go back to my questions. I’m curious about like people or places that have really short days in the winter and really long days in the summer. Is that, does that really mess with you or because it’s like a natural gradual thing and you were like born and raised there, your body is somewhat used to that or like?
Emily (11:03.116)
Hahaha
Emily (11:15.694)
Sí.
Isabella (11:27.589)
Are you performing really differently as a human in the summer versus in the winter?
Emily (11:32.322)
Yeah, no, that’s a great question. And I think, you when you think about these extremes, it gets a little weird, right? And to live in that extreme, you know, those, those day lengths also usually come with fairly extreme temperatures too. These are not the easiest environments to live in. And no, they, have to adjust. So the thing is, is it can be very hard to not have light for long periods of time.
Right. To have weeks without light or extremely small amounts of light. and that can lead to other issues, even if you forget the circadian component of it, that, seasonal affective disorder is a very real thing where, you see this a lot, even on like, you know, the East coast, like New England, where you’re, when you are outside, it’s very dim or it’s too cold and you don’t get enough sunlight. that can be really hard on, effective dis like, you know, depression, anxiety, those types of things.
and having sunlight all the time can also be disruptive because light is such a strong cue. So the thing is, is they’ve found ways to adapt. So they usually have extremely good blackout curtains so they can create a dark space whenever they want to create a dark space. but I’m sure that has some caveats. You don’t want to go from full bright light to just dark and then you’ll respond normally, right? Like you naturally kind of do need this dimming. and I think they do that to some extent.
And then they use a lot of artificial light, like artificial light boxes that are these really bright lights to try to create that. Now it’s still a struggle and I’ve talked to some people from those areas and they still say, you know, the winter is usually harder. It’s easier to have lots of light and be able to block it out rather than create artificial light, which is much harder. But they’ve kind of found ways to adapt to that. I mean, you got to remember too that the circadian system can run on its own.
It doesn’t need external cues. If I put you in a cave or, you know, one of these environments, which is always dark, you’re still going to have circadian rhythms. And that’s without any types of time cues. The problem becomes is that without light, it’s hard to entrain to stick to exactly 24 hours because none of us are exactly 24. We should a little more or a little less, but not to be exact. Right. And so this is where you actually get into a situation like for people who are blind, depending on biologically how, or if they
Emily (13:53.87)
can’t, you know, if they block their vision with sunglasses or whatever, then they can’t entrain to light either. And what happens is you slowly start to shift, right? Say, imagine your body thinks it’s 15 minutes later every day. You know, after a week or two, your body thinks it’s a totally different time of day than it is. And so the other way that sometimes people cope with this is by taking small amounts of melatonin at night. Melatonin is both circadianly regulated, but it also helps influence your sleep. And when you stay asleep,
And so that can sometimes be enough of an external cue to help synchronize people to keep their behavioral rhythms on track, even in the absence of light.
Isabella (14:35.001)
so crazy. I’m also thinking about like the way that they have casinos with no clocks and like blasting lights all the time. That’s interesting how much… yeah.
Emily (14:40.6)
Yes.
Emily (14:43.966)
yes, it’s completely disorienting. It’s meant to make you not know what time of day it is. Those are not good things for your circadian rhythms. I mean, you can also think about there’s different time zones that are really interesting. So, you know, in the U S we have three time zones. Some are, some regions are better than others, but like China has one time zone, all of China. or if you look in Europe, they’re mainly on one time zone and some of them, you know, 4 PM might be bright outside and some might be pitch black.
Isabella (15:01.339)
Yeah, that’s crazy.
Emily (15:12.936)
And you think about like Spain eating dinner quite late. Well, they have light quite late. So it’s, it’s a different scenario and how you kind of have to live within your environment. You know, people find ways to change. It’s not like people just do things in the darker light and ignore it. People shift, like the culture shift and they kind of account for it.
Isabella (15:12.987)
Sí.
Isabella (15:17.797)
Sí.
Isabella (15:32.857)
Yeah. All right. Well, okay. Can you tell me what it looks like literally in the lab studying this? Like, what are you doing on a day-to-day basis?
Emily (15:46.252)
Yeah. So I used to look a lot more labby when I was working with animals. Now that we’re working with humans, most of the time we’re in an office space. We do have a clinic. So we collaborate with the UCSD Altman translational clinic for, no, sorry, ACTRI, Altman Clinic for Translational Research Institute. And so we’re affiliate members there also. And so they have specific
like there’s a clinic that research nurses where our participants can come in. our, humans that we work with usually come into the clinic there and they can get blood draws or dexas or muscle biopsies or whatever else we need done. And we have them do all their procedures there. And then we communicate with them virtually a lot of the time. So phone, zoom, text. so we’re in, in contact with participants throughout studies, it, it’s usually remote.
And we do see them at their visits. We go and run the visits, but aside from that, we’re in kind of like an office space. But that’s really just the clinical team. The other parts of Suchin’s lab that are more wet lab, it is what you would think of as a traditional lab where you’re, you you have a lab bench and pipettes and chemicals and all kinds of other things around. But my day to day is usually at a desk.
Isabella (17:07.911)
Yeah. And you have also this app that’s a part of helping figure out what’s going on with actual people. Can you tell me about that?
Emily (17:19.672)
Yeah, so the My Circadian Clock app, it’s one of these rare research apps that has been maintained for a long time on both iPhones and Androids. Usually people go with one or the other, they drop it because maintaining an app is a huge amount of work and money. But it’s really been worth it for us. This really all started because when you think about food and nutrition and food logs and when do people eat, no one really knew when. I everyone was looking at
what or how much, but no one really was looking at when you actually ate. And if you said when, it was like breakfast, lunch, dinner or snack, but there was no actual time component to it. Or if there was, it was for, if there were, was just like a few days maybe. And we know humans have crazy amounts of variability in when they eat. And we are also notoriously bad for remembering when we ate. And it became this question of, well, when do we eat?
Can we understand this? And is this even an issue in humans? I mean, we really didn’t know if long eating windows for sure. mean, you have anecdotes about yourself, but you don’t know if that’s really true on a large scale. And so the app was devised to understand that timing. so it took away a lot of the burden of a lot of other food logs where you’re trying to get exact calories or exact quantity and that kind of thing that take a lot of time to enter. And it replaced it with a quick picture or a name or just a name.
you could say burrito if you needed to, which obviously we don’t know what’s inside that burrito, but we know you had a burrito and it timestamps it. And, um, we track this again, not for a couple of days, but usually for a minimum of two weeks. Um, and in some studies over a year, um, so we can understand when people are eating and how that affects them. And so usually it’s not that alone. is, you know, in our controlled trials, we use the app as a way to understand their baseline levels, but then also to implement an intervention.
and communicate with them and monitor them. And then the app is also available for anyone in the world to use. Its main limitation is that it’s in English only at the moment. But it is free to use. So you can track what your rhythms are. You can set your own goals. You can enter health factors if you’d like. So it is a really cool tool that we’re able to provide to people. And it is completely commercial free. We don’t make money off this at all. There’s no ads. It’s a free service to use. So
Emily (19:43.49)
Yeah, if you’re interested, go ahead and download it. My circadian clock. You can find it on your app store.
Isabella (19:48.973)
No ads is very attractive. I like that. Okay, so can you tell me to get into more specific findings about the firefighter study? I know that was a big deal with time-restricted eating.
Emily (19:51.042)
Sí.
Emily (20:03.82)
Yeah. So I mean, shift work is a huge problem. We know that shift work. mean, this is a good example of your behavioral rhythms, throwing off your internal clocks and having negative health consequences. but it’s not like I can just say, well, don’t do shift work. need shift workers, right? the firefighter study became known as the healthy hero study because really most shift workers are, you know, the heroes of our society. They’re protecting us and taking care of us. And, it’s.
It’s a very necessary burden that people carry. We know that it’s linked to increased rates of cancer and almost every form of chronic disease. And these are people who usually start pretty healthy. You know, if you’re thinking of firefighters or nurses or doctors or police officers, they usually start very healthy, but they develop cardiometabolic diseases very early. They have higher risk for cancer. We know that there’s an issue going on there. A big problem in shift work too is that
Only I think it’s 0.0005 % of research, like clinical trial interventions, study shift workers. They are almost always excluded from research. I do this myself because doing shift work is extremely confounding. You can’t just mix that person into the data set as if they’re normal. Normal, quote unquote normal. Obviously they’re a normal person, but they have such a different lifestyle than other people who aren’t working shift work.
Isabella (21:19.911)
you
Emily (21:29.068)
that you can’t just combine them together. So when you’re going to do a shift work study, it needs to be an only shift work study. And even on that level, it needs to be the same kind of shift work. Like you’ve got to control for your type of shift work. and that gets really tricky. The other reason why there aren’t very many interventions is cause what are you going to do? Tell them to sleep more when they have to be awake. Like that doesn’t work. And there have been studies that have just tried to help with sleep hygiene. Like these are good sleep habits. These are things you can try to do when you’re off. These are things to make it easier to sleep when you’re off schedule.
And I was amazed when we first did, um, we did a 24 hour ride along with, um, San Diego fire and they were doing everything, everything, right? Every sleep hygiene thing I could think to tell them they were already doing it. Um, so a lot of these people, they’re, they’ve already mastered all the things you can master, but the problem was you still have these problems. So what do we do? And this is where TRE came in to be super exciting of, okay, I can’t change when you see light. can’t change when you sleep.
I can change when you eat. And firefighters were actually some of our lower hanging fruit there because firefighters generally work either 12 or 24 hour shifts. It depends on the county. In San Diego, they work 24 hour shifts. That’s probably true for about half of firefighters. We also mainly have full career firefighters rather than volunteers, which is very different in other states, but they are allowed to sleep between calls at night.
So in quieter stations, they’re still at least trying to sleep. Now there’s usually a fairly disrupted sleep. Some of them describe it as a very anxious sleep. Like if you have an early flight in the morning and you never really slept well, cause you’re so nervous about missing your flight, that that’s like the best version that they get when they’re on duty. And so it’s not great sleep, but they still get to try to sleep and they still eat their meals during the day. Like they are eating a lunch and a dinner and they might take a nap, but they’re not trying to sleep for most of their day. And so they’re a little bit more aligned.
to begin with, but we knew they were still eating really late into the night. You’d get a lot of things like, you know, it’s a hard thing and how do we cope with hard things? We eat treats. So there’d be brownies brought in or a donut pickup at night or other different things that kind of cope with it. And so we knew they were still eating late. We knew they had this issue. like, well, what if they just didn’t eat at night? You know, what if they had this like 10 hour eating window, nothing extreme. It’s like a nine to seven is what most people picked. allow them to personalize it. And could they do that?
Emily (23:54.818)
And we did allow black coffee whenever needed. We encouraged them to consume it during their eating window if they were able to, but if they needed it to go for it. And we found it was very feasible. They were able to do it. They felt like they had more energy. A lot of them were very surprised. like, I really didn’t feel hungry. Like I feel better now than I did before. And a lot of the participants in that study were healthy to begin with, and a lot of it was feasibility. But in the
groups that we had people who did have, you know, elevated glucose levels, we saw significant improvements in that group. And the ones who had elevated LDL or like bad cholesterol, they significantly improved as well. And even in the full population with mainly healthy people, we also saw reductions in some of these other cardio metabolic markers like VLDL, which is very low density lipoprotein, which is what forms these plaques that lead to things like heart attacks and strokes.
Because they they’re these big kind of lipids that fill up and get bigger and bigger when they fill up with Triglycerides we actually found those shrunk in those people even within the healthy participants and so that was super exciting to see like one this is doable, you know, even if you’re working a 24-hour shift eating within 10 hours is a very possible thing to do and They actually feel better on it. And then the ones who have room for improvement are doing better And so that was our really our first
kind of toe into shift work and it really kind of has become a bit of a passion and I’m running my own study now on night shift nurses and nursing assistants who are working these night shifts that are 7 p.m. till 7 a.m. and that is trickier, right? Because they’re trying to sleep during the day, they don’t get to sleep at all at night, they’re awake the entire time and it’s a totally different challenge and so it is a bit of a different study as well. But we’re trying to see, know, is it possible and if it is, can it help?
Isabella (25:48.071)
And so this isn’t related to time restricted eating, but what is your stance on napping?
Emily (25:53.778)
I think napping is your body telling you you don’t have, you need rest, right? And if you’re able to get enough sleep at night, most people don’t need a nap. if you’re able to consolidate your sleep, but there are times where you will need to nap. think everyone’s been sick and needed an extra nap because your body was tired, right? If you are consistently not getting enough sleep, maybe you need a little more sleep than someone else. You know, for adults,
Isabella (25:58.469)
Mm.
Emily (26:18.838)
It’s pretty well known. mean, the general standard is seven to nine hours. And some people feel great with seven hours and some people feel awful unless they get a full eight or eight and a half. Right? So it’s a bit relative and you kind of got to know what’s right for you. But say you’re even in your seven to nine. If you feel, if you’re someone who really needs eight or even seven and a half, and you’re always getting seven, you’re going to kind of have this chronic buildup of, you know, a little bit of sleep restriction. Now it’s not severe sleep restriction.
But that can build up and a nap is usually saying I need rest for whatever reason it may be. There could be a homeostatic drive like you had a really super intense physical or emotional or something event, or it could be this kind of buildup over time of I am just really tired. And so I think if you are capable of napping, probably means you need to nap. Now on the other side of that, I wouldn’t overnap if you don’t need to, because if you nap for a lot,
during the day or later in the day, then you’ll probably have a hard time sleeping at night if you’re napping when you don’t really need to be napping. And some people can just fall asleep whenever and they would have also been fine being awake. There’s a lot of personalization in that. But I think if you find yourself being really tired,
Especially short naps can be quite rejuvenating of like a 20 minute nap or a 30 minute nap. think when you get into the multiple hour naps, either you have severe sleep restriction or you’re sick or something else is going on. but you shouldn’t need multiple hour naps every day, unless you’re a toddler or younger, you know, but yeah, naps can be a wonderful way to help yourself catch up on a little bit of sleep when you need it.
Isabella (27:54.127)
Yeah, I’ve heard that like 20 to 30 minutes is the sweet spot and then there’s the like disastrous four hour, you fall asleep in the afternoon, you wake up and it’s dark and you’re disoriented. Like the worst ever.
Emily (28:00.939)
You
Emily (28:06.606)
Yeah. I mean, if you’re able to sleep that long at a time where your body normally doesn’t sleep, you probably really needed it. But the problem is then it’s like you end up staying up super late and you can get further off schedule. so more than anything, you know, just like with food, having a really consistent sleep and wake time, just like a, you know, start and end of eating time is super helpful. Um, and there’s more and more evidence coming out about sleep variation being a problem.
Isabella (28:13.104)
Sí.
Emily (28:32.638)
And so the more consistent you can be, the better it is. And usually naps are more likely to mess with that than not. But if you need a 20 minute nap in the afternoon and it’s not messing up your ability to fall asleep at the proper time to get enough sleep at night, then I don’t see a problem with it. If you have that ability to do so.
Isabella (28:48.593)
Yeah. Yeah. Okay, have another sleep question, then we’ll go back to Tiare. Are early birds and night owls a real thing?
Emily (29:00.396)
Yeah, so there’s this phenomenon called chronotype. And chronotype is really how you interact with your environment. And this comes back down to your even molecular clocks in individual cells. So the amount of time that it takes for one full cycle of these transcriptional translational feedback loops, which sounds really complicated, but just say one cycle of these proteins interacting with each other is about 24 hours. And if you have shorter than that,
then you’re an early person. Or even if you’re on the closer to 24, the average for humans is like 24.15 hours as our period. So most of us are slightly longer than 24 hours. And there are the shorter your period is in your internal clocks and really at the level of your central clocks in your brain.
The shorter the period that is, the earlier of a person you get because your relationship to your environment is that maybe you wake up before the sun comes up or right when the sun comes up rather than a little bit after the sun comes up. So you think about it as like a relative phase to external cues and the shorter your period, the earlier you wake up, the longer your period, the later you wake up. This isn’t even consistent throughout your lifespan. So when you are younger and much older, you actually have a slightly shorter period.
when you’re going through puberty, your clock starts to delay. So this is why, I don’t know, a lot of teenagers like to sleep in is because they actually probably have a later clock, at least at that time. And it seems like women come out of it a little bit sooner than men. Like women in their early to mid twenties are waking up earlier again and are able to kind of shift a little earlier, whereas it takes men a few more years. There’s some debate about how much of this is just behavioral, right? Like how much are we artificially?
keeping ourselves awake and would have been able to fall asleep if we turned off lights and turned off food and turned off stimulation. There’s actually a really cool study from Ken Wright’s group in Colorado that took people camping, mainly like college-aged students. And so the only light that they had was natural light or fire light. And almost everyone became an earlier version of themselves. So a lot of this probably is somewhat related to these external cues that we can adjust, you know, with
Emily (31:16.844)
you know, real diligence of turning things off and that can definitely help. But there does seem to be this trend overall in many different societies, not just in the U S but internationally that we’ve become a little bit later version of ourselves and then start to become earlier again. but yes, there are natural early birds and there’s natural, owls and there are some very rare, but true circadian mutants where you’re these extreme early or extreme late. And those
are not behavioral at all. Those are actual mutations to the clock, which make it extremely hard. And honestly, those types of people usually do much better on a shift work schedule that can adapt to when their body would normally want to be awake.
Isabella (31:59.623)
Yeah, definitely the camping thing makes a lot of sense. feel like the best sleep I ever get is in a tent on the ground. It’s not even that comfortable, but it’s so good.
Emily (32:07.536)
Hahaha!
Yeah. Or just a big power outage. know my first year in grad school, there was a giant snowstorm before the leaves had fallen off and power was out for weeks. And when you have no entertainment, you do go to bed early. You know, you go more with the light and then you’re more rested. And so you wake up a little earlier. So I think there is a lot of behavioral things that you can do to try to help yourself be an earlier person, because so much of our, our reasons why we stay up are artificial, you know, and we kind of.
Isabella (32:14.287)
Sí.
Isabella (32:25.315)
Sí.
Isabella (32:40.4)
Sí.
Emily (32:41.004)
are pushing too much into our day a lot of the time. But it does seem like there’s an underlying component that does change throughout life. And there definitely are early and late types. But you can adjust it to a certain extent.
Isabella (32:56.315)
Yeah. Okay, so back to time-restricted eating. So you’ve made all these really interesting findings about shift workers. What about the rest of us? What are the recommendations for an average person?
Emily (33:11.446)
Yeah, so actually most of our work is in non-shift workers. And we mainly started with the focus on individuals with cardiometabolic diseases, mainly because that was where a lot of the findings were in the rodent studies that came out, you know, looking at liver function or inflammation or glucose regulation. And so that’s kind of where we started in humans.
But we’ve seen it now and you know, it’s not just our lab that studies this anymore. Many, many labs across the world are studying this. and the recommendations for a shift worker are not seem to so far be the same. which is your, whole goal of it. And you really step back and say, when am I trying to eat? It’s allowing yourself to wake up and not eating exactly when you woke up, especially if you’re waking up with an alarm clock, right? It’s about allowing your body to anticipate, which is what the circadian system does. It anticipates what your body’s going be able to do to prepare for it.
So it’s about eating when your body knows you’re going to eat and importantly, when you’re awake and active and in the light and then allowing yourself to stop eating, but you know, at least a few hours before you go to bed. So what that usually looks like for people is somewhere between an eight to 10 hour eating window. So that might look like something like 10 to six or nine to seven. think 10 hours is usually completely adequate for getting, you know, at least 95, if not more.
all of the benefit 95 % or 100 % of the benefits that you’d get from an eight hour window. because less than that, I think you are tapping into caloric restriction, which can also be helpful, but is separate and can be additive, but it’s not necessary for all these other benefits that we’re seeing. And I don’t think it’s necessary from a circadian point of view, but it’s important that it’s consistent. So if it’s nine to seven, it’s always nine to seven. It’s not, ate an hour later today. So I’ll eat an hour later tomorrow. That’s not what we’re looking at.
we’re looking at a consistent window that can reinforce those rhythms that your body can anticipate and that you’re able to process. mean, our body is filled with incompatible events. When you’re sleeping, your body is preparing you to fast. So if you eat when your body thinks you’re not eating, things don’t work right. And you’re not able to process things properly. so keeping the things happening when they should be happening and allowing them to not happen when they shouldn’t happen is super helpful to your body. So,
Emily (35:33.966)
Find a 10 hour window that works for you. Make sure you can fit in any important meals, like a family dinner or something, you don’t want to, you know, make sure it’s feasible and then try to stick to it. And I, know, if you find you have a really long eating window right now, you can go, you know, a little bit shorter at a time. It takes a little bit of time to, it’s up to about two weeks for your body to kind of get used to your new time.
So if you’re at like a 16 hour eating window right now, don’t go to 10 tomorrow. I think that’s a little insane unless it’s just like wine or coffee that you’re cutting out. But if it’s actually meals, start moving them by a half hour on each side. I also think one of the common misconceptions that you’re like going to be skipping meals or starving yourself, and that’s not the case at all. It’s, really about maybe delaying your first meal a little bit and advancing your dinner and just making sure you’ve got like at least an hour after you wake up for your body to get ready to process everything and see light and be ready.
And then about at least three hours before you go to bed that you stop taking in any other calories or caffeine or anything like that. I caffeine a little earlier because it has a quite a long half life. but to make sure your body can kind of cool down and be able to sleep. cause even if you get into bed, but you just ate something, even if you fall asleep, which might be harder to do, but even if you do fall asleep, you’re not going to get as restorative of a sleep. If you just ate, and this is, this is a common problem when you think about alcohol, it’s like you’ll fall asleep, but the quality of sleep you get is usually quite poor.
Isabella (36:56.871)
So bad.
Emily (36:57.728)
And so it’s a matter of letting your body function the way it’s supposed to.
Isabella (37:02.727)
Yeah. So I have a question based on my lifestyle. I usually, find that I don’t eat breakfast for a while after I wake up, but I do wake up and have that coffee. But I like to have like an oat milk latte or a coffee with a little cream. Does that immediately not count because it’s calories and not black coffee? So that messes up the window.
Emily (37:22.604)
Yeah. Yes, that does mess up your window. I think there’s some things you can do for that though, is, know, when we usually, for most people, we push coffee into the eating window. Also, we really only allowed coffee in shift work studies. or if someone really, the only thing they need is black coffee. Well, sometimes allow that most of the times we don’t. a lot of other researchers though, I do know also do allow black coffee or tea. and that gets kind of complicated, but if it has
five calories or less. something like a cup of coffee or, you know, a tea with lemon or something like that, but no sugars, no artificial sweeteners. Artificial sweeteners have lots of impacts on our metabolism. Even if they don’t have calories, they do impact things. They have to be digested. There’s a whole other slew of things that have to happen. so my recommendation is to try to switch to hot water, which I know sounds overly restrictive. I was surprised cause I used to do coffee first thing when I woke up and I
didn’t usually use creamers, was on a black coffee kick, but I was used to getting coffee first thing. And I found switching to hot water was shockingly helpful of like, it still gave me my hot drink. Like it ticked a lot of boxes that I thought I was going to be totally underwhelmed. And it wasn’t some crazy like four hour shift. It was like an hour later or something like that. And so I would have water, it’d still be warm. It would kind of give me my behavioral habit that I liked. And then I would just have coffee a little bit later.
Or if you’re having, you know, you want a latte or something added to your coffee, it’s a try to stick to black coffee until you get to your eating window and then have, you know, a cappuccino or whatever it may be. but yes, if you’re having calories, it definitely will break the fast. Some people don’t add sugar, but they had like collagen or something like that. Yes. That’s also breaking your fast. and so yeah, it’s something to consider same, you know, in the inverse at night is like a glass of wine after dinner or something. It’s like, yes, that’s still counts. So.
Isabella (39:11.623)
you
Emily (39:19.606)
It’s a matter of trying to have those things with your meals instead of before or after.
Isabella (39:19.643)
Sí.
Isabella (39:25.627)
Yeah, that’s interesting about the hot water too. I was reading recently that that’s like good for your digestion, which I don’t know if that’s true, but starting off the morning with hot water, maybe I will try it.
Emily (39:39.276)
I mean, a glass of water is generally a good thing. know, like sometimes we tend to eat more or do other things just because we’re dehydrated and, know, just drinking enough water is important and it’s a great way to start your day. I don’t know if it has to be hot or not, but I found because I was replacing a hot coffee, the hot water was more satisfying.
Isabella (39:42.715)
Sí.
Isabella (39:55.911)
Sí.
Alright, so let me see for my questions. Yeah, guess earlier you were saying that you were thinking in grad school, I think it was, about, you know, five years into the future, what you want to know and trying to kind of shape and think about your research in that way. Do you still think about it that way? Are you still thinking like, what would I like to know in five years?
Emily (40:25.42)
Yes, a hundred percent. And partially is we have to, know, a clinical trial takes about five years to run. And that’s how long our grants are for. Like when we write a clinical trial grant, they’re usually a five year grant, sometimes slightly shorter, but usually not. so it’s usually about five years when you’ll get your answer and you got to think about what’s still going to be novel. Then what questions are we, how’s this going to help us? How’s this going to work with what we know? What gaps can we fill in? And also like, what’s the next thing?
And so, yeah, I’m kind of always thinking on a five year scale. And I think, you know, where that’s going more now is, you know, time restricted eating was tapping into one input of the circadian system. And now I think it’s becoming more of this multimodal. What if we combine light and food and timing of exercise and social cues or, you know, all these other things and sleep hygiene. And what if we do it as a full circadian optimization of your lifestyle and
It also helps probably a wider range of people because you now are getting, know, maybe you’re good at this, but you’re not good at that. And we can fix this portion of it. And so we’re actually running a pilot study right now and working on a grant for a larger study to really look at these multimodal interventions for improving health span and aging. Even in relatively healthy individuals, like as we age, we naturally kind of
you know, have health issues arise. And so it’s a matter of saying like, you know, the circadian system is just as such a core part of how all life works. You know, we’ve been talking about humans mainly, but all life forms have circadian rhythms. And when you support those rhythms, you’re going to be a healthier, better version of yourself. And so really it’s finding like, how can we support that? And obviously there’s all these specific challenges like shift work or
or different or like, you know, when you’re pregnant or when you’re breastfeeding or all these other things that I think will have various, have specific interventions or nuances. And I think, you know, humans are obviously so different. And so what works for one person may not work the same for another. So I think there’s so much to figure out there, but I do think it’s transitioning to this more multimodal approach rather than only affecting one thing. Like we can look at them independently and we can look at them together and see how you can kind of.
Emily (42:53.624)
really just optimize someone’s circadian rhythms.
Isabella (42:57.019)
Yeah. Is there something very specific that you’re most excited about in the next few years? Or is it really just like this big zoom out?
Emily (43:07.362)
Yeah, no, I mean, I think I’m really excited about the studies we’re writing grants for right now on specifically some of the aging work. And we’re also competing in XPRI’s health span as, and this is the studies we’re running for that. And so I think that’s been really exciting to see some of those changes and, you know, especially coming from animal work, switching to humans. One of the coolest things is even if you’re, know, the overall thing didn’t come out as significant or different as you thought.
Every time you see one participant get healthier, you’re like, that person is a healthier person now because of this research. And that’s, that’s really cool. And so we’ve seen so many people improve their lives and be such healthier versions of themselves that it’s always very rewarding. the other projects I’m interested in one started as a, kind of a passion project with a friend. So when you go to conferences, especially this one circadian conference, you actually really get disrupted for them. So one, you, you change time zones.
But also this conference specifically, the poster sessions go super late. People are socializing with each other really late and drinking and we knew we’re like, we’re messing ourselves up so much. should setting ourselves. And so we did, we ran this little trial called disrupt and it was understanding how, you know, traveling, you know, to a new time zone and then messing up your schedule affects your glucose regulation, affects your sleep cycles, all those things. And we’re already finding like.
big effects on how you process glucose. And so one of the other things I’m really excited about is getting more into this understanding of jet lag and travel and how we’re directly affected in that acute scale for that, you know, frequently when you’re going on a trip, it’s three days, maybe three days to two weeks or something like that. And what’s happening to you? How can you process glucose differently at different times of day, depending on if you advanced or delayed your time. and I’m really excited about that. And,
going to be putting in grants this year to try to do bigger studies on that because that I think really has the power to say, okay, if you’re traveling this way, like wait to have your sugary thing until this time, because if you do it early, it’s going to really hurt you. But if you wait, you’ll be okay. Some of these things where it’s not, don’t eat the cake, it’s eat the cake at the right time. And I think that’s so much more feasible than just full on restriction. And can also potentially really help people, especially, especially frequent travelers or people are having,
Emily (45:28.576)
obviously people in aviation and pilots and flight attendants and things like that, but also just everyday travelers that, you know, if they are pre-diabetic or diabetic, these could have a much bigger effect for them. And then just making sure we, you know, we know how to keep ourselves healthy throughout our lives. and time zone changes is a big part of that, that we know it doesn’t feel good. Everyone knows jet lag is annoying, but like, how do you actually deal with it? And what can we actually do to diminish those effects? And so that’s been kind of a fun.
passion project that I’ve also been working on that I’m excited to expand.
Isabella (46:01.723)
Yeah, and talking about the ways that going to a conference is messing up your circadian rhythm is a good segue for my question. How you’re, with this kind of research, are you like thinking about yourself and how your circadian rhythm is working like all the time? Are you constantly like, my God, I’m not optimized. Like, what am I doing?
Emily (46:23.406)
Yeah, I mean to some extent, of course, yes and no. So I definitely will, you know, if it’s really late or I’m staying up later than I should or I’m getting light later or I’m eating later, I know it’s not good for me. even my husband now will be like, nope, it’s too late. It’s closed or whatever. And we’ve all kind of adopted it and we’ve all, think,
Isabella (46:41.987)
Sí.
Isabella (46:46.809)
you
Emily (46:52.544)
everyone’s really bought into it, not just because of the research, but even just anecdotally feeling how they feel different if they eat late or not eat late. and so we’ve all been doing it for so long that, we’re kind of aware of that, a little bit all the time. And we also know when to give ourselves that grace and give ourselves a cheat day or whatever, because, you know, we’ve got two kids and schedules are crazy and sometimes are easier than others. But I think we all kind of just very much have.
Isabella (46:57.04)
Sí.
Emily (47:19.992)
personally felt the benefits of it. So we all try to stick to it as much as we can and try to help each other through it if someone else is struggling. But it helps when the whole family works together on it. It’s not nearly as hard. It’s when someone else starts making popcorn. You didn’t think you were hungry, but then you smelled the popcorn and now you want popcorn. Or someone’s having a treat and you didn’t need it, but now you want it. And then it gets harder. So when we work together, it’s a bit easier on that.
Isabella (47:28.39)
you
Isabella (47:47.333)
Yeah. So with this like all-consuming 24-hour circadian rhythm thoughts in your head, do you have time for any non-sciencey activities or hobbies?
Emily (48:01.416)
yeah. So, I mean, the nice thing about sticking to a consistent circadian pattern is once you’re consistent, things actually fall into place a lot easier, right? It like having any kind of structure. actually get a little calming to have some structure there. It’s less erratic and it also feeds back on itself. So your hunger goes away at night and you don’t want those things at that time of day anymore. But yeah, so I’ve always had, art has always been a big influence in my life through.
Isabella (48:13.735)
Sí.
Emily (48:28.984)
Tap dance was a passion of mine when I was younger and continued to do through grad school. but also just like visual arts and painting and actually within the past few months, I’ve gotten back into painting a lot more and it’s been a lot of fun. and now my daughter’s almost six and, she, she’s been, she’s fallen in love with art too. So we paint together a lot and then we try to travel and, go on hikes and go to the beach and all those fun things. And luckily being in San Diego, you know,
We can just drive to the beach and paint looking at the ocean, which has been a huge luxury. It’s just so nice. I actually did that yesterday with my daughter and it was lovely. so, yeah, so, you know, some paints and, just carry the bag out to the ocean and sit down and paint. That’s, that’s my, fun little relaxing recharge moment.
Isabella (49:02.065)
So nice.
Isabella (49:07.675)
Sounds so good.
Isabella (49:21.543)
So nice. That’s part of why, too, I was attracted to Salk as, like, the marriage between art and science. And I find that, like, every scientist I talk to is like, yeah, I also, like, play saxophone. I also, like, dance. I also do this. And I’m like, everyone’s an artist. It’s beautiful.
Emily (49:42.646)
I mean, art’s just like, it’s another core part of being human. think it’s just a way you express yourself. And there’s so many different types of art, right? You could write or sing or draw or dance or whatever it, whatever it is. But, if you’re, you know, we all lose time for it at some point and then finding again can be, can be really nice. But yeah, think Salk does a nice job of highlighting that interconnection between art and science and creativity and, and.
Isabella (49:51.718)
Sí.
Emily (50:11.544)
thinking big and what doesn’t exist yet and trying to figure things out. I think art and science overlap a lot more than most people realize. And so it never surprises me when scientists are also into art because I think they have so much, there’s so much overlap there.
Isabella (50:24.665)
Yeah, totally. Okay, now I’m going to ask my school related questions.
Emily (50:31.768)
Okay, I also have a meeting I have to get to, so we kind of need to finish up, if that’s okay.
Isabella (50:35.331)
Okay. yeah, it’s at 1 30.
Emily (50:39.744)
Yeah, I can be a couple minutes late, but I need to wrap up.
Isabella (50:42.351)
Okay, it’s okay. It’s okay. I think that I’m actually gonna… It’s honestly fine because I think that we were gonna try to do it as a September episode and then I think that with the year of brain health stuff, it’s gonna be potentially a next year episode. So I can always just get you on for like 20 minutes at some point later this year. So, all right.
Emily (50:46.698)
Okay, I can do like one or two more, but yeah, let me just text them.
Emily (51:05.388)
Okay. Okay.
Either way is fine. yeah, if you want to just like set something else up, this isn’t hard. We can do something next week or something if you want.
Isabella (51:16.997)
Yeah, sure. All right, well, I will let you go then. Thank you so much. This was great, and I’m excited to put together the episode.
Emily (51:25.782)
Awesome. Yeah. Just email me for when you want to meet up again.
Isabella (51:29.383)
All right.