Quitting is difficult but beneficial at any age!

Even at 60, giving up smoking almost completely removes
 the risk of lung cancer, research has found.  People who
 have not already developed the condition are unlikely to
 do so after they quit. Professor Julian Peto, of the Cancer
 Research Institute, told a conference in London that the
 finding indicated a need for new public health strategies.
 Currently they focus mainly on dissuading children from
 starting but fail to encourage adults to quit, he said. 

Public health focus...

The Cancer Research Campaign backed the call to focus
 efforts on persuading adults to give up.  The government
 is due to publish a white paper on public health in the
 autumn, hich will cover strategies to prevent smoking.  
Jean King, head of education for the campaign, said: 
"We have been pressing the government to put more on 
cessation in its white paper."  She said: "People should
 realise that there are benefits at all ages. "After 10 
years the risk of cancer is significantly reduced, and it 
only takes one year to cut the risk of heart disease."  
She added that although nicotine was extremely addictive 
and hence difficult to give up, there were plenty of support
 bodies to help smokers quit.  The finding came as the result
 of long-term research projects such as the 40-year British
 Doctors Study.  They allow doctors to compare the health of
 60-year-olds who stopped smoking at 50 with that of smokers
 of the same age. 

Smoking triggers cancer...

The reason for the advantages of quitting applying at any
 age could lie in the sequential way lung cancer develops.
  Tobacco can trigger changes to cells. A series of these
 changes must occur to trigger lung cancer, so if someone
 gives up smoking before all of them have taken place, they
 are unlikely to develop the disease.   Professor Peto said:
 "It has not been until the last year that we could see the
 full horrors of what smoking does."  He said that half of 
all smokers die as a result of their tobacco use, not a 
quarter as was previously thought.  Other factors that could
 cause the cancer were a poor diet lacking in fresh fruit or
 vegetables and prolonged exposure to the sun.