Recap: Strengthen your bones and avoid osteoporosis | Professor Tim Spector & Professor Cyrus Cooper
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Hello and welcome to Zoe Recap, where each week we find the best bits from one of our podcast episodes to help you improve your health.

Today we're discussing bone health. How strong is your skeleton? It's a tough question, and often we only find out the answer when a bone breaks. The reality is many of us have weak bones. Osteoporosis affects one in four people over 50, significantly increasing their risk of painful and debilitating fractures. So what can you do to keep your bones strong as you age? Professor Tim Spector and Professor Cyrus Cooper explain how you can tailor your lifestyle to maintain a strong skeleton.

Osteoporosis is the commonest bone disorder worldwide, and it's associated with reduced bone density, a disruption of the microarchitectural content of bone, and an increased risk of fracture. The fractures that typically arise from osteoporosis are fractures of the hip, the spine, and the distal forearm or wrist.

Those three fracture sites account for about half of all fractures in older people, and the other half are from all the other sites combined around the skeleton. The places you're talking about feel to me like not the most common places that people tend to break their bones when they're children or in their 20s or 30s. Is that...? So that's exactly correct.

In their 20s and 30s, trauma plays a much bigger role than bone density. So this is like falling out of a tree or... Having a road traffic accident. Breaking your nose. Yeah. Whereas as you get to later life, particularly for women above the age of 50, the average age of menopause, and men more so after age 70...

Low trauma or, in fact, absent trauma is associated with many of the fractures. And those truly are ones due to bone fragility. So what does it mean to break a bone without trauma? I think of it always being like you... No, it means just rolling over in bed, for example. You can actually trigger a vertebral fracture. Wow. Just by doing that or twisting in a certain way. Most of our vertebral fractures present...

on an incidental finding on a radiograph. And a vertebra fracture, where is my vertebra? Your spine. And typically, the bones that break in your spine, the spine contains small vertebral bodies all the way down. The mid thoracic, which is the middle part of the back, and the lower lumbar, which is down towards the pelvis,

Those are the main sites at which osteoporotic vertebral fractures occur. That's what a wedge, so you have these sort of square looking vertebrae, lots of them all on the spine, which act as these sort of shock absorbers. And when you get a fracture, it sort of crunches in on itself.

And so if it does it in a certain direction, you can end up with a bent spine. That's a major example of us thinking about, you know, in the past, like old ladies sort of being bent over. And some of these old ladies don't feel any pain. It just gradually comes on. They don't notice it. It happens at night or whenever. You can have, you know, five or six of these without any pain at all. And that's why it's often called the silent epidemic syndrome.

which for this reason, people are actually getting fractures without knowing about it and not realizing what the cause is and not realizing that it's preventable. So it's a slightly terrifying idea that you might just roll over and, you know, things break in your bones. Could you help me, Cyrus, understand what's going on? Why does this start to happen now, but, you know, nobody in their 20s is worried about this happening? All of us gain bone density through our childhood and adolescence. And what does bone density mean?

So if we were to look inside a bone, we'd find that there are layers of collagen. And those collagen protein layers have gaps in them within which the calcium sits. In osteoporosis, there's a reduced amount of collagen and there's also a reduced amount of mineral. And that's what makes the bone weak. Right.

Why are you talking about these fractures in these particular bones, right? Like I've got bones all over. Why these ones? Well, these fractures are particularly rich in what is called trabecular bone, which is a honeycomb end of the long bones, which loses bone fastest.

and which when it gets subjected to trauma fractures earlier. So I'm thinking about my very simple, you know, almost cartoon picture of a skeleton with like long bones, the little round bits at the end. And you're describing sort of those round bits at the end of the things that are getting... Just beneath the round bit at the end, that part of the bone, so the fractured neck of femur...

the area just underneath the head of the femur, which is what gives way and breaks. Diet has a big role to play in osteoporosis. And if you looked at some meta-analyses where you're combining lots of these studies together from all these cohorts around the world, you find that once you've accounted for lots of other factors, the quality of the diet has a big impact on the risk of fracture.

And it's not things like the amount of calcium in the diet. It's not things, you know, the amount of zinc or any one item. It's the sort of things we talk about in this podcast all the time, you know, having plenty of vegetables, being protective. It's about having small amounts of processed food. It's not having lots of junk food, not having lots of fizzy drinks. So it's that health quality aspect which has come out

globally when you look at the meta-analyses as being really important. And it's significant, is it, this difference between a high-quality diet and an average diet? Absolutely, yes. It's not sort of like 2% that only scientists can see? No, we're talking sort of 30%, 40% differences between these extremes. These are really big ones, but it's highlighting that the same things that are good for many other diseases are also good for osteoporosis and bone. But it's also telling us that it's not

you know, as we used to think, all about calcium or all about protein. It's actually the quality of the diet, the combination of foods rather than these individual ingredients which people use to sell supplements. Completely, that's right. And this is true at all ages as far as I know. So, I mean, you've done some of this work in older people. Children, adolescents, older adults.

uh, the, the, the move towards dietary quality as compared with, uh, micronutrients that are specific for bone health has definitely been the direction. I think that's really interesting because I think, you know, one of the things that was most surprising to me in my journey from Zoe over the last seven years is, you know, seven years ago, I assumed that there are these very specific vitamins because they're the things that are on the, you know, the

back of the pack and that you see being sold in the stores and that those were really mattered everywhere and i think i've subsequently discovered that you know there's a hundred thousand chemicals in food and and all these other sorts of things even before they hit your microbiome and they make all these other things

But I had at least until this morning thought, well, at least calcium is really important for bones. You know, I'm sure I learned that when I was 11. And what you're saying, I think, is even there, your total diet may be really important, but it's not because there's calcium in that diet. It's something to do with all the different things. Just because the calcium is in the bone does not mean that modifying it by increasing its level in your stomach will actually have any impact on your bones. Exactly.

And Cyrus and I had been brought up on this myth that calcium was all important. And we just assumed it was a fact. And it's only really in the last 10 years with all these massive analyses and people starting to look at diet differently that

a more global holistic way of looking at food, that we start to see that actually calcium doesn't even make the list of contenders. So it doesn't matter whether you actually drink milk or not. It's about the quality of your diet. It's really interesting. What you're saying is the calcium does really matter in my bones. Like I need to have the calcium is what you're saying. But in order to get more calcium in my bones, like eating or drinking more calcium doesn't help.

You were saying like, if the road's dug up outside, I can't just give you a bunch of asphalt. That doesn't make it happen. Like I need someone to come with that fancy machine that lays it. And so I sort of need to pay the person who's going to lay it rather than just say, oh, I'll eat some asphalt. This will solve the problem. Eat more gravel, yeah. That's fascinating. Now...

I think one question a lot of people will be saying is, is there anything specifically, however, that I should be thinking about adjusting? So imagine that maybe I'm going through perimenopause, I've been through menopause. Is there anything that we know about sort of

way that I might want to think about changing my diet or is this just like overall I need to have care more about the quality of my diet perhaps than when I was younger? I think the number one message is care more about the quality of your diet, try and get more plants now because they are all these sources of other minerals. You know, as you said, there are 100,000 different chemicals in food. So the more diversity we get, the more we are going to get a balance of these things. And so that's why a rich balance of particularly plants is

is going to give you all these, whether it's zinc or magnesium or phosphate, in exactly the right amounts that your body needs because we're evolved to take it up and absorb it in those ways. That's more important than saying, okay, I'm going to forget all that. I'm just going to take some vitamin D capsules and drink a pint of milk. So I think in a way that's where we've got it wrong in the past.

We've said, well, there's one quick fix here, where actually it's going back to, you know, there isn't a quick fix. It's this holistic idea. Again, it comes back to food quality. But I think get the food quality right, and then Cyrus will tell us there's some really good exercise tips now that I'd always...

stages of life that are really important. So could you talk about that? Because actually we haven't mentioned exercise yet. One of the reasons we have a skeleton and bones is for the muscles to work off and for locomotion, for walking around, running, evading hunters in the olden days. That role of exercise is

is very close to the starting function of the skeleton itself. We already know that when we start in the earliest stages of life weight-bearing,

we can start to see an acceleration in the mineralization of the skeleton at those very early stages. Toddlers' first steps. Yes, absolutely. So you're saying once the toddler starts to walk, suddenly their bones get stronger. They've been weightless in utero. They come out and they start to ambulate and you can see a discernible change in their mineral accrual from the blood, if you like, into the skeletal tissue.

Thereafter, there's a rapid gain up to age 25 examples. The serving arm of a tennis player is 15 to 20% higher bone density than the non-serving arm.

A stroke or reason for paralysis of a limb leads to massive demineralization of the bones. So I just want to make sure, because I think everyone sort of is familiar with the idea that their muscles shrink if they're not using them. But what you're saying is that if I use...

My arm, for example, your tennis example, is like I'm using that arm more and hitting something with it. My bone is actually going to get bigger and stronger or denser and stronger. Absolutely. That's exactly what happens. That's crazy. If you send someone into space...

their skeleton will dissolve with calcium leaving the bone and being passed out in the urine. Because they're weightless. Because they're weightless and therefore no action of the muscles on the bone. Weight-bearing exercise is crucial really at all stages of life. And I think that's the sort of number one lesson people need to learn. And

What we also learned from another experiment is it doesn't have to be huge amounts of time. You don't have to run marathons or anything. That's the point. Of course, you'll do well if you run marathons, but if you just walk an hour three days a week as an older person, you'll still have an improvement in both your bone density and your falls risk, your muscle function and falls risk, such that you'll have an impact on fracture. ♪

That's all for this week's recap episode. You can find a link to the full conversation in the episode description. If you want to make smarter food choices for your body and transform your health for life, why not try Zoe membership? The first step is easy. Take our free quiz to find out what Zoe membership could do for you. Simply go to zoe.com slash podcast.