Each year in May, the world recognizes World No Tobacco Day — an occasion the World Health Organization (WHO) uses to implore countries to ban all forms of tobacco advertising, promotion and sponsorship.

In many places the promotion of tobacco and smoking has been banned. From the UK and Australia to South Korea and Vietnam, you won’t see tobacco products illuminated on billboards, glorified in the ads shown before movies in the cinema, or portrayed as a harmless habit for the cool and carefree — as they once were — at train stations and bus stops.

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Only 48 countries in the world have implemented a complete ban on tobacco advertising

But as regulations around smoking toughen in many parts of the world — and many, like plain packaging in Australia or the graphic health warnings in the EU, are shown to be highly successful — anti-smoking campaigners are debating whether these restrictions should be extended to film and television. Many are advocating for movies and shows with tobacco scenes to be given an adult content rating.

Smoking on Netflix at all-time high

A July study by the US anti-smoking organization Truth Initiative found Netflix featured nearly three times as many smoking scenes in its shows most popular with 15- to 24-year-olds in the 2016-17 season as it had the previous season.

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Overall, 92% of the shows analyzed showed tobacco scenes, up from 79% in the 2015-16 season.

"Tobacco advertising, over many, many years, has been very successful in getting young non-smokers to start smoking," says Jamie Hartmann-Boyce, a smoking behavior researcher at the University of Oxford in the UK. "And especially since [advertising] has been clamped down on more and more, the tobacco industry has had a history of looking for other ways to advertise."

Although there is no evidence of tobacco industry sponsorship of these depictions, a Concave Brand Tracking analysis of Netflix's Stranger Things found it featured more than 100 visible brands in its third season.

Truth Initiative estimated that around 28 million young people were exposed to tobacco through these Netflix programs, and through an "analysis of peer-reviewed studies" calculated that "exposure to tobacco use in movies is responsible for 37% of smoking initiation among young smokers."

A similarly high prediction was made by a recent Canadian study, focusing on movies. Its authors estimated that exposure to smoking in movies between 2002 and 2018 will recruit a cohort of 185,000 Ontario youth aged 0-17 to become smokers, resulting in an additional $1.1 billion (€995 million) in healthcare costs over their lifetime.

Netflix has sparked a fire for its frequent depiction of cigarette smoking in shows popular with young people

Can movies really 'make' smokers?

But not all tobacco-control researchers agree that the link made between exposure to smoking in movies and smoking uptake is a reliable one.

Simon Chapman, an emeritus professor at the school of public health at the University of Sydney in Australia, whose expertise is in tobacco control and policy intervention, says such claims are "crudely reductionist" in the way they ignore the widespread exposure of young people to smoking in other situations.

Chapman says that while there should be more awareness about how gratuitous depictions of smoking can serve to normalize it, it is extremely difficult to prove that seeing smoking in movies directly causes young people to start smoking. He's also not convinced that adult classification is an effective way of preventing youth from watching such content.

"I'm not a fan of public health wading into film, literature, theater or music and censoring what people are allowed to depict,'" he told DW, expressing his concern that public health censorship of the arts was a slippery slope.

Normalization and glamorization in question

Hartmann-Boyce also told DW that it can be difficult to "draw the line between art and advertising." However, as the media landscape changes and streaming platforms become further-reaching, she says that — direct link or not — it is important to keep in mind where products are being placed.

"As a public health body 10 years ago or so, we had a more solid grasp on what was going on in terms of product placement," she says. "But now that the technology is changing and all these new links are emerging, it's a lot less simple."

Given that more than 8 million people die from smoking each year, making it a leading cause of death, illness and impoverishment, Hartmann-Boyce says an increase in tobacco use on screen is a cause for concern.

"I don't think any of those movies are sharing the message that smoking is good for you," she said. "But I think what they are doing is they're normalizing it — in some cases they're glamorizing it — and we know that that can increase smoking rates."