The scientific evidence

In a cigarette, the tobacco is burned by combustion at temperatures over 900ºC, releasing a highly complex mixture of gases, particles and compounds and leaving behind a grey ash.

In contrast, THPs heat tobacco to much lower temperatures (~200‒300ºC). As there is no combustion, the aerosol consists mainly of water, glycerol, flavourings, and nicotine. Also, odour is greatly reduced, and there is no ash.

By not burning the tobacco this dramatically changes the composition of the aerosol. Comparing cigarette smoke with glo aerosol, the weight of evidence shows that the levels of toxicants were reduced on average by 90-95%.*†

To date, most research has been conducted by industry scientists, but an increasing number of independent reports are broadly aligned with these findings and support the role of THPs as a less risky*† alternative to smoking.

In 2022, we published the results of a year-long study which showed that smokers switching exclusively to glo, achieved significant and sustained improvements in several indicators of potential harm compared to those who continued to smoke.

The full results, which were published in Internal and Emergency Medicine, build upon the favourable changes reported at three and six months. The improvements observed were sustained over the 12 months of the study, adding to the weight of evidence that supports glo as a less risky* alternative for adult smokers who would not otherwise quit.

Based on the early indicators of disease measured, smokers who switched completely to glo instead of continuing to smoke showed:

•  Significant and sustained reduction in a biomarker with the potential to cause DNA damage associated with lung cancer
•  Significant and sustained reduction in white blood cell count, an inflammatory marker associated with early development of CVD and other smoking-related diseases
•  Sustained improvement in HDL cholesterol associated with reduced development of CVD
•  Significant and sustained improvement in an indicator of lung health (FeNO)
•  Significant and sustained improvement in a key indicator of oxidative stress, a process implicated in several smoking-related diseases, such as CVD