Heated Tobacco Products: Current Evidence of Pulmonary Harm and Lung Cancer Risk

Heated tobacco products (HTPs) are promoted as less harmful alternatives to conventional cigarettes (CCs) because they avoid combustion and reduce the formation of toxic compounds. However, evidence supporting a real reduction in lung cancer (LC) risk remains limited and is largely based on biomarker studies rather than long-term epidemiological data. This review assessed the association between HTP use and LC risk, examined the impact of reduced-exposure claims on consumer perceptions, and evaluated the role of HTPs in smoking cessation. A literature search of PubMed, Medline, and the Cochrane Library identified 26 studies published between January 2020 and June 2025. Available evidence indicates that HTPs generate substantially lower levels of several carcinogenic compounds and are associated with reductions in biomarkers of exposure and biomarkers of potential harm compared with CCs. Risk estimation models suggest that the excess LC risk associated with HTP use may represent approximately 3-4% of that observed among CC smokers; however, these projections rely on indirect measures and carry considerable uncertainty. Although HTPs may contribute to reduced toxic exposure, they are not risk-free and continue to induce biological alterations linked to inflammation and oxidative stress. Reduced-exposure claims influence consumer risk perceptions and may encourage product uptake. In the context of smoking cessation, HTPs may reduce CC consumption but frequently result in dual use rather than complete abstinence. Independent longitudinal studies are required to clarify their long-term impact on LC incidence and public health.