Researchers surveyed over 5,800 smokers who tried to quit without medication or support between 2009 and 2014. They found that 20% of those who used e-cigarettes reported quitting smoking conventional cigarettes, compared to only 10.1% of those using nicotine replacements like gum or patches. Senior author Prof. Robert West said e-cigarettes could improve public health by helping more smokers quit, as the health risks are much less than from smoking.