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Bone Basics
Bones hold your body up and give it shape. Without bones you would be just a blob of organs and skin! Bones are made up of calcium and phosphorus minerals and living tissue. It's not the same sort of tissue that you use when you have a runny nose though! The way bones are made means that they are strong and can withstand impacts such as jumping, skipping, running, falling and bumping into things.
Below is an image of the human skeleton showing common names and some scientific names for the bones.
The Skeleton
The skeleton is made up of two different types of bone. These are cortical bone and cancellous bone (see Figure 2).
- Cortical bone is thick and forms the outer surfaces of bones. Eighty per cent of the weight of the skeleton is cortical bone.
Figure 1: Leg bone shaft - Cancellous bone is spongy and looks a bit like honeycomb. Cancellous bone is found in the vertebrae (the bones that make up your spine), as well as at the ends of the long bones in your arms and legs and within flat bones such as your shoulder blades. It gives bone strength in the same way as steel rods in concrete. Cancellous bone also contains bone marrow, which is where red blood cells are produced.
Figure 2: Basic bone structure
The skeleton is living tissue which acts like a storage tank for calcium. The best way to keep this storage tank filled is to top up with calcium every day to make sure there is enough to grow and maintain unbeatable bones. If the food and drinks we consume do not contain sufficient calcium, the body withdraws stores from the bones to meet its needs.
Your skeleton is growing right now! Did you know that it becomes seven times bigger from the time you are born to the time you become a teenager?
That's a huge difference. Just imagine getting seven times more pocket money!
Because your skeleton is growing so quickly it needs heaps of calcium and other bone building nutrients. When you become a teenager you actually need even more calcium, because this is the time you gain the most bone - they get much longer and wider in the teenage years. Strong bones are also important to support larger and bigger muscles that are developing as you grow.
It is very important to keep consuming enough calcium-rich dairy foods to help grow and maintain healthy, strong, unbeatable bones for your whole life. Eating and drinking enough dairy foods will make you less likely to break a bone, and reduce your risk of developing osteoporosis (brittle bones) later in life. That seems like a good idea, doesn't it?