Some truths are bone deep
The Silent Disease: it sounds like a good name for a movie. It would have Jeff Goldblum working in a lab desperately seeking a cure for a mysterious affliction. I see Jack Nicholson as the president, looking over the scientist’s shoulder just a bit too much, making the audience wonder if he is somehow complicit in the disease’s spread. This is good, I’d best get the tuxedo dry-cleaned and ready for the Oscars. Sadly though, ‘the silent disease’ is real, it’s nasty and I won’t be moving to Hollywood off the back of it. The silent disease, so called because there are no warning signs or symptoms until bones start breaking, is osteoporosis. Very real and very nasty, I think you’ll agree. Osteoporosis translates roughly as porous bones. When viewed under a microscope, healthy bone looks like a honeycomb. When osteoporosis occurs, the holes and spaces in the honeycomb are much larger than in healthy bone. As bones become less dense, they weaken and are more likely to break with less stress. A key indicator of osteoporosis is when someone falls from a standing position and breaks a bone, typically the hip, wrist or a bone in the spine.
How does this happen? Bones are a living tissue, our bodies are constantly removing and replacing bone in response to a variety of factors and your whole skeleton is replaced roughly every ten years. Those bones that are subject to heavy loads, such as our legs, are the thickest and strongest. Bones beautifully illustrate the notion of form following function, their shape depends on muscular attachments, and lines of pull. (Did you know that if you move the fibula- the smaller, non-weight bearing bone of the lower leg- across into the position of its bigger, stronger neighbour the tibia, it will eventually change shape and size to end up looking like a tibia?) But sometimes that process falters. There are numerous reasons for this. We all lose some bone density as we age due to changing levels of sex hormones and, possibly, reduced load on bones due to lower activity levels, but for some people that loss is more significant, leading to osteoporosis. Who is at risk? In short, everyone; studies suggest that half of women and a quarter of men over the age of 50 will break a bone due to osteoporosis, resulting in an estimated cost of over €10 million per year in Ireland. There are a number of lifestyle issues that contribute to the developing of osteoporosis; lack of dietary calcium, smoking, excessive alcohol consumption, low body weight and physical inactivity are all risk factors. Various medical conditions also have an effect on bone density, including certain cancers, rheumatoid arthritis, diabetes, COPD and eating disorders. Unfortunately, some medications such as steroids can lower bone density, so the treatment for certain diseases can exacerbate the issue further; it’s a cruel world, maybe Jack Nicholson really is involved.
Reducing the risk The good news is that there are things that you can do to lower your risk of developing osteoporosis. Quitting smoking and not drinking too much are probably a given, but worth repeating. We are talking about a bone disease, so being certain to get enough calcium in your diet is crucial. Note that the body needs vitamin D to properly absorb calcium, and while a percentage of this can come from diet, exposure to sunshine is key to its production, so getting outdoors is important. Which brings us neatly to the most important way to maintain bone strength: use them. You will recall I mentioned that bones respond to load, but the reverse is also true. Insufficient weight-bearing exercise is a key risk factor in the development of osteoporosis. The weight-bearing part of that sentence is important, for while swimming and aquarobics can be great exercise, they don’t sufficiently load bones to maintain or improve bone density, thus walking is the minimum requirement. Sports like tennis, golf and bowls that also challenge balance and coordination are better again. Keeping in mind that wrists are susceptible to fracture, exercises that load the upper limbs are important. The easiest way to do that is with weight training. That can be done in a gym, a group class, or by buying some weights and googling upper-body exercises. As long as you do something, you’ll get some benefit.
This post first appeared in The Mayo News