Cigarettes produce tar, IQOS doesn’t. "Tar" is the residue from smoke after a cigarette has burned. IQOS does not produce tar because it heats tobacco instead of burning it. It generates an aerosol residue that is fundamentally different from "Tar" and consists of significantly lower levels of harmful chemicals.* Switching completely to IQOS is less harmful than continuing to smoke.
IQOS heats tobacco to around 350°C instead of burning it for a simple reason: the burning of tobacco, at temperatures that can reach 800°C, releases high amouts of harmful chemicals. IQOS gently heats the tobacco to 350°C to release the taste of real tobacco, but with no smoke or ash and less smell.
With IQOS there's no ash, no lingering smell and no negative impact on the indoor air quality. It's a better choice in every sense. Cigarettes burn tobacco, which produces high amounts of carbon monoxide. IQOS doesn’t burn tobacco, producing on average 98% less carbon monoxide (CO) and significantly lower levels of other harmful chemicals compared to cigarettes.