Do the significantly lower number and levels of harmful chemicals in IQOS tobacco vapour also mean lower levels of such chemicals in the body? If you reduce the level of harmful chemicals in IQOS tobacco vapour, it would make sense that switching completely to IQOS from cigarettes reduces exposure to these harmful chemicals. To prove this, we measured biomarkers of exposure for a number of these harmful chemicals in thousands of smokers who participated in our clinical study programme (some switched to IQOS, while others either continued smoking their cigarette brand or quit for the duration of the study). These studies show that when smokers switch to IQOS, their body absorbs significantly lower levels of harmful chemicals, which in turn results in favorable changes in a number of risk markers selected because of their known association with smoking-related diseases. But it doesn’t end.​

Once IQOS is available in the market, the research moves from being conducted in a pre-market setting to a real-world post-market setting. There, we look at how the product is being used and by whom in order to complement our pre-market findings and to do our best to identify and prevent use or uptake by unintended audiences. After years of commercialisation in many countries, the available data confirms our pre-market observations, in particular in terms of IQOS’ appeal to adult smokers and the relative lack of interest in former and never smokers. We also monitor reports of health effects now that the product is used by millions of adult users. Long-term studies will eventually help us to evaluate the potential disease–specific risk reduction of IQOS. Gathering data to answer this question takes time, but it’s the right choice. So far, all the data we’ve seen points in the right direction.​