Some people may think that because they see some people who have smoked all there lives NOT getting cancer, then they might aswell carry on. I suppose its related to the damaging philosiphy of \"there is some hope, lets cling to it.\"

Well here\'s a little fact. The majority of people have cancer RIGHT NOW, probably me aswell. That wort? Yes thats a form of cancer, but luckily for you its one that won\'t turn malignent. To explain this properly, I\'m going to have to explain some basic genetics, so if you bore easily...

The main problem is DNA, its very fragile and prone to getting damaged. We call things that damage DNA carcinogens, tar from tobacco is one of them, but there are many others. Damage to a cells DNA will most likely result in the failure of its function, in other words it will just die and be reabsorbed. DNA in our bodies is getting damaged all the time, but because this damaged usually has no affect outside that particular cell, we have nothing to worry about. But on the rare occasion that the mutation allows the cells to continue functioning, problems start to arise.

But before I got into that, there is hope! We have evolved a safety mechanism, there is an enzyme that travels along DNA correcting any faults.

Even though the damaged cell may continue functioning, its still nothing to worry about, it will probably live out its life and just expire, or have its error corrected. However, if certain genes are effected it can have serious reprocusions, these geens are called oncogenes. The most dangerous of these are the genes responcible for DNA error correction, and mitosis. Its most likely to be a DNA correction gene that starts a cancer, otherwise the damaged would be repaired just like the other times. When the correction measures have been destroyed, it starts a downward spiral. If the next mutation (yes next, once the correction measures are down, your DNA has no defence to the damage that occurs dayly) affects a replication gene (cell division) then it is likely that the cell will start to reproduce itself rapidly. This not only drains your bodies resources (mitosis requires a lot of energy, plus the resulting tumour will require a lot of blood), but it also it creates a vast number of other cells with the same problems (in this case, it has limited DNA repair capacity, and replicates very fast), thus greatly incerasing the chances of FURTHER mutations. At the moment the tumour is benign, its not all that dangerous and its spreading. But if it is continually exposed to carcinogens then it is likely further mutations are likely to occer. For example, cancer spreads by breaking through the epilthilial layer of the tissue that it resides in, probably into the bloodstream, and then sticking to and penetrating another surface and replicating there. But if the DNA of the cells in the tumour are no longer exposed to the carnicogens, then the mutations neccessary for the cells to penetrate other epithilial tissue will not occur.

As the mutations continue to take hold of the tumour, your body recognises it as a \"foreign entity\", and will destroy it. But only if it gets the chance! Continual smoking is exposing your cells to life threatening carcinogens, there is no way to tell if your cancer has a proper hold of your body untill it is almost too late, why take the risk?