I remember as a kid I threw myself off monkey bars in the playground and tried to convince my parents my arm was broken because I thought having a cast was cool, but apparently my bones were made of tougher stuff as I never did break a bone. This week Dairy Australia and Osteoporosis Australia are promoting us all to take some time to think about keeping our bones healthy so they don’t break when we get older.
We tend to think of bones as hard, never changing parts of our body. Actually, like some people’s houses, your bones are constantly under renovation and being rebuilt. As children, bones are built up faster than they are broken down and the bones grow. As an adult your bones stop growing but they are still constantly being broken down and rebuilt. Then, after about 45 or 50 years old the reverse starts to happen and our bones start breaking down faster than they are building up. These leads to bones becoming weak or brittle, a condition called osteoporosis. Because this is controlled by hormones osteoporosis tends to happen to women earlier and more often than men; 50% of women and 30% of men over 60 suffer from osteoporosis.
Osteoporosis is a concern because you can’t see, or feel your bones getting weak until you fall. Because the bones are brittle they break very easily. It takes a long time to recover and a lot of older people stop being able to get around and become dependent on family and friends to help them.
The good news is by eating calcium-rich foods and with regular exercise and some sunshine, you can help keep your bones stronger for longer so that you’re out playing soccer with the grandkids well into your old age!
The ‘Calcium Bank’
While many people know that calcium is one of the building blocks of bones, what they may not realize is that it’s being deposited and taken out again all the time, just like a bank account, to be used by other parts of your body. Calcium is used by your heart, muscles and nerves, so if you don’t get enough from your diet, your body will start to take some from ‘the bank’, and you may develop osteoporosis as an older adult.
It’s important to keep your ‘calcium bank’ topped up to grow and keep strong bones. Teenagers in particular need to be depositing calcium rapidly to grow bones, so it’s a concern that a recent study showed that most Australian teenagers are not getting the recommended amount of calcium*. Studies show that this can put girls in particular at risk of osteoporosis later in life.
Make a calcium deposit each day!
Australian guidelines recommend different amounts of calcium at different times in life:
Children....................... 700 mg = 3 serves of dairy or equivalent
Teenagers.....1000 –1300 mg = 3 - 4 serves
Adults........................ 1000 mg = 3 serves
Women over 51........1300 mg = 4 serves
Adults over 70...........1300 mg = 4 serves
Dairy products like milk, cheese and yoghurt have lots of calcium. If you don’t eat dairy products or are looking for more variety some alternatives are calcium-set tofu, tinned sardines or salmon (with the bones) and bok choy.
A serve might be:
a cup of (low fat) milk or fortified soy milk (skinny latte, fruit smoothie or on your cereal)
a small tub of yoghurt or rice pudding
2 slices of cheese in your sandwich or salad
1 cup bok choy
160 g tofu
Vitamin D is also important for healthy bones because it helps take up calcium from our food and store it in our bones. Strangely, it’s not really a vitamin at all but a hormone made by your body and activated by sunlight on your skin. As we get older our skin is not as efficient at activating vitamin D, and without the active vitamin D our bodies don’t absorb as much calcium as when we were younger. That’s why we need more calcium than when we’re a young adult.
There has been some research results lately that show even in a sunny country like Australia people may not be getting enough Vitamin D. For a great summary of Vitamin D check out The Scoop on Nutrition post on Vitamin D.
Other things that help keep healthy bones are regular exercise, not smoking, and avoiding excess caffeine.
For some healthy bones fun for the kids visit the Dairy Australia Healthy Bones website here
*(‘Kids Eat, Kids Play’ study from 2007)