There's hardly a week goes by without cancer making the news - either new ways of beating it, or another report on ways to avoid it. But why is cancer so common, and what can we do to reduce our chances or falling victim to this aggressive, invasive disease?

Cancer is so dangerous because of three properties. It is:

Aggressive (the cells grow and divide)
Invasive (cells invade and destroy adjacent tissues)
Metastatic (it spreads to other locations in the body)

Cancer is usually caused by abnormalities in the genetic material of cells, which may be due to the effects of carcinogens (e.g. tobacco smoke, radiation, chemicals, or infectious agents), or through genetic abnormalities present from birth.

However, because of the complex interactions between genetics and exposure to carcinogens, it is hard to predict who will get what form of the disease.

With this disease now responsible for up to 15% of all deaths, it is worth trying to reduce your susceptibility. Risk factors include:

Alcohol consumption
Smoking
Lack of exercise
Obesity

Given that these are the same risk factors that contribute to high blood pressure and heart disease, it makes sense to make every effort to pay attention to these areas.