There's still a lot we need to figure out about e-cigarettes when it comes to their health impacts. But smoking definitely kills, and regulators in the US have a new plan for tackling the problem.

The US Food and Drug Administration (FDA) has just announced a comprehensive new roadmap for regulating tobacco products, and they have dramatically shifted their focus to nicotine addiction. And as part of the new plan, some of last year's stringent regulations on vaping are going to be relaxed.

The FDA regulations for e-cigarette products were announced last May, and they were so stringent that some people were worried it could wipe out the burgeoning industry, despite the fact there's evidence vaping does help smokers with quitting.

But now the agency is changing tack, putting nicotine at the heart of the issue and admitting that when it comes to ways of delivering this addictive substance, there's a spectrum of methods - and some, like traditional cigarettes, are far more unhealthy than others.

"It's the other chemical compounds in tobacco, and in the smoke created by setting tobacco on fire, that directly and primarily cause the illness and death, not the nicotine," said FDA commissioner Scott Gottlieb.

"Even with unanswered questions about benefits and risks, there are now different technologies to deliver nicotine for those who need it, that doesn't bring with it the deadly consequences of burning tobacco and inhaling the resulting smoke."

At the heart of FDA's new strategy will be a push to lower nicotine levels in traditional cigarettes to levels that won't cause addiction. The long-term goal here is to prevent young people from getting hooked when they try their first smoke.

"I've seen the science in this area and believe it holds much promise," said Gottlieb.

"We intend to take a hard look at the existing published literature on this important topic and hear from stakeholders, which could provide the basis for regulatory action."

And while the tobacco industry will be forced to cut back on addictive nicotine levels in their products, the manufacturers of e-cigarettes have been granted an extension on applications for product approval.

"The FDA is committed to encouraging innovations that have the potential to make a notable public health difference," the agency explained in a statement.

"This action will afford the agency time to explore clear and meaningful measures to make tobacco products less toxic, appealing and addictive."

But it doesn't mean the agency is enabling a vaping boom. The agency will still work to develop product standards that will prevent known e-cigarette risks, such as exploding batteries or preventing children from getting easy access to all those sweet-smelling e-cigarette liquids.

On top of that, the FDA will be seeking public input on several aspects of the new plan, including the question of whether the flavouring of tobacco products - say, menthol or cherry cigarettes - makes them more enticing to young people.

They will also look into the best approaches to regulating e-cigarette flavours like bubblegum and gummy bear, which could be appealing to kids.

While the FDA won't encourage you to go and vape to your heart's content, it's certainly a shift towards recognising that e-cigarettes are an innovative way to deliver nicotine, and that regulators need to tackle them differently.

"The overwhelming amount of death and disease attributable to tobacco is caused by addiction to cigarettes – the only legal consumer product that, when used as intended, will kill half of all long-term users," said Gottlieb.

"Unless we change course, 5.6 million young people alive today will die prematurely later in life from tobacco use.

"Envisioning a world where cigarettes would no longer create or sustain addiction, and where adults who still need or want nicotine could get it from alternative and less harmful sources, needs to be the cornerstone of our efforts – and we believe it's vital that we pursue this common ground."

You can find out more about FDA's new plan on the agency's website.