A new study has discovered nicotine-filled vapes could help people give up smoking faster.
However, researchers from Lancet Respiratory Medicine say the e-cigarette had to be used in conjunction with other nicotine-based therapy - patches, gum, lozenges - to be most effective.
University of Auckland Associate Professor and lead investigator Dr Natalie Walker says the research is also significant because of the 1124 participants, 40 per cent identified as being Māori.
"The NZ Health Survey 2017/18 found more Māori women smoked daily compared to Māori men, so it was encouraging to see so many Māori women engaging in the trial in an effort to quit smoking."
The main outcome from the trial was measuring who was "smokefree" for six months.
People who used patches combined with a nicotine e-cigarette were more likely to be smokefree for that period than those who used patches combined with a nicotine-free e-cigarette.
The use of both methods was also most preferred by those who took part in the survey.
Side effects from using the products were "uncommon and decreased with time", she said.
As for whether vaping was safe, Dr Walker said vaping was a harm-reduction tool to help people dying from smoking tobacco.
"Vaping is less harmful than smoking.
"In NZ, 5000 people die each from smoking-related diseases. The best of our knowledge no one in NZ has died from vaping."
There had been cases of death and acute illness in the United States, however, Dr Walker said they weren't caused by the devices, "but rather what was put into the e-cigarette".
The cases involved a contaminant appearing in products sold on the black market and not in retail or vape stores.
"It's therefore important that vapers don't purchase e-liquid from the black market ... only buy from reputable retailers."
She also urged that vaping be only used by people who have smoked tobacco.
Researchers broke the participants up into three groups before randomly assigned their particular method - patches, patches plus e-cigarette or patches plus nicotine-free e-cigarette between March 17, 2016, and November 30, 2017.
They were advised to use their products two weeks before quitting before continuing for another 12 weeks.
People using the nicotine vapes were more likely to go without smoking for six months, between 7 and 17 per cent, as opposed to nicotine-free vapes, between 4 and 10 per cent.
"That may not sound like much of an effect, but it adds up.
"If we promoted using patches with a nicotine e-cigarette in New Zealand, where about 512,000 people smoke regularly, we would support 15,000 to 36,000 more people to become smokefree.
"That's a lot of people whose lives could be changed for the better."
The new study is the first ever to test the effectiveness and safety of using nicotine e-cigarettes with nicotine patches as a combination therapy for nicotine replacement.
"Nicotine is what makes people want cigarettes but it's the tar and around 4000 other harmful chemicals in tobacco smoke that cause cancer, heart disease, lung problems and other smoking-related illnesses.
"It's those other chemicals, not the nicotine, which kill up to two out of every three smokers," Dr Walker said.
In New Zealand around one in eight - 13 per cent - of adults aged 15 or over smoke tobacco every day.
Rates were higher for people living in deprived areas - 23.2 per cent, Māori women, 35 per cent, Māori men 27 per cent and Pacific Island peoples 20 per cent.
However, 18.9 per cent were also young adults, aged between 25 and 34.
Study co-investigator, University of Auckland Professor Chris Bullen said although e-cigarettes didn't work for everyone, their findings showed they should be offered as one of the many smoking cessation aids available.
Dr George Laking, also a co-investigator for the study, said it was the largest randomised trial in the world of e-cigarette use involving indigenous people.
"The trial has shown the feasibility of combining nicotine e-cigarettes with patches for Māori who seek to quit smoking."
Commenting around "big tobacco" companies' aggressive marketing tactics, Dr Walker said they were "trying to catch up" in the market and wanted new customers before the Government changed regulation around the advertising, promotion and sale of vaping products.
"The majority of e-cigarettes sold in New Zealand are not tobacco company e-cigarettes. The new heat-not-burn tobacco products currently promoted by the tobacco industry are not the same as e-cigarettes or vaping.
"E-cigarettes are less harmful than heat-not-burn tobacco products."
A sub-sample of 226 participants were asked whether they smoked in their homes or cars.
Overall 87 per cent said their home was completely smokefree while 57 per cent said their car was smokefree.