Subscribe
Share
Share
Embed
Save 20% on all Nuzest Products WORLDWIDE with the code MIKKIPEDIA at www.nuzest.co.nz, www.nuzest.com.au or www.nuzest.com
Curranz Supplement: Use code MIKKIPEDIA to get 20% off your first order - go to www.curranz.co.nz or www.curranz.co.uk to order yours
NZ listeners - save 10% off Calocurb by using the code Mikkipedia10 at www.calocurb.co.nz
Curranz Supplement: Use code MIKKIPEDIA to get 20% off your first order - go to www.curranz.co.nz or www.curranz.co.uk to order yours
NZ listeners - save 10% off Calocurb by using the code Mikkipedia10 at www.calocurb.co.nz
In this episode, Mikki speaks with Hannah Cabre from Pennington Biomedical Research Center about energy expenditure, body composition, ageing, and what really happens to metabolism through midlife and beyond with a focus on sex differences.
Hannah’s work uses doubly labelled water data, considered the gold standard for measuring total daily energy expenditure in real-world conditions. This allows researchers to understand what people actually burn across the day, beyond estimates from fitness trackers, calorie equations, or short-term lab measures.
Mikki and Hannah discuss the idea that metabolism is “stable” from 20 to 60, whether menopause uniquely affects energy expenditure, why body fat can increase even when scale weight stays the same, and why preserving fat-free mass becomes increasingly important with age.
This is a nuanced, evidence-based conversation for anyone interested in metabolism, midlife body composition changes, and what ageing really means for energy needs.
Hannah E. Cabré, PhD, RD, is an Assistant Professor at Pennington Biomedical Research Center and Director of the Aging, Gynecology, and Endocrinology Laboratory. Her research focuses on how female sex hormones influence nutrition, health, performance, and body composition across the lifespan, with a particular interest in sex differences during ageing.
Hannah’s work explores the importance of skeletal muscle maintenance for long-term health, especially during the menopause transition, and how lifestyle interventions may help mitigate age-related changes in body composition and healthspan.
Creators and Guests
What is Mikkipedia?
Mikkipedia is an exploration in all things health, well being, fitness, food and nutrition. I sit down with scientists, doctors, professors, practitioners and people who have a wealth of experience and have a conversation that takes a deep dive into their area of expertise. I love translating science into a language that people understand, so while some of the conversations will be pretty in-depth, you will come away with some practical tips that can be instigated into your everyday life. I hope you enjoy the show!
00:00
Hey everybody, it's Miki here. You're listening to Mikkipedia and this week on the podcast I speak to Hannah Cabre from Pennington Biomedical Research Centre about energy expenditure, body composition, aging and what really happens to metabolism through midlife and beyond with a focus on sex differences. So Hannah's investigative work using large databases
00:28
looks specifically at doubly labeled water data, considered the gold standard for measuring total daily energy expenditure in real-world conditions. This has allowed Hannah and her colleagues to understand what people actually burn across the day beyond estimates from fitness trackers, calorie equations, or short-term lab measures. Hannah and I discussed the idea that metabolism is stable from 20 to 60, where the menopause uniquely affects energy expenditure,
00:58
why body fat can increase even when the scale weight stays the same, and why preserving fat-free mass becomes increasingly important with age. So this is for all of you out there who really love a nuanced evidence-based conversation about metabolism, midlife body composition changes beyond what you hear out on social media, and what aging really means for energy needs.
01:25
It was really great to sit down and chat to Hannah about this. And she is a prodigy of Dr. Abby Smith-Ryne. So really great to see emerging researchers in this field. So Hannah Cabray, she's PhD and registered dietitian. We speak about this on the podcast. She's an associate professor at Pennington Biomedical Research Center and director of the Aging, Gynecology and Endocrinology Laboratory.
01:53
Her research focuses on how female sex hormones influence nutrition, health, performance, and body composition across the lifespan with a particular interest in sex differences during aging. Hannah's work explores the importance of skeletal muscle maintenance for long-term health, especially during the menopause transition and how lifestyle interventions may help mitigate age-related changes in body composition and health span. So I have a link to Hannah's public page
02:22
on Pennington Biomedical Research Centre website in the show notes. So check out that for any and all of information related to Hannah's research. Before we crack on in though guys, I would like to remind you that the best way to support this podcast is to hit the subscribe button on your favourite podcast listening platform. That increases the visibility of Micopedia in amongst literally thousands of other podcasts out there. So more people get to hear from the guests that I have on the show.
02:51
like Hannah. Alright guys enjoy this conversation.
02:59
Hannah, thank you so much for taking the time with me this afternoon to chat about your research and particularly this paper that I saw you as, I believe, lead author on actually. And I'm always interested when I chat to um other professionals who, you're a registered dietitian, you've gone down that route, but here you are in research. So can you kick us off by telling the listeners, give us a little bit of your background and
03:29
particularly what you're working on and how you sort of got into the Pennington Biomedical Research Center. Yes. Well, thank you so much for having me. I'm very excited to be a guest today. And as you mentioned, I am a registered dietitian. So that is what my main background is in. And part of becoming a registered dietitian in the US is the internship that you have to do. And so I attended Florida State University where I did a master's degree along with the internship.
03:59
And so I started becoming more active in research at that time period and just really fell in love with the crossover between how we can take the evidence-based principles of being a riser dietician and then actually be the ones like provide that information for practitioners.
04:18
So I decided to pursue a PhD and since then I've been doing my postdoctoral fellowship at Pennington for the past three years and I'll be transitioning to faculty actually next month. And here I've been really able to establish myself in more of the nutrition and kind of aging realm. So the paper we talked today is one of those looking at differences, sex differences in aging and how that affects energy expenditure.
04:44
And I'm especially interested in women's health research and how we can optimize healthy aging in women. Hannah, what drew you to this field? Was that what your PhD was in as well? So my PhD was in exercise physiology. And I chose to do exercise physiology mostly because I felt I had a very strong nutrition base.
05:05
And this is just another added benefit of understanding the physiological systems and how we can optimize health with exercise and partner that with nutrition. And I think that crossover has been really beneficial for my research. The research I did in my PhD was a little bit more applied. We did a lot of supplement research, a lot of exercise interventions with supplements.
05:28
And since transitioning here, it's been a little bit more clinical research based. And I think that all of the skills I learned have been really helpful in learning how to apply this to more populations that have special interests like individuals with obesity, individuals with high blood pressure. So those are some of the populations I'm specializing in now. I love that. And I do because I have a background in nutrition. That's where my postgraduate degrees are as well.
05:57
And I really felt it's interesting with nutrition. I'm not sure what it was like for you going through, but you learn a lot about nutrition specifically, but not a ton on sort of physiology. I mean, your dietetics route would have of course given you more insight maybe into food, cetera. But that's such a lovely crossover to actually understand how the body utilizes nutrients, not just sort of learn a little, I don't know. I did feel like,
06:25
nutrition as a degree wasn't even the science, the, you know, the science of nutrition didn't actually teach you a lot, but potentially that's just an undergraduate degree, you know, in itself. I think there's a nice like crossover with understanding how the body systems break down the nutrients, but not necessarily as much of the translation as you said, between like how those are utilized when you're exercising or set rest. So that was a good added benefit to understand.
06:54
Yeah, nice one Hannah. now you work with, and I wrote it down, but it actually stood for the IAEA, which is the International Atomic Energy Agency Database, which sort of sounds a little bit like, what am I thinking of, like NASA or something, which it is not. So can you explain to the listeners, this is an international, a massive international data set. Can you give the listeners
07:23
a little bit of detail about what it actually sort of, what kind of data you're working with Hannah and in fact, what it's like working with the data that's been collected by researchers all over the world. Yes, so the IAEA for abbreviation is one of the largest databases, it's the largest database in the world looking at measures of doubly labeled water. And doubly labeled water is really special water that has
07:52
uh the ability to kind of track throughout the body. It has an isotope on it so you can track how long it takes to excrete that over time. And with some calculations, we can estimate how much energy is being expended. And so it's a very uh gold standard method for energy expenditure within the field. And we can really get a great picture of what that looks like across different demographics. And so there was a
08:21
to kind of join all of the different groups across the world who are doing research with doubly labeled water and be able to contribute those data to just a one kind of pool. So the database itself is very diverse. A lot of different studies have been a part of it. So it's not one study that is just over every other country, but any study that utilizes doubly labeled water can be submitted.
08:50
So we have a huge data set of thousands and thousands of people across the globe that are included in this data set. So it's a great opportunity to investigate some questions about energy expenditure. There's children, there's elderly individuals across the ages. And so it's just a very great um diverse population. So working with that data has been really fascinating because it's just such a
09:18
diverse sample and it can help us answer questions at a larger scale than what you would be able to just at a one site research center. And there's some challenges with it just because of that diversity, but being able to look at the whole representative population of a global sense allows for really great representation that I don't think we often get in research. I love that Hannah. how does it, you know, people are
09:45
particularly people who listen to this podcast and I don't know what your social media feed is like, but mine is filled with uh people with questions and comments and opinions on energy expenditure, the best way to track it, the best way to measure it. How does doubly labeled water, you said it was gold standard. Do we have a sense of how the fitness trackers or even the metabolic cart sort of stack up compared to doubly labeled water?
10:16
Sure, yeah. the metabolic cart, for example, is more of an indirect method. W labeled water is still considered indirect also, but because it's an isotope that you consume, you drink the water and then you collect urine over a certain number of days to be able to add it to that calculation. It provides like a little bit more of a longitudinal sense. So usually seven to 14 days of collection occurs.
10:42
where the metabolic cart you're measuring for about 30 minutes at rest. So the time period that you're measuring is much shorter and can be often um influenced by a lot of different factors. So how well you slept the day before, if you exercise, if you ate anything, if you're stressed. So a lot of those measures can be a little bit more influenced in that sense. And then if you have like activity watches, those will often provide estimates also.
11:11
And that is using your kind of activity levels and how active you are as an estimate based off of your age, your height, your weight, your sex. Sometimes race will be included in that as well. So the doubly labeled water kind of gives just your total daily energy expenditure. It also includes your physical activity level. So it's just a great measure that kind of encompasses how much energy is being expended across those days.
11:38
where the resting metabolic rate is only looking at how much energy you expend at rest. So if you wanted to kind of say, okay, I'm an active athlete, I do a lot of exercise, how many calories do I actually need? You're estimating it based off of an activity factor. So that is some of the bigger differences between those two indirect measures. So it's a kind of more global method. And often the resting energy expenditure is used with total daily energy expenditure.
12:08
um And that way you can kind of get that activity aspect with total daily energy expenditure, like how active you were within those time periods. So it can be a great measure to kind of combine them with. Yeah, do we get a sense on like how accurate some of these things are? And I don't know if this even, this might be sort of beyond the stuff that you look at day to day, but I'm curious as to sort of your opinion, given that you work with the, um in the work that you do.
12:37
Yes, I think it's very accurate. So we have some great studies here at Pennington that we work with, the United States military, for example, and those data are just um much more accurate than if you are looking at an energy equation, for example, or doing resting metabolic rate with the energy expenditure equation too. So those will often underestimate compared to total daily energy expenditure. So I think it's
13:07
very representative of just all of the systems that are going on when you're looking at how energy is expended. You have sleeping energy expenditure, you have resting energy expenditure, you have thermic effective food. All of these are components of energy that are estimated with doubly labeled water. So it's often more accurate in that sense as well. Nice. I remember when I was working as a researcher at Auckland
13:35
at AUT University actually, and we have a professor there and she was using doubly labeled water. And she said, the actual, the water itself is fairly inexpensive, but the analysis is where the cost sort of comes in. Is that still true, Hannah? Yes, yes it is. So the water itself is not um as expensive, but having to use your mass spectroscopy to...
14:01
Analyze it is a little bit more intensive. It's more labor intensive and there's just a lot of components that go into it. So yes, still that aspect is where the costs come in. Oh, nice one. So before we crack on into your, I guess, the findings, can you give us a little bit of detail on what you stood out looking at? You mentioned six differences in aging. Can you talk us through what you did and also, of course, what you found?
14:31
We were interested in looking at how the time periods in a woman's life, so premenopause, perimenopause, and postmenopause, may affect energy expenditure different than men because women will often go through perimenopause within the 40s to 50s age range, so that mid-life time period. And the loss of estrogen has been associated with changes in body composition.
15:01
and changes in potentially energy expenditure is still kind of an unknown uh aspect of this. And so we were interested to see if there were these sex differences. There is a very large paper and study done on this data set by Dr. Hermann Ponzer that demonstrated across the lifespan of both men and women that about age 60 is really when you start to see this decrease in energy expenditure.
15:29
And so uh when you look at the data kind of collated together without these different groups, we were wondering if there could be differences that were being lost in that way. So that was kind of the initial question that we had to say, if we do break this up into age groups, would we see these differences? We did not have any hormone data within this population or.
15:55
measurements of menopause status. So this was not like a questionnaire that was done across the entire data set. So we really were just relying on our age groups with this. So that is a little bit of a limitation within the data set itself. But I still think that using the age ranges that we did, being really representative of what we see kind of in the literature, stayed true to what our original question was. So then some of the results we saw were
16:24
Very in line with the overall analysis from Dr. Poncer, but we saw that there were really big changes in body composition in women within that mid-lifetime period. So what we would kind of expect to see was this increase in fat mass and a decrease in lean mass. uh Total body weight did not change that much over the female lifespan. So even though women were staying pretty weight stable.
16:51
we saw that that contribution of body composition was changing. So women were losing more of that lean mass, gaining more of that fat mass. And that was happening at kind of a faster rate than what we saw within the males. And so that was a really interesting finding. And when we think about kind of energy expenditure, our lean mass is a big contributor to our energy expenditure. So when we looked at
17:17
the analysis we knew that we needed to kind of consider that within the statistics. And so when we considered for body composition, we didn't really actually see too many sex differences between the two, which I think paints a picture of how important these changes in body composition can be, since when you kind of account for that, there aren't those sex differences.
17:40
m And we did see that energy expenditure decreased over time. So the older groups in our, which was 55 to 70, saw a decrease in their energy expenditure. So in line with kind of that 60-ish inch range for that decrease. Okay. So your findings, they add to Ponce's sort of findings or summary, if you like, right? They're not in, are they?
18:10
they're not challenging what that other large study found, but they're just adding a bit of nuance, would you say? Yes, absolutely. So we um definitely agreed with Dr. Poncer's analyses, and they're very well done. But I think what we were kind of hoping to see was if there were kind of sex differences within that that weren't being accounted for just looking at those age ranges specifically.
18:37
uh So we considered kind of sex within our models, we considered our body composition, which wasn't in the original model either. And so being able to kind of account for some of these things within a smaller subsample of the greater population. So the nice thing about his was he was able to utilize a lot of the sample, but for us, we kind of investigated a little bit more of a specific sample. So we liked that individuals from the United States and from Europe.
19:05
And we kind of made sure that there weren't too many outliers that could be influencing our data. So it was a little bit more kind of a specific look into it, but not to contradict what he said, but just to kind of ask a little bit more of a rigorous question of where does menopause fit into this and does it potentially change this? From our age ranges of reflective menopause, we don't think that menopause is as indicative of energy expenditure changes as aging is.
19:34
Oh, interesting. if you mentioned about body composition, and so you saw a shift in body composition which impacted energy expenditure, but it wasn't a sex difference per se, because regardless of sex, if that body composition changed, the energy expenditure would decrease. that correct? Yes. um So we did see, again, like women had a greater amount of fat gain, kind of percent.
20:02
body fat was higher within each of the age ranges, the young, middle-aged and older. And then the change between middle-aged and older women, they gained like a little bit more percent body fat than the men did. But overall, we saw kind of similar trends between those two, the two sexes. And so that, yeah, through what you said is just kind of how it could potentially be reflected within the energy expenditure and the similar changes.
20:32
Hannah, how does this fit with other studies that look at similar concepts, if you like? The SWAN study was one that I know a lot of people talk about, there's a shift in... The way that sometimes it's reported is that there's this doubling of fat mass when it comes to menopause, or there's a shift in energy expenditure. Is it as dramatic, like you mentioned about the fat gain, is it as dramatic as what sometimes it's...
21:01
it's characterized as or painted as? Yes. So there is definitely an increase in fat mass gain with menopause. And one of the big kind of questions and thing that has been shown within the SWAN study too, is that there's a little bit of a shifting of where fat is stored in the body.
21:24
So not only are you gaining more fat within your middle age time period potentially, but it's shifting from being stored more in like your hips and kind of gluteal region to more in the abdominal area. And that is one of the driving factors, I think, of the kind of consequences of menopause.
21:45
Women are more metabolically protected earlier in life with that type of fat storage in the hips and the glute region. And then as it starts to preferentially be stored around the midsection, you start to see kind of this increase in disease risk. And men will have fat gain as well with aging. This happens a little bit later for them, but theirs is also in that midsection area. So women will see kind of this like spike within midlife of risks of cardiovascular disease. And a lot of that's due to
22:15
just that accumulation of fat within that abdominal area that occurs. So even if they are not maybe gaining as much fat, it could just be this redistribution effect that's happening too. And this one study did show in an analysis about thousand or so women from that data set that the years preceding menopause, was that.
22:36
fat doubling and that increased two years into the postmenopause time period. And then after that, it leveled out. So that kind of rapid fat gain happened over those years. Hannah, it's interesting what you talk about with that fat distribution because it doesn't take a lot of additional fat in that visceral region to really impact on overall risk. Is that right?
23:02
Right, yes. So especially you have the two types of fat. have your subcutaneous fat, which is the ones that you can feel in your skin and pinch and feel. And then you have your visceral adipose tissue, which starts to surround the organs. And so that's the one that's more risky. And so when you have a lot of abdominal fat, you definitely will have more around your organs. And so that's kind of the indication that can occur with.
23:29
some of this dysregulation in your metabolism in terms of maybe glucose or insulin and some of the changes with your sex hormones that are happening at the same time leading to more of that cardiovascular disease risk. Yeah. Yeah. So even if it is a matter of several hundred grams, et cetera, increase or shift in that distribution, that actually has the potential to really impact on overall risk. And I think
23:58
Sometimes we assume it takes several kilograms of additional weight or something to really start impacting on actual risk, but actually it's quite minor when you put it in those numbers. Yes, definitely. I think the paper that we did with the W.L. Oldwater kind of reflects some of that of
24:23
Even though your energy expenditure may not be changing, your body composition is changing as you age. And so even if you are not expending too much in your midlife, you're expending around the same energy as when you were younger, your body composition's changing. And then as you age, you start to decrease your energy expenditure. So it's kind of a dumb-a-whammy in a way of like you're gaining more fat and then eventually you lose a little bit more of your energy expenditure.
24:53
So kind of working on optimizing health in the midlife is a big time period to be able to have healthy aging. Yeah, and this is sort of a side tangent actually, but I was thinking about this this morning was on my run. You know, I feel like for people who have gone through life relatively lean and slim by society standards have, you know, and I suppose
25:18
others might look at them and think, oh gosh, you're super lucky. You've never had to worry about what you eat or if you've exercised, it's never been from a weight perspective. It's always more than for enjoyment if you have. And I feel like because we place so much emphasis on how our appearance and our body weight, there's a whole subjection of people who are relatively slim looking, maybe, but these shifts are also happening within them and they may be.
25:47
even more at risk because their mind isn't geared towards thinking about health in that way. I don't know. Yes. There's uh been a kind of a newer subgroup that has been emerging in some research called uh normal weight oh obesity. And so it's individuals who are classified with normal weight or the BMI range, but based off of their body composition, they have a higher percent fat.
26:14
So that's kind of been an interesting realm of research that I think is becoming a little bit more interesting. And there's been a really big push within the clinical world to kind of move away from the BMI kind of more towards the body composition realm. So there's a big kind of push across the world to redefine what obesity.
26:38
is and now body composition is kind of being pushed within that of saying like, okay, if you have individuals with overweight or with obesity, getting them to do a body composition measure to try to assess like risk factors for how much fat do they really have compared to just the number of like, okay, you weigh this much versus your height. So it is, I think becoming more recognized as like a leading factor within uh the medical field and also in the sports world.
27:07
Yeah, nice. And I'm continuing on this tangent just quickly. You have an opinion on those BIA machines, because they're probably the most accessible ways for individuals. I'm not a huge fan actually of the at home ones. I'm sure they're improving, but as I understand, they're not that great. But what about the ones that people can access through their gyms or through their doctors? Are these a good way to understand better?
27:35
your body composition, your energy expenditure or your RMR or anything like that? I think they are a really great tool. So a lot of the ones that you mentioned that are in kind of more the clinical settings will be really great measurements. There's been a lot of validation that's gone on over the past years to kind of make their algorithms a little bit more accurate.
27:59
And the way that BIA works is through a bioelectrical impedance analysis. So there's a little bit of an electrical current that will run through your body. And so it can measure the resistance that it's feeling or has. So if you have more muscle, it will be a faster kind of current because of the water content. If there's more fat, it will be slower. So it does give a pretty good measurement, I would say, of
28:24
the accuracy is not as great as maybe the Dex would be, but it's a really good proxy that can be occur in those settings. And there's a paper by uh Dr. Grant Tinsley, who he measured some of the at-home scales, found that most of them were not that great. They did not hold up against a good four-compartment model or the Dex model.
28:50
But I think like the at home ones, if you are measuring consistently on them, they could be a good way to kind of track some progress if you have certain goals, even if it's not 100 % accurate compared to what a BIA at your doctor's office or a DEXA scan would be. So as long as you kind of take the new, you're looking at, I think they can still be helpful to track certain changes over time. But yeah, most gyms now I do think will.
29:17
The handheld ones that you just hold with your hands are going to be less accurate than ones that you can use for your feet and for your hands. Those will be probably the better ones to go for. ah But yes, both of the VIAs can be helpful to estimate that body I remember when I started uh when I used to do in-person clinics, I had one of those Omron hand machines.
29:44
I loved it because I was, this is extra data, but I mean, was not that accurate, but fun to have, fun to have. Sometimes helpful to have a place to start and just to kind of assess what you're looking at. And if you're seeing changes, then the changes probably are being reflective of what you're noticing. Maybe not as big of a magnitude or maybe smaller, but they can still be helpful for tracking over time. Yeah. Hey, Hannah. So when we talk about
30:12
the total daily energy expenditure declining with age. What are the numbers and what do they reflect in terms of our day-to-day behavior? Is it equivalent to a meal? Is it a snack? it someone doing 10 minutes less walking? How do we quantify them in a way that puts some meaning, I suppose, behind it? Yeah, that's a really great question.
30:43
As we age, there's certain things that happen. So when we look at contributions to energy, like I mentioned, we have sleeping energy expenditure, you'll have thermic effective food, you have kind of the arousal or just like when you're awake throughout the day. So some of those components will change over time with age. So you might start to sleep a little bit less. You might start to see some changes in your diet if you're not eating as much.
31:09
And then the physical activity you mentioned is another big one. So oftentimes we become more sedentary as we age. So total daily energy expenditure is probably reflective of a lot of those things. Like you're losing fat mass, you're getting older, you're not exercising as much. So in terms of the contribution of kind of how to look at it over time, I would say that the physical activity one is like one of the easiest ways that you can intervene in your energy expenditure and try to keep that.
31:39
um as optimal as possible. So continuing to try to reach the 150 minutes of moderate physical activity per week or 75 minutes of vigorous activity. And then as we age, resistance training becomes even more important because that's how you can maintain your lean mass. And it's also very helpful for functionality, which is another risk factor. If your muscles are becoming weaker or smaller, you may have an increase for decrease in
32:07
functional living, your daily living, um increased risk of falls. So yes, resistance training is a big one. And then balance training is another recommendation for aging. So at least like once per week, trying to work on balance, things like standing up from a chair without using any assistance, doing kind of heel to toe walks. Those are some easy ways to practice your balance that can help with the muscle coordination and also decrease risk for falls.
32:37
So as we age, definitely will see this decrease just naturally in our energy expenditure. Not all of it we can recover, but focusing on increasing your lean mass or at least maintaining it, maintaining or improving your physical activity are two key variables to look at. And Hanna, you obviously reproductive status wasn't confirmed in the data set, but you used the age groups, 30 to 39, I think, 50 to 54.
33:06
55 to 70 as proxies for those stages of menopause. So do you think that that sort of mid age, that perimenopause time, was that when you saw the major shift in body composition? And do you think that this is like a critical period for women's metabolic health?
33:27
Yes. So within like the 40 to 54 age range within our study, we did see that there was this increase in percent body fat. So it went from 37 % in our younger age group to 40 % within the middle age group. And then it went up to 43 % in the older age group. So we kind of saw this like a progressive increase over time. But you know, that kind of initial jump.
33:55
is an area of time that you may be able to intervene a little bit easier because we're not seeing that decrease as much of the energy expenditure time period. So if you can work on optimizing, again, maintaining your lean mass, exercising, have some dietary interventions that could be helpful for maintaining health overall, that could be a great time period to you.
34:19
help with the healthier aging if you do see those decreases in your energy expenditure around age 60 or so. So it's a great way to kind of be preemptive and focus on healthy aging in that midlife period. A lot of women within this time period will experience vasomotor symptoms. They'll be experiencing other symptoms of menopause that just are not the easiest to go through and not the easiest to cope with.
34:48
It is a time period to pay attention to and to try to help with optimizing health the best you can. And then as you transition into postmenopause and maybe recover from some of those symptoms, you will have like a very strong kind of baseline there. Yeah, nice one. Did you say body fat percentage was 38 % jumped to 47 % and then went to- no. 37%.
35:14
to 40 % to 43%. Okay, okay, there you go. Is it high, Hannah, as an average? So women will have a little bit higher, but I think in this sample, it was a little bit higher than probably more of like a leaner, like athletic population would be. So I think, man, I don't remember exactly off the top of my head, but maybe around like,
35:40
25 to 30 % in a younger age group is a good range to be in. So this was a little bit higher than that. But yes, overall, it is a little bit higher of a body percentage. But I think the 40 % and 43 % are more similar to what we've seen with the SWAN data set, for example, that women will gain that percent body fat. Yeah. And it's interesting, isn't it, when you think about it? Because I think a lot of people have
36:09
perception of what a healthy body fat percentage is. And I don't know in your work Hannah, but I hear it a lot with women. They're like, oh, I'm 19 % body fat and I want to lose body fat. I'm like, People have a sense of what they perceive to be lean is actually incredibly athletic versus what a healthy body fat percentage is. Albeit though,
36:36
um At the numbers that you're describing, that's probably no surprise given that in your data set of the US women and European women, like 70 % of people globally or in Western populations are carrying excess body fat or are categorized with obesity. It's probably no surprise really. Right, exactly. And I think in the study from what I remember, um
37:04
most of the individuals had overweight. that was kind of the mean average within our groups were individuals with overweight. So that does make sense to have a little bit higher percent body fat. These were not individuals with normal weight or with obesity, kind of that range, but the mean that was within that overweight category. Yeah, nice one. Hannah, you mentioned that once
37:29
You sort of accounted for body composition that males and females, they don't necessarily, there are no um sex differences per se, but that males actually decline a little bit slower in terms of their TDEE compared to, like across all age groups, whereas women sort of stayed relatively stable until that sort of older age group.
37:54
Right. Yeah. So in the men, we did see like a little bit more of a decrease between the younger and the middle aged and then the old where it was like a little bit more comparable for women with between the middle aged and younger. ah But we select those are some kind of hard, I think, to kind of interpret data just because, um you know, it was a little bit different, I think, than what we had hypothesized.
38:24
But I think what we kind of see is that there could be these just physiological differences em that are happening in either in the body composition or just outside of em the way that energy expenditure is being expended. it's physical activity, like I said, or changes in diet that are happening, we couldn't really account for a lot of those aspects within this data set. So men may have been like
38:50
decrease in their physical activity within that middle age where women, we know that actually a lot of women will try to kind of combat that gain in fat by exercising more. So there's potential that the confounding factors that we weren't able to have the data for in this analysis. Yeah, no, that makes perfect sense because of course, if we're looking at overall energy expenditure, we can't determine changes in
39:17
of that cellular level versus changes in behavior or changes in hormones or whatever that might be leading to the overall sort of pattern. Yeah. I saw in fact there was a narrative review was published maybe just a few weeks ago, Hannah, that suggested, the overall, obviously a narrative review is someone's opinion rather than, you know, sort of what the data says and the authors
39:47
sort of took the data and hypothesized that there is a shift in resting metabolic rate in menopause or perimenopause, but they were more based on, as I understand it, sort of preclinical trials and mechanistic trials rather than sort of human data set. uh Is that what we understand to be true for, or what you understand to be true for resting metabolic rate? Like we just don't think that there are, there's not enough research
40:15
in humans to determine that there is in fact a shift in that resting metabolic rate? I think that is a very fair assumption because the data that are in more animal or cell studies, I think, does kind of show and highlight the importance of estrogen within energy expenditure.
40:36
And so you can kind of maybe try to like extrapolate that to humans and say like, well, if you're losing estrogen, then you're probably losing your energy expenditure with that. But I think as we kind of talked about throughout this podcast, there are just so many other factors that in humans can contribute to energy expenditure, resting energy expenditure that are not just driven by only estrogen. So I think that your kind of summary of it was a really
41:05
reflective of my opinions as well that we do need a little bit more in-depth studies if we want to look at doubly labeled water, for example, or metabolic chambers, how we can kind of see these assessments over time. uh Those would be like some important questions to like ask overall. Yeah, nice one. And as I understand from your paper, when you saw that the drop in resting energy expenditure was in the realm of about
41:34
roughly 100 calories or something per day. it wasn't like, what is that, like an apple or something a day? Right, exactly. So we did, there was a longitudinal study that was completed here at Pennington that looked at women across time. So they looked at women who were premenopausal and then followed them for 10 years.
42:04
and we did chamber studies with them. And I have the data right here actually. So individuals who went into menopause lost about like a hundred calories. I don't even think it was quite that much, like I have these mean differences. And then premenopausal women also had a decrease in calories by about 50. um Oh, here it is. So a nine point.
42:30
3 % change in postmenopausal women for energy expenditure and then a 7 % change in premenopausal women over the same time period. So I think that that kind of also kind of shows that we just see decreases in time. It could be leading to these energy changes. We saw that there was a decrease in spontaneous physical activity in the postmenopausal women by about 30%.
42:57
and then a decrease in spontaneous physical activity in the premenopausal women by 38.7%. So I do see that there could be like that contribution of physical activity being a driving factor in energy expenditure and what we can see the changes occurring too and how kind of important that is within our lifestyles. Yeah, nice one, Henna. So what's next for the research for you then?
43:27
uh taking some of the results of this paper and analyzing further or is it the basis of clinical trials? So what can we expect? Yes, so I have an analysis actually of that longitudinal data set I was just speaking about. We call that the Healthy Transition Studies at Pennington by Dr. Jennifer Lovejoy.
43:52
And I have completed an analysis of that looking across time. And we were really interested in looking at skeletal muscle mass because of its potential role in energy expenditure and health and how that changes across the time periods. And we have a analysis that includes our physical activity, some of the dietary changes. So kind of taking some of those limitations that I've mentioned in this study.
44:21
to try to see like if you follow women across time, what is changing? How is it changing? How is that affecting body composition? So that manuscript is in review right now. So let's see if that gets published soon, hopefully it will. And then some future kind of studies I'm looking at is actually being able to utilize our chambers here at Pennington to look at uh energy expenditure and how diet can kind of influence the way that you are utilizing
44:49
macronutrients and expending energy and if that can change between women who are experiencing menopause symptoms versus those who are not. So some other questions came up I think within this data set. We do see maybe similar trends between men and women, but when we look at women specifically there's these kind of questions with we have estrogen, we have symptoms, we have lots of changes that are
45:15
happening physiologically just outside of body composition and how are those influencing energy expenditure? Yeah, I think these are such important questions, Hannah, because there uh are a lot of questions being raised and a lot of people are quite adamant that there are no differences between the sexes, which by all accounts, you also like this, that it's not like this paper.
45:42
showed that there were huge scale differences related to hormones or anything like that. because of those shifts in hormones and what occurs in the life cycle for women, it just feels like we cannot say that the science is settled here. So it's so great that you're looking further into what might be going on. Right. And I agree. And I think that going back to our conversation, we do know that estrogen has that role in
46:11
uh lots of different body systems outside of reproductive function in women. And so when you lose estrogen, what are some of those effects that occur across the body systems? And then I'm interested also in how some of these modifiable factors of aging that we call them like secondary measures such as your diet and your physical activity levels, uh some of the social factors, how are those really influencing aging, especially
46:40
as women uh experience menopause within their midlife and go through their vasomotor symptoms is a really big one. That's a challenge. Other challenges that men don't experience in the same way. So even if the end result is a decrease in allergy expenditure at age 60, women still experience a lot of different social and physiological changes that happen. Yeah.
47:06
Well, Hannah, these are really important questions and I'm really pleased that I got this opportunity to chat to you about them and really excited to see just this emerge. It's not really emerging, it? But it just does appear to be this increase in research in and around this area. So you must feel super stoked to be sort of, you know, part of the part of that picture as well. So good luck with all the rest of your research.
47:35
Thank you so much. I appreciate being able to come and talk about it. And I'm looking forward to the next steps and hopefully contributing more of that human research to our questions and being able to see how we can optimize healthy aging. Nice one. Thanks so much, Thank you.
48:04
Alrighty, hopefully you enjoyed that as much as I enjoyed chatting to Hannah. And as I said in the intro, it's just so great to see more evidence or more research come out in the space of uh perimenopause, menopausal women, where there are distinct physiological changes that occur that could potentially shift things that we may not currently know about in the research. hopefully you enjoyed that. And as I also relayed,
48:33
I've got a link to Hannah's university page in the show notes. So that's it from me today guys. Next week I chat to my mate Grant. Cannot wait to share that interview with you. Until then though, you can catch me over on Instagram X and threads @mikkiwilliden, Facebook @mikkiwillidennutrition or head to my website, MikiWilliden.com and scroll right down to the bottom, pop your name in the box to jump on my email list and be the first to hear
49:03
with the next Monday's Matter Plan, which is due out the Accelerator program early to mid-July. So yeah, find out more about that there. All right guys, you have the best week. See you later.