Professor Belinda Beck

And so after you've sort of gained your peak bone mass, and let's say that's around 25, we'll split the difference between men and women, say it's about 25,

After that, you sort of plateau for a little bit and then you'll gradually begin to lose bone mass.

Now, at the age around menopause, what causes menopause is the withdrawal of circulating estrogen.

Estrogen is extremely protective of bone because it helps to inhibit or slow down the activity of one of the bone cells that resolves bone.

And that resorption is really important for things like, you know, when you go to the bone bank and get some calcium out,

It's those cells that are regulating that or at least are managing that, removing bone.

But estrogen tends to clamp those cells so that they don't remove too much.

Now, if you have reduced amounts of circulating estrogen, perimenopause and menopause, then those cells have a little bit of a party for a couple of years because they're not as inhibited and they start removing more bone.

So there is a period about five to eight years across the menopause and a couple of years after where women lose bone much more rapidly than they do at the rest of their life.

And then it tends to sort of level out again and you then go on to sort of lose roughly the same amount as men throughout the rest of life.

So this is the reason why osteoporosis is often considered a women's hormone disease.

because of that relationship with estrogen.

But of course, there are all sorts of other things that can contribute to that loss.

That's right, because they don't have that sudden withdrawal of that very powerful hormone.

They do have hormones that are regulating their bone mass as well, and those do tend to, including estrogen, but testosterone as well, and those tend to sort of gradually decline across life as well.

And, of course, this decline is, I believe, very closely associated with the reduction in physical activity that most people undergo as they age.

Yeah, the goal for people like me who believe in exercise as medicine, the aim, if you can see a system that is deteriorating and that seems to be associated with also a reduction in exercise would be to just increase the amount of exercise and you should be able to

reverse things.

Well, the trouble is other people who thought the same thing had tried to add exercise in as a way of moderating or reducing the bone loss that occurs across age.

And for people who had very low bone mass to maybe grow some more.