In a Policy Forum, Nizan Packin and Sharon Rabinovitz highlight the social, political, and economic risks of rapidly growing commercial prediction market (PM) platforms, such as Polymarket and Kalshi, and call for informed regulatory action. “The window for precautionary action is closing: Each week of billion-dollar PM activity, integrated into core information infrastructure without oversight comparable to that of regulated gambling, prolongs a large uncontrolled experiment on users,” write the authors. For many years, economists and computer scientists praised PMs as refined tools of collective intelligence, particularly within academic and institutional settings where they were used to generate accurate forecasts. However, a 2024 U.S. court decision permitting event-based political contracts on commercial platforms marked a turning point, accelerating the rise of large-scale, gamified markets designed for mass participation. Unlike their research-focused predecessors, these modern platforms often prioritize user engagement and profit, and by late 2025, PMs were handling more than $2 billion in transactions each week, with major events attracting wagers totaling in the hundreds of millions. According to the authors, these rapidly growing platforms raise growing concerns, including the potential for democratic manipulation, the incorporation of gambling-like mechanics, and risks to public health stemming from addictive design features.

Here, Packin and Rabinovitz discuss these concerns in detail and highlight the need for evidence-based regulatory attention. “This public health risk flourishes through systematic regulatory failure,” write the authors. “PM platforms function as ‘regulatory entrepreneurs,’ designing products to leverage legal ambiguities between gambling and financial law.” The authors note that commercial PMs can undermine democratic integrity by enabling manipulation, unequal participation, and distorted political signals. Foreign actors may legally trade on election outcomes, while thinly traded markets allow relatively small bets to shift probabilities and create misleading impressions of consensus, influencing voters, media narratives, and campaign dynamics. Weak oversight also enables insider trading risks tied to sensitive government information, which creates the ability to profit from real-world events and may even create incentives to influence the outcomes themselves. Moreover, these platforms increasingly resemble gambling systems, despite being framed as tools for forecasting, which may drive broader social and economic risks for those who use them, particularly individuals with addictive tendencies. According to Packin and Rabinovitz, PMs now occupy a pivotal juncture; they could remain valuable tools for informed decision-making if responsibly governed – or, if unchecked, they could become sources of behavioral and democratic harm. The scientific community, having contributed to their development, bears a responsibility to guide their ethical boundaries, advocate for evidence-based regulation, and ensure that innovation does not outpace accountability.

For reporters interested in topics of research integrity, author Sharon Rabinovitz notes, “One of the most underacknowledged integrity issues in addiction science is structural: stigma and implicit moral judgment constrain funding for the very research needed to ground policy and regulation in evidence. This is especially acute for behavioral addictions, where powerful financial interests consistently outpace the science and actively shape the regulatory landscape. Gambling, despite its well-documented public health impact, remains chronically under-researched relative to its regulatory urgency; trading platforms and prediction markets present an even more pressing gap, aggressively normalized yet almost entirely unexamined for addiction liability. Without greater public investment in independent research, regulation will continue to lag behind industry, repeating the mistakes of sectors that shaped the evidence base in their own favor before oversight could catch up.”

Podcast: A segment of Science's weekly podcast with Nizan Packin, related to this research, will be available on the Science.org podcast landing page [http://www.science.org/podcasts] after the embargo lifts. Reporters are free to make use of the segments for broadcast purposes and/or quote from them – with appropriate attribution (i.e., cite "Science podcast"). Please note that the file itself should not be posted to any other Web site.

Key highlights:

A central debate in tobacco policy is whether taxing e-cigarettes might unintentionally drive vapers back to traditional cigarettes, which are linked to increased risk for many cancers, heart/blood vessel and lung diseases.

A new study found that higher (pre-tax) base prices and higher taxes both reduced e-cigarette use, measured by product units purchased and the amount of nicotine consumed.

The study did not find statistically significant evidence that raising e-cigarette prices led to greater cigarette consumption among the general adult e-cigarette-using sample.

Tobacco researchers say that given the complex e-cigarette marketplace with different product types, a one-size-fits-all tax may not be sufficient. Policymakers could consider tiered tax designs to achieve specific public health goals.