Can heated products reduce smoking prevalence?

Here are some key takeaways from Cochrane’s Report on Heated Tobacco Products (HTPs)

Aman Ali

1/31/20224 min read

It’s important to understand that a heated tobacco product or an HTP is a device that heats the tobacco at a lower temperature than conventional cigarettes. The idea is to heat the tobacco just enough to release nicotine-containing vapor but without actually burning it.

Philip Morris International (PMI), the company behind Marlboro, is considered a pioneer for developing such products, such as the IQOS device, claiming that there are now approximately 20.4 million IQOS users of which, 14.9 adult smokers have switched to IQOS completely and stopped smoking with the remaining in various stages of conversion.

In July 2020, the U.S. Food and Drug Administration (FDA) issued decisions on modified risk tobacco product (MRTP) applications for IQOS and three HeatSticks variants (the IQOS tobacco heating system) submitted by PMI in December 2016. In doing so, the agency found that the issuance of exposure modification orders with reduced exposure claims would be “appropriate to promote the public health and is expected to benefit the health of the population as a whole.

Key takeaways from the Cochrane report to evaluate the effectiveness and safety of HTPs for smoking cessation and the impact of HTPs on smoking prevalence

Do heated tobacco products help people to quit smoking, are they safe for this purpose, and have they led to falls in smoking rates?

Heated tobacco probably exposes people to fewer toxins than cigarettes, but possibly more than not using any tobacco. Falls in cigarette sales appeared to speed up following the launch of heated tobacco in Japan, but we are uncertain whether this is caused by people switching from cigarettes to heated tobacco.

We need more independently funded research into whether heated tobacco helps people stop smoking, whether it results in unwanted effects, and the impact of rising heated tobacco use on smoking rates. 

What are heated tobacco products? 

Heated tobacco products are designed to heat tobacco to a high enough temperature to release vapor, without burning it or producing smoke. They differ from e‐cigarettes because they heat tobacco leaf/sheet rather than a liquid. Many of the harmful chemicals in cigarette smoke are created by burning tobacco. So heating not burning tobacco could reduce the number of chemicals a user ingests. Some people report stopping smoking cigarettes entirely by switching to using heated tobacco.

Why we did this Cochrane Review 

Because cigarette smoking is addictive, many people find it difficult to stop despite the harm it causes. We aimed to find out whether trying to switch to heated tobacco helps people stop smoking cigarettes, and whether it results in unwanted effects. We also wanted to find out whether rising heated tobacco use has affected smoking rates or cigarette sales.

What did we do?

We looked for studies that reported on the use of heated tobacco for stopping smoking, and on unwanted effects and toxin exposure in people asked to use heated tobacco. Here we only included randomized controlled trials, where treatments were given to people at random. This type of study is considered the most reliable way of determining if a treatment works. Finally, we searched for studies looking at changes in smoking rates and cigarette sales following the launch of heated tobacco to market. We included studies published up to January 2021.

What we found

Our search found 13 relevant studies. No studies reported whether heated tobacco helps people stop smoking cigarettes. Eleven trials, all funded by tobacco companies and with 2666 adult smokers, compared unwanted effects and toxin levels in people randomly assigned to use heated tobacco or to continue smoking cigarettes or abstain from tobacco use.

Two studies looked at how trends in cigarette sales changed following the launch of heated tobacco in Japan.

What are the results of our review? 

We do not know whether using heated tobacco helps people to stop smoking cigarettes (no studies measured this).

We are uncertain whether the chances of getting unwanted symptoms from being asked to use heated tobacco are different compared with cigarettes (6 studies, 1713 participants) or no tobacco (2 studies, 237 participants). Serious unwanted symptoms in the short time period studied (average 13 weeks) were rare in all groups, which means we are uncertain about any differences. Toxin levels were probably lower in people using heated tobacco than those smoking cigarettes (10 studies, 1959 participants) but may be higher than in people not using any tobacco products (5 studies, 382 participants).

The launch of heated tobacco products in Japan may have caused the decline in cigarette sales to speed up over time (two studies), but it is unclear whether the fall in the percentage of people who smoke also sped up because no studies looked at this. 

How reliable are these results?

Results are based on data from a small number of studies, most of which were funded by tobacco companies. 

Results on unwanted effects are likely to change as more evidence becomes available. However, we are moderately confident that levels of measured toxins are lower in people using heated tobacco than smoking cigarettes but less confident that levels were higher than in people not using any tobacco. We are also less confident that the launch of heated tobacco caused the fall in cigarette sales to speed up, as results came from a single country.

PMI’s Vision to replace cigarettes with smoke-free products

Having built the world’s most successful cigarette company with the world’s most popular and iconic brands, PMI’s future is being built on smoke-free products with a vision that one day these products will replace cigarettes. They’ve invested over USD 8.1 billion in research and development and have more than 930 dedicated scientists, engineers, and technicians developing and assessing potentially less harmful alternatives to cigarettes.

Smoke-free products have the potential to present less harm than continued smoking but the best choice will always be to quit or not start smoking.