Harm reduction in smokers: what the WHO and science say

The official WHO position on tobacco (2025)

In June 2025, the World Health Organization published its new report on the tobacco epidemic: 6,100 million people are protected by at least one MPOWER measure at best-practice level — the highest coverage ever recorded.

The WHO’s official position is clear: the only strategy that completely eliminates the risk of smoking at a population level is complete and definitive cessation of tobacco and nicotine use. There is no safe level of tobacco consumption.

The MPOWER programme: the 6 tobacco control measures

MPOWER is the WHO’s technical framework for country-level tobacco control, developed from the Framework Convention on Tobacco Control (FCTC). Its six measures:

What harm reduction in tobacco actually means

Harm reduction is a public health approach that seeks to minimise the negative consequences of risk behaviours in people who are not ready or willing to give them up completely. In smoking, it applies to smokers who keep smoking and who may benefit from strategies that reduce their exposure to harmful compounds.

Most of the damage from conventional tobacco comes from combustion: when burned, tobacco generates thousands of chemical compounds, more than 70 of which are known carcinogens. Nicotine itself is not the main cause of harm — the smoke is.

Habits that reduce risk according to scientific evidence

The following habits are supported by scientific evidence as reducers of exposure to harmful compounds. They do not eliminate the risk of smoking — they reduce it.

• Do not smoke the last third of the cigarette Tar concentration increases towards the end of the cigarette. The last third generates up to twice as many harmful compounds as the first. Putting it out at two-thirds significantly reduces total exposure.
• Do not inhale deeply or hold smoke in Inhaling deeply or holding smoke in the lungs increases absorption of particles and toxic compounds. A short, shallow draw reduces exposure at the “first filter” of the bronchi.
• Reduce the number of cigarettes per day The relationship between number of cigarettes and risk is not perfectly linear, but reducing the amount smoked — especially combined with the other measures — reduces the total burden of harmful compounds.
• Avoid inhaling in unventilated enclosed spaces Second-hand smoke in enclosed spaces concentrates pollutants. Smoking outdoors or with good ventilation reduces your own exposure and that of people nearby.
• Do not mix with substances that increase combustion Some mixtures alter the temperature and type of combustion, generating different profiles of harmful compounds. Tobacco alone, well-cured, is the starting point with the least toxicological complexity.

Papers and filters: do they matter for harm reduction?

This is the most relevant question for the roll-your-own smoker: does the choice of paper and filter affect exposure?

Rolling paper

Rolling paper contributes a small but non-negligible proportion of total smoke. The relevant factors:

• Unbleached vs. bleached paper Bleached paper uses chemical compounds (dioxins and organic chlorine in older processes) that can generate additional compounds in combustion. Modern oxygen-bleached papers are considerably cleaner, but unbleached paper — in its natural colour — still contributes the fewest additives to smoke.
• Hemp paper Organic hemp fibre paper burns more slowly and evenly, at a lower peak temperature. Some studies suggest that cooler combustion generates fewer pyrolytic compounds. It is the preferred option for smokers seeking to minimise the paper’s impact on flavour and combustion profile.
• Paper thickness Thinner paper = less paper burned per unit of tobacco. The paper’s contribution to total smoke is lower with ultra-thin papers.

Filters

Conventional cellulose acetate filters retain some of the smoke particles. Activated carbon filters go a step further: the porous structure of activated carbon selectively adsorbs some volatile compounds, including certain aldehydes and aromatics from the smoke. This does not make the cigarette harmless, but it alters the profile of compounds reaching the lungs.

The debate on e-cigarettes and heated tobacco

Non-combustion tobacco products — e-cigarettes (vapes) and heated tobacco devices (IQOS, etc.) — are at the centre of current public health debate.

The WHO position

The WHO warns that available epidemiological data do not confirm that these products reduce smoking at a population level. In some countries, their use has coexisted with an increase in conventional smoking, especially among young people. The WHO does not recommend them as a cessation tool.

The position of some health bodies

The UK NHS and some European respiratory societies acknowledge that, for smokers who cannot quit using other methods, switching to a combustion-free device may reduce exposure to some harmful compounds in conventional smoke. But they also warn of unknown long-term risks.

The debate is not closed. What is consensus: nothing is more effective at reducing tobacco harm than stopping its use.

Frequently asked questions