What Happened to Vaping in Japan: The IQOS Revolution and Its Discontents

Japan is the most important nicotine policy laboratory that most Western researchers haven't studied. While the global debate has focused on vaping—its benefits for adult smokers, its risks for youth—Japan has followed a radically different path. Nicotine-containing e-liquid is effectively prohibited under Japanese pharmaceutical law, making the vaping products that dominate Western markets technically illegal. Instead, Japan has become the world's largest market for heated tobacco products, led by Philip Morris International's IQOS. The result has been a natural experiment with no close parallel: what happens when a country with a large smoking population gains access to a non-combustible nicotine product that isn't vaping? The answer, emerging from a decade of Japanese data, challenges the assumptions of both sides in the global nicotine debate.

The Japanese cigarette market collapsed with unprecedented speed following IQOS's nationwide launch in 2016. Cigarette sales, which had been declining at roughly 2% annually, began declining at 8–10% annually—a rate of decline with no precedent in any major market. By 2023, cigarette sales in Japan had fallen by over 40% from their 2015 peak, and IQOS had captured roughly 30% of the tobacco market. The decline was driven overwhelmingly by existing smokers switching to heated tobacco, not by new users initiating with the product. Surveys consistently found that IQOS users were almost exclusively former smokers, with negligible uptake among never-smokers—a pattern strikingly different from the youth-driven vaping epidemic in the United States. The Japanese experience suggested that, under the right conditions, a non-combustible nicotine product could dramatically accelerate smoking cessation without creating a youth epidemic.

Why did IQOS succeed in reducing smoking in Japan without attracting youth? Several factors appear to have been decisive. First, the regulatory environment: Japan's pharmaceutical ban on nicotine e-liquid meant that IQOS competed not with a diverse vaping market (which might have fragmented consumer preferences) but directly with cigarettes. The choice for Japanese smokers was binary: keep smoking, or switch to heated tobacco. Second, the cultural context: Japan has strong social norms against behaviors that inconvenience others, and heated tobacco's reduced odor and sidestream aerosol made it more socially acceptable than smoking in a culture where blowing smoke on others is considered deeply rude. Third, the marketing environment: Japan's restrictions on tobacco advertising are less comprehensive than in many Western countries, allowing IQOS to be marketed aggressively as a 'cleaner,' 'less harmful' alternative—claims that are restricted or prohibited in many other jurisdictions. And fourth, the absence of youth-oriented flavors and marketing (the IQOS marketing emphasized technology, sophistication, and social harmony rather than candy flavors and youth culture) limited its appeal to adolescents.

The public health community's response to the Japanese IQOS experience has been notably muted—and, when it's been expressed, skeptical. The WHO's position on heated tobacco is that there is 'no evidence' of reduced harm, a claim that's technically defensible (long-term epidemiological evidence doesn't exist) but practically misleading (the toxicological evidence of reduced exposure is robust, and the Japanese cigarette sales data is difficult to explain except as harm reduction at population scale). The reluctance to acknowledge the Japanese experience is understandable: heated tobacco is an industry product, the long-term health effects are unknown, and endorsing it would validate the industry's 'harm reduction' narrative. But the reluctance has costs. Ignoring or dismissing the Japanese data doesn't make it go away. It just ensures that the global policy debate proceeds without engaging with the most important real-world evidence available.

The Japanese experience also illuminates the limitations of heated tobacco as a harm-reduction tool. Heated tobacco is almost certainly more harmful than vaping, because it involves heating actual tobacco leaf, which generates tobacco-specific nitrosamines and other toxicants at levels that, while substantially lower than cigarette smoke, are substantially higher than e-cigarette aerosol. The toxicological hierarchy—cigarettes > heated tobacco > e-cigarettes/NRT—is well-supported by the available evidence. A public health strategy that maximizes harm reduction would prioritize the lowest-risk products (vaping, NRT) over medium-risk products (heated tobacco). Japan's policy framework, by effectively banning the lowest-risk nicotine products while allowing the medium-risk ones, has achieved remarkable smoking reductions but has also locked millions of former smokers into a product that's probably less safe than the alternatives they might have chosen if they'd been available. The Japanese outcome is good—dramatically better than continued smoking. But it's not optimal, and the difference between good and optimal matters when it's measured in cancer cases over decades.

The most uncomfortable implication of the Japanese experience for the global tobacco control community is that the tobacco industry, under the right regulatory conditions and with the right product, can be a vehicle for accelerated smoking cessation. This is not an argument the tobacco industry should be trusted, or that its motives are altruistic, or that its products should be exempt from regulation. It's an observation that the fastest smoking decline ever recorded in a major market was driven by industry-developed, industry-marketed, industry-sold products. The mechanism was not public health messaging or pharmaceutical cessation aids—it was consumer substitution driven by product availability, marketing, and the alignment of commercial incentives (PMI makes higher margins on IQOS than on cigarettes in Japan) with public health outcomes (reduced smoking). The question this raises—which product is the vehicle matters less than whether smokers switch to it—is deeply uncomfortable for a public health establishment that has defined itself in opposition to the tobacco industry. But it's the question the Japanese data forces us to confront.

The Japanese IQOS revolution is not a model to be uncritically replicated. Japan's pharmaceutical ban on nicotine e-liquid, which created the conditions for IQOS's dominance, is poor public health policy that denies smokers access to the lowest-risk nicotine products. The lesson of Japan is not 'ban vaping and let the industry sell heated tobacco.' It's that accelerated smoking cessation is possible, at a speed far exceeding historical trends, when smokers are offered satisfying, accessible, non-combustible alternatives—and that the regulatory framework should maximize the availability and appeal of the lowest-risk alternatives while minimizing the risks of youth uptake and industry manipulation. Japan achieved the first part of that equation (accelerated smoking decline). It didn't achieve the second (the lowest-risk products remain unavailable). The global challenge is to do both.