Young people should be banned from buying tobacco products until they are 22, researchers have suggested after a study found those who start smoking before the age of 20 find it more difficult to quit.Scientists said a rise in the minimum age by governments across the world could reduce nicotine dependence.

Young people should be banned from buying tobacco products until they are 22, researchers have suggested after a study found those who start smoking before the age of 20 find it more difficult to quit.Scientists said a rise in the minimum age by governments across the world could reduce nicotine dependence.