New research has cast doubt over the usefulness of vapes in tackling smoking. 

A study looking at 25 years of data on New Zealand teenagers shows there was steep decline in youth smoking rates before vapes came on the scene. 

Instead of displacing smoking, it suggests vapes are a gateway to cigarettes for young people. 

University of Auckland research fellow Dr Lucy Hardie says these figures are unsurprising, considering young people are primarily targeted by the advertising.

"They use social media influencers and really glamourous advertising to really target young people, because that's where you make your money. If you can get young people - you've potentially got a lifetime of addiction." 

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