Is your gut the secret to anti-aging? 6 science-backed ways to boost your bone strength, muscle, and balance | Prof Elaine Dennison

Bones as living tissue

0:00Welcome to Zoe, Science and Nutrition, where world-leading scientists explain how their research can improve your health. It might surprise you, but your skeleton isn't just a rigid frame. It's one of the busiest organs in your body. Bone is actually a living tissue that constantly rebuilds itself, communicates with other organs, and plays a vital role in immune health. It might not be as sexy as muscles, but bones are just as important. And whatever your age, there

0:34are things you can start doing today to help ensure that your bones support you for the long haul. Joining me today is Professor Elaine Denison, rheumatologist and professor of musculoskeletal epidemiology at the University of Southampton. She's a world-leading expert in bone health, why it goes wrong, and how to protect it. Her research explores how our bones change throughout life, and how best to protect our skeleton from childhood to old age. This episode isn't just about avoiding broken bones. It's about discovering one of the most remarkable and most

1:06overlooked living tissues in the human body. By the end of this episode, you'll think completely differently about your skeleton. You'll know exactly how to protect your bones so they can look after you. Elaine, is bone health only something that older women should worry about? No. Are my bones a non-living scaffolding, a bit like my fingernails, whose only job is to stop my body from collapsing into jelly? No. Can I tell that my bone health is declining

1:38without getting a scan? No, not normally. Do stronger muscles make stronger bones? Yes. To maintain good bone health, do you need to take expensive supplements? No. And finally, what's the biggest mistake that most people make about bone health? The one thing that I think is most important is not leaving things until later in life when you've got a problem, because protection is always easier than cure, isn't it?

How bones rebuild themselves

2:06You know, one of the things I'm struck by is on social media, there's an enormous amount of focus on building muscle, but you very rarely hear anything about bones. I was so confident that bones are just like my fingernails or my teeth, like really hard, but basically dead, and that they were just sort of there, you know, they're like a coat hanger, you know, the stuff hangs off it. Otherwise, I would end up sort of like a puddle, like a slug. But what I'm hearing from you is I've got this all wrong? Bones do play an important protective role. So they do help protect internal

2:40organs, but they're definitely not a dead tissue. They're very much a living tissue. As we're sitting here, our bones are being constantly turned over. So bone is being broken down, bone is being formed. And in health, obviously, that's a balanced process. So the amount of bone that you break down, you replace. And it's a way of kind of the body's DIY. If you think of if you've got a crack in a wall, you might want to put some polyfiller in to repair that. So your bones effectively should be doing the

3:12same thing. Where we get into problems is where that becomes unbalanced. So more bone is broken down than is formed. And then obviously you lose bone. So that is a problem. Beyond that, bones do more than just protect organs. You know, you've got cells, you've got bone marrow that's being active throughout your life. So you're making cells in your bones as well. It's a very, very active organ, but it's definitely a living thing. So there's absolutely a need to look after it. So I'm fascinated by this

3:45idea that I'm both breaking down my bones and rebuilding them. Yeah. I can see why it would make sense to rebuild them if they're broken. But why on earth would my body be like breaking down my bones? That seems really stupid. What would normally happen is that in a bone, you might get a tiny, tiny little crack or irregularity on the surface of the bone, like a microfracture. And what your body can do is work out where the bones need either repairing or strengthening. So to do that, what it does

4:18is it sends some little cells in called osteoclasts that will make the area ready for repair. And then osteoblasts will come in and do the repair. So it should be a balance cycle where everything results in a sort of a net equal balance. But it is important because if you completely stop bone turnover, and we've got drugs that would do that, then you can see little fractures appearing actually enlarged. So you can see that actually, it's a very beneficial process to have bone turning over in this way.

4:52So I think what you're saying is, just through normal wear and tear, I'm getting like tiny little fractures in my bone, just from like, presumably walking around and falling over and whatever I might do. And then my body is identifying that. Is that the osteoclasts that you said? There are other cells in the body that are sort of detecting what's going on as well. But what will happen is the osteoclasts will come in, they'll break down a little bit of bone, prepare the area, and then the osteoblasts will come in and fill in that gap.

5:22And when you say prepare the area, it sounds like my body identifies that there's this tiny little crack. And basically, it breaks it down. Like, it's almost like there's a, I'm thinking now, you know, there's a broken part of the wall. It's like ripping out some of those bricks. And then I'm going to hopefully put in some new bricks afterwards. Yes. And so that means it's not just like they're coming in and building. Actually, I'm having this part of my bone sort of pulled away. And then something you put on top. So it's already massively dynamic compared to anything that I would have thought about, which as I think about it,

5:55it's sort of obvious because I've seen my children grow up and clearly their bones, I guess, are getting longer because I've never noticed them just like falling out and new ones coming in. But I guess I had sort of assumed that when you're an adult, that was done. But this isn't true. This like repair and replacement is something that continues throughout adult life. Yes. Repair and replacement continues throughout adult life. Obviously, it's a little bit different in children and young adults to when you've reached what we call skeletal maturity. So up to the age of about 30, then you're not only sort of balanced in terms of bone, you're actually

6:32growing bone, you're actually increasing bone mass. So when you talk about your children growing, obviously their skeleton gets larger and then that skeleton gets stronger. So up to the age of 30, you've actually got this window when you're really building your skeleton. So it's a really, really important part of your life. That's really interesting. So you're saying that when you're fully grown and I'm thinking about, you know, my kids, that's often sometime between like 15 and 18, I would have thought them as being done because they're not

7:04getting any taller, but you're actually saying their bones are continuing to get stronger, which presumably also means heavier from that point.

Peak bone mass and menopause

7:12Yeah. So what we'd normally say is that you can, you can actually strengthen the skeleton up to the age of about 30. So up to the age of about 30, you're on a trajectory to something that we call peak bone mass. So that is the maximum amount of bone that you're ever going to have in your life. So the amount of bone that you can get by that point is really helpful. You peak at about 30 and then if you're lucky, you sort of, you stay along on the level for a while. But then sadly, in most people, there will be a decline and it's particularly marked in women

7:48because as they go through menopause and they lose estrogen, then that is a catalyst or is normally a catalyst for sort of quite rapid bone loss. Why would your bones change as you go through menopause? So estrogen is a really, really important hormone for bone health. I mean, it's important in men and in women, but you need to have enough estrogen on board really for bone health where it's very, very helpful. For women, obviously, most of that comes from sort of reproductive organs. So as they

8:20go through the menopause, they lose that benefit. You do still get some estrogen manufacturing in fat tissue and adipose tissue. So there is a little bit of protection from there, but that loss of estrogen is quite a big hit for the bone because you get faster bone breakdown than bone formation. Everything becomes unbalanced, basically. Could you help us understand why this change in estrogen is then changing my bone health?

8:52Because it's affecting the balance. So what you would normally have in health is a balance between bone formation and bone breakdown, and you get an altered balance. So you get increased bone breakdown relative to bone formation. You've got two types of cells. You've got osteoblasts and osteoclasts. And the osteoclasts are the cells that come along and take a bite out of the bone, and the osteoblasts are the ones that come in and fill in the hole. That's what would happen. Commonly, osteoporosis happens when, as I would say, the osteoclasts get greedy and the osteoblasts

9:28get lazy. So you get that imbalance, and that's when you start to lose bone. And lots and lots of things can affect that balance. So lots of things can make that happen. But one of those things is estrogen withdrawal. So that's why for women, the menopause is a particularly significant time, and that's when a lot of women start to see problems with bone loss. And is it only women after menopause who have this shift where the bone breakdown is getting

10:01higher than the bone creation? No, I mean, men do suffer a little bit. I mean, osteoporosis is particularly common in women. But with men, you will see bone loss as well.

Osteoporosis and fracture risks

10:13And Elaine, what is osteoporosis? Osteoporosis is a loss of bone that makes you particularly vulnerable to fracture. So osteoporosis is a term that we use for lower than average bone density. But it's an asymptomatic condition. You wouldn't know unless you go on to actually break a bone. So it's the impact of having thin bones. So you've talked about the risks for women after they go through menopause. Are there anybody else who should be worrying about this sort of increased risk of weaker bones?

10:47Yeah. I mean, it's not just women. All older people are at risk. So we do see osteoporosis in older men as well. There are groups of younger adults that we see osteoporosis in as well. So people who have to take steroid tablets for any reason, then they're at risk of osteoporosis. And normally their physician would be monitoring them. If someone has a history of anorexia, then often that has impacted their bone health. So they haven't reached their optimal peak bone mass

11:22or their potential. And then they tend to lose bone after that as well. People who have got gastrointestinal problems, so someone's got inflammatory bowel disease or celiac disease or something like that. There's quite a long list of things that a doctor would look at and it should trigger something that says, oh, I might need to investigate this. So someone's listening to this and saying, sure, that's sort of interesting if you're a scientist and you're curious around like exactly what might be happening to bones, but why should I care about

11:57the fact that I had peak bone health when I was 30 and now I've got less good bone health? Why does it matter? When I hit 40, I started feeling tired and sluggish. I remember thinking, great, this is it. It's all downhill from here. But I was completely wrong. It wasn't my age, it was my diet. It was literally sapping my energy. I was trying to juggle kids, work and exercise. And back then I just grabbed whatever food was nearby. I still have that crazy schedule, but what's changed is what I put in my

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13:27It matters because of the risk of fracture. So there's not a perfect correlation. Your bone density does not perfectly predict whether you'll have a broken bone or not, but there's a very strong relationship. So if you have thin bones, if you have osteoporosis, you are more likely to break something. And there are many, many different types of osteoporotic fractures, but a lot of people will know someone who's broken their hip or their wrist or a bone in their spine. As your bones get

14:02thinner, the chances of it happening go up. So that's why we'd encourage people to try and think about how they can protect their bones because no one wants to have one of those fractures. And Elaine, could you talk through what the implications are of those fractures? Yeah. So the implications are different for different fractures. So if you break your wrist, it's going to be painful. It's probably going to have an impact on you short term, but you should recover. If you break a bone in your spine, if you have a vertebral fracture, there are quite a few

14:39studies that suggest you are more likely to die than someone who has not. But that may be in part because you have other underlying medical conditions that caused you to break that bone in the first place or that contributed to it. And that's what we're really seeing. The hip fracture can be a devastating event for people. There is a very significant risk of dying after a hip fracture, and that's quite early. So that's in the first sort of six months. So that can be typically more

15:14associated with direct complications of the fracture. So someone might develop pneumonia, they might develop a blood clot. There are other sort of immediate risks of having that fracture. And it is obviously a really nasty fracture to have. It's very painful. And then obviously you have to have surgery, quite significant surgery. And then you need to get up and about again. It's broadly a rule of thirds. So if you have a hip fracture, a third of people certainly will die. A third of people will

15:46recover to some extent, but not necessarily to the level that they were before. And then a third of people will be able to return to previous levels of function. So that paints obviously a pretty devastating picture. I have two questions. Firstly, I'm interested because you talked about thinning of the bones. Could you help us understand a bit more, what does that actually mean? Does that mean literally that if I looked at the bone, it was, you know, it used to be five centimeters wide, two inches, and now it's half. And then why these very,

16:17you know, they're very specific injuries you're talking about. Why is that? Yeah. So if I start with what happens to bone with age. So, I mean, the best comparison is if people know crunchy bars, crunchy chocolate bars, if you were to cut a crunchy bar across the middle, or if you just bite into it, you've got the sort of the chocolate shell around the outside, and then you've got the kind of the honeycombe-y bit in the middle. That honeycombe-y bit has got

16:48struts, you know, it's not a solid structure, is it? It's sort of almost like a lattice. So what happens in osteoporosis, if you look at it under the microscope, what you'd see is that those slats, that lattice just looks a little bit sort of ragged, a bit tatty. So some of the lattice is broken down. Some of it looks a bit narrower than it should do. It just looks like it's gone through the walls a little bit, and that structure isn't as strong. So the outer chocolate

17:19shell, if you like, would also be affected, but it's that lattice that we particularly see quite dramatic changes in. That's the trabecular bone. So that's what's happening as I'm losing bone density, or to use your word, osteoporosis is a way of saying that I've lost this lattice. I've got less bone and less good structure in there. How does this tie into those very specific... Because I've got quite a lot of bones, haven't I? You have. And I picked those three because those are the three that researchers used to focus on. So

17:53we don't include the skull in that, but obviously you can break pretty much any bone through osteoporosis. It's just we don't have such good research in that because people are focused on those three. But we do know that if you count up some of those other fractures, that's a huge number and it's got a huge impact in terms of healthcare systems. I feel like I don't know any young person who has broken their hip, but I know more young people

18:25probably who hurt, like break things probably than older people. So how does that happen when you're older, but it doesn't seem like it happens when you're younger? Yeah. Well, if you're young and you've broken something, it's probably because of trauma. So something's happened. You've had a car accident or you've come off a motorbike or you've fallen off something. As you get older, you need much, much less trauma to break something. So we talk about fragility fractures, fractures that occur from a fall of standing height or less. Some fractures just

18:57happen spontaneously, but normally it'd be a simple trip or a simple fall. And that would be enough in certain circumstances to lead to a fracture. And so if you have good bone health and you trip over from standing height, you don't expect to break the bone? That's the thing. You'll bounce, we say. I mean, you don't really bounce, do you? But yeah, you don't break anything. Is there anything also about like balance and reaction? Definitely. Speed fitting in here? Yeah. So if you can stop people falling over, then that's going to protect a significant number

19:30of people. The other thing I'd say is that if you look at the pattern of the sorts of fractures that people have over their life course, they tend to change a little bit. So it's more common to have a broken wrist in your 50s or 60s. Because if you fall, you tend to put your hand out to protect yourself. You tend to go forwards, do that instinctively. And you might break your wrist, but you tend to protect other things. As you get old, you seem to lose that protective reflex.

20:02So then you're much more likely to fall directly onto the hip. And at that point, you increase the risk of a hip fracture. If this episode has changed how you think about your bones, please share it. Most people don't think about bone health until it's too late and something breaks. You might change their life.

20:23We've talked a lot now about bones as breaking. And in a way, I feel like I'm in my comfortable world of my bones being effectively sort of dead, even if they've been built or not. But I know if I come back to the quickfire questions, you were saying that they do a lot and their role is not only as this sort of important scaffolding. How else are our bones contributing to our health?

Bone marrow and the immune system

20:45Within your bones, you have bone marrow, which is a factory for blood cells and things like that. They're also involved in sort of what I'd call body homeostasis. So the maintenance of levels of hormones and level of essential vitamins and minerals and things like that. So there are reservoirs for a lot of things. There is sort of a storage area for a lot of things that you will need. Can you give me an example? Yeah. So if you think of it, I mean, calcium is the classic one, isn't it? So, you know,

21:17the calcium, your calcium is stored pretty much in your bones. So you've got hormones that are released centrally that determine the right levels of these things in your blood. So my body is basically pulling calcium out of my bones to put it into my blood. Can do. I thought my calcium was only for my bones, but are you saying that other parts of my body need calcium as well? Yeah, you need calcium. Yes. You need it for many, many, many regulatory things. Yeah. So the bones are also like this reservoir of nutrients, but you also said something about

21:48the immune system. Yeah. So you've got a lot of immune cells sitting in the bone marrow. So what we know is that you need obviously a healthy immune system. You don't want your body to be in a state of chronic inflammation. So your body has to be ready to fight, but not constantly activated. I mean, you asked earlier about stress. You said, you know, is stress a bad thing? Well, stress might be a bad thing for your bones as well as for everything else, because it leads to your body

22:24just being sort of constantly on a state of edge of alert. And long-term that can be harmful for many things, including probably for your bones. Can you help me to understand this bone marrow thing? Like I know that sometimes you don't see it very often, but you might get served like some meat that has the bone marrow in. Beyond that, I have absolutely no idea what it's for or why I care. You need certain cells in your blood for sort of basic functions to transfer oxygen,

22:54to fight infections, to do things like that. So the bone marrow is where those cells are made. It's like a factory. What has actually been made in the bone marrow? All the blood cells, white blood cells, red blood cells, many, many different subtypes of that. But their role is to carry oxygen, to fight infection, to remember when you've been exposed to infection before so that you can mount another immune response, to control inflammation. There are loads and loads and loads of cells.

23:25And all of these are made in my bones? In the bone marrow. The bone marrow is a really important part of that. So one of the things that I've learned from hundreds of these podcasts now is that good gut health seems to be linked to like a remarkable number of different areas. But still, I was absolutely shocked to hear that there's a discussion about a gut-bone axis. What is that?

The gut bone axis

23:50Yeah. So, I mean, gut and bone are very closely linked. If someone's got gut pathology, if they've got problems with their gut, then that is a strong risk factor for osteoporosis for thin bones because they can't absorb what they need to. So a lot of the things that we've been talking about that are important for maintaining healthy bones are absorbed through the gut. So obviously, you need good levels of that. Beyond that, obviously, you've got a lot of bacteria in your gut. So those are important

24:22because they will help convert fibre to sort of short-chain fatty acids. And that's important for inflammation. So we know that if you've got chronic low-level inflammation, that's a bad thing. So that will tend to lead to poorer bone health. So the gut microbiome is important for maintaining good bone health. That's fascinating. So you're saying that if I have this low-grade inflammation,

24:54which comes up so often on these podcasts as something that's bad for us, this is actually in some way disrupting that pattern of like eroding away my bone and rebuilding it that I would have? You've got an imbalance, yeah. What tends to happen as a result of inflammation? So you tend to have more bone breakdown than bone formation. So you get that imbalance that we've been talking about. One of the things that I hear elsewhere around inflammation is that it's something that our body evolved for, for like a good reason. Like I'm running away from a lion and I need to do something. So do we have any understanding why inflammation would have any

25:28impact on this bone mechanism, which sounds from listening to it, so it's sort of slower than pumping the cortisol into my bloodstream. It's kind of a different thing. So if you're facing a lion or something like that, you absolutely need that acute response. You need that acute flight or fight response. So your cortisol levels will peak then. What you see in chronic inflammation is chronic low levels of slightly elevated cortisol. And cortisol is one of the hormones that's bad

26:02for bones. So that's what you're seeing. So raised level of this cortisol. Yeah, just a little bit, you know, not of the level that's really, really high. But yes, chronic low level is bad. Why is it that when your cortisol rates go up, do we know why that would lead our body to start to sort of strip away at the bones faster than otherwise? Cortisol has a huge number of effects and you want it in a sort of quite a tightly regulated

26:33level. If you have some profiles of a high level of a hormone, that can be a good thing. But if you've got chronically elevated levels, that's bad. So in osteoporosis treatment, if someone has osteoporosis, you might give them injections of PTH, teriparatide. So there are some injections that you can give where you're giving a spike of that drug and that actually helps you build bones. It could be a really useful drug in treating osteoporosis. But if someone has got naturally high levels of the same

27:09hormone that are a little bit lower than those spikes, but carry on all the time, that's bad for bone. So the way that a hormone is delivered, served to the body matters. It's a miracle more doesn't go wrong, really, to be honest. It's very, very tightly regulated. It definitely sounds... I'm getting this picture of something very complicated where I've got this immense team of builders running around my body, breaking down all the bits that are damaged. And then somebody's got to come around the next day and fill it all. And potentially,

27:41I have a situation where I've got more of these builders tearing down my bone than coming around to fix it. And so I can see that over time, it's getting worse and worse. I also get an appreciation of just how important these bones are. So I'd love to discuss a bit more what else might be harming my bone health. And so you've talked about menopause, but are there any everyday habits, for example, that could be weakening our bones without us knowing?

Everyday habits affecting bones

28:09Yep. Smoking is bad for bones, definitely. Too much alcohol is bad for bones. Too much alcohol is bad for bones. Yes. Some alcohol is good for bones, interestingly. So alcohol has a very interesting relationship with bone health. So what you normally see is that the group of individuals who drink some alcohol, but well within recommended levels, have got better bone health than people who don't drink any alcohol at all, and definitely better than people drinking too much. So moderation is key.

28:45You're the first doctor I've managed to get on the show to tell me that drinking a little bit is good for me. Drinking a little bit is good. That's the good news. The other bit of good news, which goes contrary to most things, is that actually carrying a little bit of weight is good for bone as well. Well, Elaine, we have to get you on the podcast more often. So not only should I be drinking, but if only I could get put on a bit more weight, that would be better. It's also good. Why is putting on more weight better for my bone health? Three reasons, actually. Firstly, if you do fall, you've probably got a bit of padding. I'm

29:15particularly thinking of your hips. Secondly, because estrogen is made in adipose tissue. And finally, if you've got a bit of weight, that's a bit more loading through the skeleton. What about caffeine? Having a huge amount of caffeine could be detrimental to your bones because it might affect the calcium balance. But in general, having a couple of coffees a day is probably okay. To be honest, you're probably better off drinking tea because there's been quite a lot of research saying that some tea drinking might actually be beneficial for bone. But

29:49if you're going to drink coffee, then you don't want to be having lots and lots and lots. Is it the caffeine in the coffee that's causing the problem? Probably. Now, you also talked about the psychological stress impacting bone health. Why is stress a risk factor? Again, probably because you've got that sort of that chronically raised cortisol level. You're probably also not sleeping so well if you're stressed. And there's some suggestion that actually that might affect your bone health. And then finally, because if you're very stressed,

30:23you're probably not doing the other lifestyle things that are helpful. Not eating what you might otherwise do. You might not be doing the other things that you might normally do. I also heard you talk about steroids earlier as something that could be harmful for my bone health. Are there any other sort of common medications where I could have a side effect on my bone health? There are lots of drugs that can do. Some of them are stronger than others. I guess the topical one

30:57are the DLP one drugs. That's an emerging area that's quite important. People have obviously benefited a lot from the medications if used in the right way with the right support. But you lose not just fat, but you also lose muscle. And muscle is very important for bone. So there's a lot of research at the moment trying to understand whether there might be a long-term impact on fracture risk. And the

31:28reason we say that is because if you think of other parallels, you know, people have had surgery, you know, gastric banding or, you know, partial gastrectomy, things like that. Their fracture risk, their risk of breaking, something typically goes up. So there's a lot of effort at the moment going into understanding whether we're going to see the same pattern with some of those drugs. Can you help us to understand that? Because at the moment, I'm not understanding the link between losing muscle and why that's having any impact on my bones.

31:58Because the muscles are really important for bones. So they sort of, again, there's a lot of cross-talk between muscles and bones. And bones are strengthened by having enough muscle around them. So what you would normally do is link muscle and bone health. And if you lose muscle, then that will almost certainly have an impact on your bones as well. Even if it wasn't having a direct effect on bone density, and there probably is some kind of relationship, then if you've lost a lot

32:35of muscle, that increases fall's risk and things like that. So you're more vulnerable from that. I think it's another story about how you have to be very careful that when you're losing weight, that you're maintaining muscle.

Exercise and bone strength

32:49Yeah.

Exercise and bone strength

32:50We've talked a lot about these actions that are maybe increasing the rate at which the bone is being pulled apart. But is there anything you can do to actually increase the pace at which the bone is getting rebuilt? And do these muscles fit in in any way? Exercise. A resistance exercise is very powerful. There's a lot of muscle-bone cross-talk, where a muscle will pull on a bone that will typically strengthen the bone. It will be different

33:19at different ages. But in general, if you've got good muscle mass, you will have better bone health as well because of the sort of that cross-talk. The analogy I'm thinking about is like with going to the gym, you have to sort of hurt your muscles to make them then go stronger. And you're saying this is almost the analogy on my bones, that the muscles are pulling on the bone. And the bone is like, wow, I'm getting yanked really hard by these muscles. I need to make my bones stronger. I need to make it a bit stronger. Yeah.

33:49And so does that mean that if I sit on the sofa all day long, my bones will weaken? It's a bad thing. They won't try and rebuild them? Yeah. You need to be doing things. Actually, that's really interesting. Now, before we move on to all the ways you can build healthier and better bones, I'd just like to ask, how can someone listening to this know if their bone health is declining? There's no way that you'd know unless you have a DEXA scan. If you've broken something,

34:20if you've already had a fracture, then in most healthcare settings, someone would have picked up on that and would have said, oh, we need to consider this. Let's start doing some tests to see whether you're vulnerable to another fracture. Now, that is a little bit more nuanced than I've just told you because there are computer tools that you can use through answering a load of questions that give you a good steer into whether you're likely to

34:54be at risk. So if someone went to a healthcare professional and said, I'm worried about my bones, they may well start by asking some of those questions because that gives a good idea of someone's risk. Frax is the one that we often use, F-R-A-X. You know, you can just Google Frax and it'll come up and ask you a load of questions. And if you've got your bone density results, then you can put that in, but it will give you a number. And that is probably the way that

35:30a lot of people are trying to manage demand on the service as best they can.

Checking bone health and medications

35:36So I'd love to start talking about what you can do. And actually, I think this feels like the first place to start with. So if you're listening to this and you're worried about your bone health, what would be the things where you would say, like, it's really important you go and see your doctor? Okay. Yes. So if they haven't already brought it up with you, I think if you've got a close family relative who's broken their hip or wrist or bone in their spine, if you've got certain medical conditions, so if you've got rheumatoid arthritis or a gut disease that stop you absorbing drugs

36:12properly, obviously, if you're on steroids, if you're a smoker, if you're a heavy drinker, there are a couple of things. Often, if people have some of these conditions, then it will have been flagged already. And there may already have been discussions. But if they haven't, it's worth a conversation to just see whether actually it would be worth taking it further. And it sounds like if you do this DEXA scan, then you actually get a really clear reading of your bone health?

36:43You do. I mean, it's not a crystal ball. So what you get is a measurement of your bone density, which is one of the things, like I say, you can estimate someone's 10-year risk of breaking something without necessarily having that. So you do get information without it. If you have it, then it obviously gives more information that can be helpful. And it gives you like a baseline. But that gives you an estimate of the chances of you breaking something. As I say, it's not an

37:14absolute. So some people will have really quite thin bone density and never break anything. And other people will have what at first sight looks better, but do break something. So there's a whole different discussion around bone quality and things like that. We don't really understand. But the DEXA scan is the really helpful thing in a lot of settings. And there are medications that doctors prescribe that can help with bone density? Yeah. There are several medications. Most of them are what we call anti-resorptive. So they stop

37:50bone breaking down. We have a few, what we call anabolic bone forming drugs. In most settings, they are slightly more restrictive in access for a whole variety of reasons. But most people probably go on what we call anti-resorptive drugs. So there are tablets, there are injections, there are infusions that you can have. Bisphosphonates are sort of the class of drugs. And they can be given as a weekly tablet or as an infusion. We have other drugs that we can use.

38:28You know, a lot of people have heard of a subcutaneous injection called denozumab that's given every six months. That's generally available. Some people do get put on what we call bone forming or anabolic drugs. So PTH injections is one possibility. There's a new drug called romazozumab that became available in a lot of healthcare settings more recently over the last sort of few years. And a lot of people are starting to use that. But different medications suit different people. And some people

39:04would be better suited to some forms of therapy than others. I'd love to talk about what people can do other than hope to get some magic drugs from their doctors. Could we start with exercise? Because you've been talking about this role of muscles. And I think most people listening to this show will be like, well, okay, I know that exercise is good for me, but I think they might be really surprised that it's really a big deal for their bones. I'll never forget the moment that everything shifted for me. I was at a public talk on nutrition,

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40:41proved it supports your digestion, energy, and gut health. That trial helped us develop the formula we have today. Today, Daily 30 is a non-negotiable daily habit for me. So don't put your health off for the future. Go to zoe.com slash Daily 30 and try it today. Yeah. Weight-bearing exercise is good

Diet calcium and vitamin D

41:02for bones. So what happens if you're engaging in weight-bearing exercises? So you're effectively putting the weight of your skeleton through your skeleton. So that's a good thing. And really, for it to be best for bone, what it has to be is repetitive loading that's a bit more than just walking. So that means jumping, step aerobics, running. There are exercises that you could obviously do in a gym setting. Resistance exercise generally is good. Or, you know, a vigorous step. So, you know,

41:37if anyone's ever done any kind of step classes like that, where you're literally going on and off a step. And swimming, sadly, no benefit. Good exercise, but not for the bones because the water's supporting your weight. If you're working with weights in a gym, it is important to be mindful if you've got any problems with your back. So if someone does have low bone density in their spine, we always say to them, be careful how you lift because you don't want to put too much pressure on critical points in your spine. Can we move on to food? Are there any particular nutrients that

42:12people need to make sure they're getting in order to support their bones? Yeah. I mean, there are loads of things. I mean, calcium's obviously the biggie. So you need to have enough calcium in the diet. But then you've got vitamin D, vitamin K, vitamin C, magnesium, all these things. And if I'm thinking about getting calcium from my bones, because I know there's also a whole debate about whether you manage to absorb this properly. Is there any good scientific evidence around the sorts of foods that can, in fact, support my bone health and get

42:46that calcium into my bones? Dairy, obviously, is the classic for calcium. Milk, cheese, yogurt, things like that. Obviously, a lot of people don't consume a lot of dairy. So a lot of foods are fortified with calcium. Now, you're probably aiming for between 800 milligrams and a gram of calcium a day. You know, a lot of people read the backs of labels. So that gives you a sense of the sorts of amount. It does vary a little bit. So, you know, if you're still growing or you're pregnant, there are

43:18other conditions where you might actually need even more than that. If you can aim for that sort of amount of calcium. You know, there are some vegetables that are rich in calcium, things like that. But in general, dairy or fortified foods will be the source. And I understand that there is also calcium in plants. Is that right? Yeah, in some green. There definitely is calcium there. But to get to that level is probably a bit more challenging. Is there any evidence about particular dietary patterns that are linked to sort of healthy bones and reducing the risks of the sort of,

43:54you know, fractures and everything that you were describing? Overall, I would say if you have a balanced diet, that's good. But the dietary pattern that has been probably most studied and most consistently associated with better bone health is the Mediterranean diet. Yeah. You've mentioned vitamin D a number of times. I've definitely heard that vitamin D is good for you. But it sounds like it's got a specific link with bone health. Could you help us to understand that? And therefore, what's the advice to make sure that you're getting what you need?

44:28So vitamin D is important to help you absorb calcium. So vitamin D and calcium go closely together. So if you have very low levels of vitamin D, that is definitely a problem for your bone health, because your bones won't mineralize in the right way. A lot of people have heard of the term rickets. That's what happens if you don't have enough vitamin D. The bones just don't mineralize properly. There's a comparable thing in adults, but it's called osteomalacia. Obviously, it doesn't look quite the same. But again, it's very detrimental. It makes your bones really soft. So vitamin D is

45:01really important. You do get some from diet. A lot of it comes from sunlight to get a really healthy dose of vitamin D. What you would do is have sort of exposed forearms, say, on a sunny day for 20 minutes before you put sun cream on. Obviously, people are very nervous about a lot of sun exposure because we know that there are risks in terms of skin cancer, things like that. But what we would

45:31often say is if you time it carefully, 20 minutes, and then apply your high-factor sun cream, that will give your body a huge vitamin D boost in summer. In winter, obviously, we're reliant on diet and the stores that we've built up. In Australia, where obviously there's a lot of sunshine, there's a very, very high prevalence of vitamin D insufficiency and deficiency because people are very, very careful not to go out into the sun or to use sort of proper sunblock and things like that. So a little bit of

46:05do-dish sunshine is a good thing for your bones. It's hard to get this stuff right, isn't it? It is. It is. There's a lot of conflicting advice.

HRT and weighted vests

46:13Moving on, you talked about what a big deal menopause is. If you take hormone replacement therapy and you're getting more estrogen, does that therefore protect you against this bone damage? Yeah. Yeah. So if you're taking HRT, then you don't have that bone loss that you would otherwise see. And you're protected for the duration of taking the HRT. Bone protection alone is not a good reason to make that decision about HRT or not. But it can feed into the conversation with their healthcare

46:50provider. If a woman goes through premature menopause up to the age of 50, then we're quite keen for people to consider taking HRT because it's viewed almost as sort of like physiological replacement. So sometimes your body's lacking something and medicine is able to replace that, just put it back to where it should have been in health. So HRT up to the age of 50 is viewed more like that. But beyond

47:2150, then the HRT guidance goes more into why are you thinking about doing this? What are the reasons? Why aren't you more pro-HRT? I feel there's definitely been a big shift in terms of the general attitude towards HRT, probably more advanced in the UK than some other countries like the US, but it's definitely shifted in that way. And so I'm just sort of struck that you're saying it's got all of these benefits for bone health and then you're sounding very cautious about it. And I'm

47:51just curious, where is that coming from? Because if you take it for more than five years, you see this slightly increased risk of breast cancer, which is why bone alone would not be enough. It's a small increased risk because there's a background risk in everyone, even if they've never so much as looked at HRT. But it does go up if you take HRT longer term. The reason why we don't use it for just bone is because we have other agents that will protect your bone that aren't linked to any

48:27increased risk of cancer. If someone's taking it because actually it really improves their quality of life, well, fantastic. But just taking it to protect your bones isn't a good idea. Got it. I think we've talked a lot about exercise and diet and how vitamin D fits in and things like this, but I've also seen a bunch of gadgets that are supposed to support bone health. The first one is weighted vests. Should everybody be wearing a weighted vest who's trying to make sure they keep up their bone health? I think there is an emerging evidence base that suggests they may

49:02be helpful. So, I think we probably will still see more people using them. Just to be clear, just sitting on the sofa with a weighted vest isn't going to do it. You have to be walking around. All right. So, weighted vests, surprisingly positive, Elaine. What about whole body vibration plates? They've been around for longer, I would say. I think probably a little bit more nuanced. I wouldn't say there's no place for them. So, if you've got someone who can't do a lot of exercise,

49:36there may well be a place because they will help with muscle and balance as well as bone. But you wouldn't see as significant benefit for bone as some of the other things, to be honest. But in the right population, absolutely. So, final question. If someone listening to this podcast has said, I am worried about my bone health. I want to go and take some action. What would be the first thing that you would advise them to do? Work out what your calcium intake is and check that that's

50:11sitting within the level that it should be. Think about whether your vitamin D levels are likely to be adequate. And if they're not, think about how you could safely raise that. Activity, weight-bearing exercise. That's really important in all of this. Don't smoke. Eat a balanced diet. Just get enough of everything, enough fruit, enough veg, enough calcium, enough protein. Amazing. Elaine, I really enjoyed that. We covered a lot of stuff. I'm going to try and do a summary,

50:42and please correct me if I get any of this wrong. So, the first thing I'm struck by is our bones are alive. And they're doing all these dynamic things, including this amazing impact on my immune system. We need to worry about them because we get to this peak bone health when we're 30. And then, you know, we might keep at that level for a while, but it's going to decline, you know, whether we're men or women. And for a lot of us, you know, living our modern Western lifestyle, we can be in a situation where actually it's been taken away faster than it's been replaced. And this is the

51:18osteoporosis that you were talking about, leaving you with sort of less bone than ideally you would have and therefore vulnerable to fractures. So, unless you've had a scan or you do this questionnaire, this Frax questionnaire, you won't have any idea until you have a fragility fracture, which sounds really bad, which is you fall over from standing height and something breaks, like your wrist or your hip. And one of the reasons it's a big deal is that we all end up both becoming, you know, our bones more fragile and our ability to balance is worse, particularly common if you're a woman,

51:54because once you go through menopause, then your estrogen falls. And then that means that suddenly, for reasons that seem like a bit of a mystery, your body decides to break down your bone faster than it replaces it. We actually now understand there's some interaction between our microbes and our bones. And, you know, I've heard about the gut-brain access, but now we have this gut-bone access. If you have chronic inflammation, you have this raised cortisol, and it's going to lower, again, the pace at which you're replacing the bones versus where it's coming out. And then we talked about lots

52:26of specific advice, which I love. One is, lots of alcohol is bad for bone health, but a little is good. So, I finally found a doctor who's telling me that drinking from time to time is okay. Okay. And interestingly, a bit of weight is also good for bone health. Partly, literally, it's padding if I fall over. Partly that actually I'm getting some estrogen from this fat. But interestingly also, carrying weight is really important because actually that's loading the bone and actually making it, you know, switch on this building process. So, there's some benefit

52:58there. We talked about GLP-1. And I think what you said is, although the data isn't really there yet, you think there's likely to be like a big risk there because of the impact on muscle. So, you're going to be, if you're on GLP-1, you really need to think very hard about how that's going to impact your bones. And then in terms of, okay, so what can you do positively instead of these negative things? Like the number one thing I heard is weight-bearing exercise. It's great to do some cardiac things and some swimming, but here you need to do something like a step class or

53:31resistance exercise, something where you've got real weight and you're sort of pounding your bones. And although that sounds like a terrible thing to do as you get older, you're actually saying, you know, perversely, a bit like exercise, it's really good for you, even though it might feel tiring at the time. Yes. Yeah. You have to watch your joints. That's the only downside because your joints can suffer a bit, but yes. Then we talked specifically around food. And what you said is the number one nutrient for my bones is calcium. We've all heard that. Interestingly, the Mediterranean diet is the diet pattern, which is most associated with healthy bones, but critically actually it's

54:05vitamin D is the more important thing. You actually said try and get 20 minutes of sun exposure on your arms before applying sunscreen, because actually the power of that vitamin D is so beneficial for your bones. And finally, we talked about HRT and what you said is that is protective on bone loss, but you would not be suggesting it to somebody only for bone health because there are other medication that is just for bone health. So it's a sort of added bonus as part of the package when

54:37you discuss with your doctor about why it can be helpful. Perfect.

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56:21Bye.