Did You Know?
Bones don’t just grow longer, they also grow thicker – even in adults. The diameter of fingers and long bones can continue to be increased all the way through life if you have too much hGH in your body.
But What is HGH?
This is a growth hormone that is necessary to allow children’s small bones grow into adults’ larger bones. But, too much can mean adults’ bones will carry on growing – not longer, but thicker. Too little hGH in childhood means that a condition of dwarfism occurs. This is known as Pituitary Dwarfism. I’m not being politically incorrect here, this is its official medical terminology. Sometimes, when an adult has too much hGH in their body their lower jaw grows thicker, giving the appearance of an excessively large jawbone. This condition is called Acromegaly.
Sometimes babies inherit too little hGH from their parents’ genes when they are conceived and they are born with a condition that is called Achondroplastic Dwarfism. This affects the long bones because there is not enough cartilage available in the pre-bone formation and, as bone develops from cartilage, this prevents their arms and legs achieving their true length. These children, as they grow, have normal length bodies and shorter arms and legs.
Why Do We Need Bones?
Bones are needed for all sorts of reasons. We all know about bones as support for the softer parts of our bodies. I am sure lots of you know about levering the lid of a tight-fitting jar? Well, the tool you use to do the levering provides what is called a ‘fulcrum’ where the tool meets the jar. This makes it easier to put more force on a small area. Doing this makes it easier for you to apply more force with less effort.
Our bodies are clever because that is exactly what many of our bones do. As an example, you have the top part of your arm attached to your shoulder, then you have your elbow and lower arm and, lastly your hand. Your elbow is the fulcrum and your upper arm is the lever which, when you use your muscles allows pressure to lift up your lower arm and, if you are carrying heavy shopping bags, this lever-effect enables your hands, wrists and lower arm to take the strain with less effort. The setup of this framework also gives your muscles strength because they are attached to your bones. The movement of the bones alters the shape of your muscles and increases pressure placed on them. This is a really good idea because, without it, we would not be able to move about, or carrying on with normal everyday living.
It’s not just that though?
No, it’s not. Did you know that your bones are hollow. This makes your bony framework much lighter and easy to move about than if your bones were solid. However, it is much more important to have hollow bones than just that. In fact, without hollow bones, you would not be able to breath! The insides of your bones are not empty spaces – they are a power house of cell-building and the place where your blood cells are made.
Your red blood cells carry oxygen around your body, obtaining oxygen from your lungs and spreading this oxygen throughout every cell in your body. White cells are very important as well as they fight infection. There are lots of different kinds of white blood cells, each one having different jobs to do. Another kind of blood cell that is made inside the hollow of your bones is the platelets. These are cell fragments really, but they join up with something else to make a sticky glue that helps your blood to clot and, when you cut yourself, help to form a scab to prevent infection getting in and your fluids getting out.
Did you know that you have stem cells that also live inside your bone marrow in your hollow bones. Your stem cells are important because they help to make the collagen which develop into connective tissue. Connective tissue is the tough, stringy tissue that holds your muscles to your bones and enables your skeleton to move.
IMPORTANT STUFF, Stem Cells!
Other cells that are found inside the hollow bones are fat cells and the actual bone cells. Bones are also important because they help essential chemicals get used by the body. Nearly all bone is made out of calcium – in fact, 99% is calcium.
Did you know that your heart is not able to beat properly without the right amount of calcium in your body? Too much calcium is just as bad as too little calcium. Because your bones are made of calcium, they act as the body’s calcium ‘reservoir’, releasing calcium from the bones when your body needs more calcium and removing calcium back into the bones when your body needs less calcium.
Vitamins are Also Important for Growth
Vitamins are very important for growth, especially Vitamin D which enables more calcium from your intestine to be taken up by your body and used to make bone. In children, if there is not enough Vitamin D then children develop rickets which makes children’s legs looked bowed. Not enough Vitamin D in adults can cause the bones to weaken.
Did you that you can get hooked on antacids containing calcium? You can also get a kind of rebound acid reflux from calcium-containing antacids.So that these problems can be avoided, tablets are given a sugary coating and usually contain a mixture of calcium phosphate and Vitamin D.
Collagen is the forerunner to the development of connective tissue which is needed to bind bones and muscles together. In order for your body to be able to make collagen, you need to have enough Vitamin C or Ascorbic Acid in your body. Without enough Vitamin C in your body you would be very ill indeed, and a disease, known as scurvy, would develop. You also need enough Vitamin A and Vitamin B12 in your body to ensure your bones develop properly. However, as with most vitamins, if you have too much that is just as bad. Too much Vitamin A can cause your body to grow too much bone so that it thickens in all the wrong places.
Hormones are Also Important for Growth
There are lots of different hormones in your body and they really do have important jobs to do – so important, in fact, that you could not stay alive without the actions of hormones to regulate all the different things your body is able to do. Most hormones work in pairs, or groups, to carry out a job because they work better that way. Often, when they are working in pairs, they have opposite reactions and are described as being antagonistic.
An example of antagonistic hormones is parathyroid hormone [PTH] and Calcitonin. These two hormones regulate the contents within the blood stream. The reason why these two hormones are important for growth is because of the way bone is able to store calcium and release it into the blood when your body needs to use more calcium for other things. It is the PTH which arranges with a special kind of bone cell to release the calcium from the bones. When enough calcium is available for the body to use and it does not need any more, the Calcitonin ‘turns off’ the stream of calcium that the bone cell is allowing to leave your bones. This allows the calcium in your bones to reduce – there always has to be a balance of the right amount of calcium flowing through your blood stream.
Now, we have all heard of steroids. Your body makes its own steroids: this is what testosterone and oestrogen are. These two hormones also encourage your body to increase the amount of calcium in your bones. This is why you sometimes find bones weakening in the elderly as their bodies make less and less of the steroid hormones during the aging process and can lead to osteoporosis, a condition in which calcium is actually leached out from the bones, leaving a lacy framework of weakened bone
cells and depleted calcium.
Did you that weight lifters can cause their bone growth to either slow down or stop if they take too much of a testosterone supplement? Therefore, if testosterone supplements are taken before adult growth has finished, weight lifters are liable to be of shorter stature than weight lifters of the same age who have never taken testosterone supplementation.
Do All Ageing People Suffer Bone Loss?
No, not all but there are a number of risk factors which can lead to bone loss. Some of these you can do something about and aim to prevent it. Unfortunately, there are some things that can happen anyway – genetics being one of them. As you get older, your body makes less oestrogen, testosterone and hGH.
It is a well known fact by the medical profession that bone is strengthened when it is being stretched – when a load is added to it. It is an equally well known fact that, if bone is not being used to its limit, it will become weaker. The Astronauts found this out for themselves when they went into space and spent time in weightless conditions.
People with small frames and sedentary lifestyles can find themselves at risk from osteoporosis in later life. Sufficient calcium in the diet will help, although there is a recommended daily amount, above which you can do more harm to yourself than good. What you may not know, however, is that, if you take calcium supplements, you also need to take a daily dose of Vitamin D in its active form. Vitamin D comes in different forms – the easiest way is simply to go outside for a daily walk in the open air because your body can absorb the effects of sunlight on your skin and, inside your body, change it into Vitamin D which your body can use. That is an active form of Vitamin D. You can also take Vitamin D supplements.
Be very careful not to take too much calcium, in supplements or any other way. Too much is very bad for you and can result in arteriosclerosis which, in everyday talk, is furry arteries – and that’s not good for your heart!
Taking excessive amounts of antacid preparations are not a good way of supplementing your calcium either – you will simply alter the pH in your stomach. By this I mean that, in your stomach, you have a very strong acid called Hydrochloric Acid. At the top of your stomach you have a muscle which acts a bit like a purse string and keeps all the stuff in your stomach where it should be. However, too much antacid would dilute that acid – but, your body is a very clever thing indeed.If your body sees that the acid in your stomach is not ‘right’ it forms a stronger solution to wash out the antacid. You end up with acid reflux – known in the medical profession as ‘acid rebound phenomenon’
So, How Do Broken Bones Knit Together?
As I said earlier, the body is very clever at looking after its interests! When a bone is broken, you get blood, dead cells and bone cells all ‘homing in’ on the area that is broken. This fills the fracture and actually pushes the broken fragments of bone outwards. This is called a haematoma. Then, you get different kinds of white blood cells which follow and clean up the haematoma. There are three different kinds of bone cells which are able to reproduce and make new bone in the area that was broken.
Three weeks’ after the fracture occurred you will have fibres of cartilage developing at the fracture site. Within these fibres are collagen which is the substance that spongy bone is made from. Next, the spongy bone begins to form at the site of the fracture. However, it can take a good three months for fibrocartilage and spongy bone to develop the hard consistency you expect bone to feel like. The spongy bone is gradually reabsorbed and compact bone deposited as the body builds up sufficient
calcium in the fracture site.
Did you know that your skeleton is continually being renewed and replaced. There is a continual turnover of bone, with up to 1% being renewed at any one time. Every 10 to 25 years the whole of your skeleton will have been renewed due to the continuation of new bone growth. In the elderly, their bones become brittle because there is less protein made. This cause a drop in the production of collagen and makes them more prone to fractures.
A surprising fact is that the growth of your bones is able to respond to environmental situations. This is known as Wolff’s Law. Your bones also have the ability to withstand all sorts of fatigue stresses that could cause ‘microfractures’ due to this constant ability to remodel itself. It is able to do this due to the way your bones are able to absorb and release calcium as quickly as it does due to the very efficient actions of the hormones and the vitamins that regulate your bones’ growth.
Why Does Exercise Stimulate Bone Growth?
If you put a weight on top of your foot and then try to lift your leg up, it is quite a strain because your less is having to work hard to lift your leg with the weight attached. This is good for the bones in your leg because it makes them stronger. This is known as ‘mechanical stress’ and is the reason why your are encouraged to exercise. It strengthens your bones. There is a relationship between the amount of exercise you do and the effect this has on the way your bones grow.
A relationship between the amount of work your bones have to do [e.g. through exercise] and an electrical charge that is generated when your bones carry out that work. It has the fancy name in physics of ‘the piezoelectric effect’ which is an important effect for your bones, but the name is largely irrelevant. There are a couple of reasons why this effect is important to your bones – and to growth, in particularly.
Firstly, the effect is reversible. If you exercise your bones will spark of this electrical charge. When this electrical charge is used in your body, it is able to change the shape of your bone by up to 4% of its volume. After this, the action of the electrical
charge gets quite complicated. However, putting it very simply:
- You undertake some exercise.
- This makes your bones work harder.
- As your bones work harder, they generate an electrical charge.
- This electrical charge permeates across all your bone cells and tissues.
- This encourages your bone cells to increase by up to 4% of their original size.