Latest figures from Cancer Research UK show smoking is the biggest avoidable risk factor, followed by unhealthy diets.
The charity is urging people to consider their health when making New Year resolutions.
Limiting alcohol intake and doing regular exercise is also good advice.
According to the figures spanning five years from 2007 to 2011, more than 300,000 cases of cancer recorded were linked to smoking.
A further 145,000 were linked to unhealthy diets containing too much processed food.