The Dose23:21What do I need to know about osteoporosis?
Osteoporosis is sometimes called a silent thief — you usually don’t know you have it until you break a bone.
Yet the disease is common: one in three women and one in five men in Canada will suffer a fracture due to osteoporosis in their lifetimes.
Osteoporosis is a disease where your bones become weak and can break more easily.
“It’s not painful. It doesn’t make you tired. So you really don’t have symptoms just because you have low bone density,” Dr. Carrie Ye told Dr. Brian Goldman, host of CBC’s The Dose.
“What you will feel is a broken bone, so that can be painful,” said Ye, a rheumatologist and medical director of the Multidisciplinary Bone Health Clinic at the Kaye Edmonton Clinic.
Experts say there are many risk factors for developing osteoporosis, and being aware of our bone health early in life can help prevent it.
How do our bones renew themselves?
Our bones constantly undergo a process of being broken down and built up again — an ongoing struggle for renewal that keeps them healthy and strong.
It’s a race between two types of cells: osteoclasts, which eat away at bone, and osteoblasts, which build bone.
“To have healthy bone, you want constant turnover of eating away, but then replacing it with new bone,” said Ye.
You can think of it like road work, said Dr. Angela Cheung, a senior physician scientist and professor of medicine at the University of Toronto and the University Health Network.
“Even with our daily activities, like running up and down stairs and doing whatever, we can sort out micro-damage to the bones. And so the bones respond by digging up the potholes,” said Cheung.
The crew blasting away the old, damaged road is the osteoclasts, eating away the damaged bone to make space for new bone.
“Then another team — the bone formation cells — comes in to fill the bone,” he said.
What is osteoporosis?
When the osteoclasts start winning the bone battle and the osteoblast cells don’t get replaced fast enough, that’s when you can develop osteoporosis.
Health-care providers typically diagnose osteoporosis after a fragility fracture, but it can also be diagnosed through a bone density scan.
Osteoporosis is actually a disease — a chronic disease — and it’s not just because someone’s aging.– Nese Yuksel, professor
A fragility fracture is when someone breaks a bone with little to no trauma, and experts say if you break a bone this way you should be assessed for your risk of having another fracture within the next ten years.
In Canada, health professionals often use a risk assessment tool called FRAX to look beyond bone density at other factors that could lead to a fracture, such as family history and medical conditions.
Guidelines from Osteoporosis Canada say you should start getting bone density scans at age 65, unless you have reasons for doing so sooner.
Those reasons could include a medical condition or certain medications that put you at risk of osteoporosis, said Ye.
What causes osteoporosis?
There are many risk factors for osteoporosis, experts say, and one of the biggest is aging.
Once women go through menopause, and men are in their early 60s, we lose about half a per cent of our bone density every year, said Ye.
Women are at risk of developing osteoporosis earlier in life due to perimenopause and menopause, when their estrogen levels drop.
“As soon as we lose our estrogen levels, what happens is our osteoclasts start to get more active,” said Nese Yuksel, a professor in the faculty of pharmacy and pharmaceutical sciences at the University of Alberta who works at the same bone health clinic as Ye.
The osteoclasts are the cells that break down the bone. During perimenopause and menopause, they start to inch ahead of the bone formation cells, and women lose an average of five to eight per cent of their bone density.
As people age, they may also start exercising less, which can lead to bone loss.
However, there is a myth that developing osteoporosis is a natural part of aging, said Yuksel, but that isn’t the case.
“Osteoporosis is actually a disease — a chronic disease — and it’s not just because someone’s aging,” Yuksel said.
Another big risk factor is genetics.
“Having had a parent who’s fractured a hip is one of the biggest predictors that you’re going to fracture a hip,” said Ye.
How can you prevent osteoporosis?
Throughout childhood and young adulthood, bones are being built, which is why experts say it’s important for children to get enough calcium and vitamin D, along with regular physical activity.
“Like height, you achieve something called peak bone mass,” said Cheung.
That peak bone mass happens in our late twenties or early thirties, and if children don’t get enough exercise, they may end up with a lower bone mass, he said.
The importance of exercise for bone health continues throughout our lives, with a particular focus on weight-bearing and balancing activities, and less focus on aerobic activity, experts say.
When we put stress on our bones, that stimulates them to build bone density.
Examples of weight-bearing exercises are walking — particularly with Nordic poles — jogging, strength training and dancing.
It’s also important to have good balance and core strength to prevent falls, said Yuksel, and exercises such as tai chi can help.
Diet also plays a role
Enough calcium and vitamin D are key to preventing osteoporosis, experts say.
“We always recommend dietary calcium if you can. That can be really difficult if you’re lactose intolerant or can’t have dairy products,” said Ye.
Other good sources of calcium include dark green vegetables, almonds, fortified plant-based beverages, and canned sardines and salmon with the bones.
Osteoporosis Canada recommends that adults aged 50 and over get 1,200 milligrams of calcium per day. If you can’t get that much through your diet, you can also take a calcium supplement, Ye said.
For the first time since 2010, Osteoporosis Canada will release new guidelines for the treatment and management of the disease in fall 2023.
“There’s a lot of new material over the past 10 years and we want our guidelines to be evidence-based,” said Cheung.