Attachment 12.3 Smokeless tobacco and harm reduction

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Sweden has a similar prevalence of tobacco use to its neighbours, but one of the world's lowest tobacco-attributable mortality rates. Some observers have suggested this phenomenon, known as 'the Swedish experience' is explained by the increasing use of smokeless tobacco by Swedish smokers, a trend that has corresponded with a decline in smoking prevalence.1, 2 However, this interpretation has been debated.3

The most common form of smokeless tobacco used in Sweden is a moist oral snuff called snus, which is available either as loose tobacco or pre-packaged portions similar to teabags. Unlike other smokeless tobacco products marketed in the US and other countries, snus is pasteurised rather than fermented and stored under refrigeration to minimise bacterial growth. These processes greatly reduce the formation of nitrosamines, the main carcinogens in tobacco. This, and the absence of the combustion products associated with smoking (e.g. carbon monoxide), probably reduces the risks of cardiovascular disease, chronic obstructive pulmonary disease and cancer compared to smoking. Unlike cigarettes, snus does not produce environmental tobacco smoke or carry a risk of causing accidental fires.

Long-term prospective cohort studies have observed a lower risk of many tobacco-related diseases and overall lower mortality in snus users compared to smokers.4-6 Snus use appears to carry some residual risks, albeit lower than for smoking, of pancreatic cancer,6, 7 cardiovascular disease8 and possibly diabetes9, 10 compared to no tobacco use. Snus use is also associated with dental disease and gum lesions, called leukoplakia, but these appear to disappear on discontinuation of use.11

The Swedish experience has prompted some researchers to suggest that smokers who are unable to quit should use low-nitrosamine smokeless tobacco products, such as snus, to reduce tobacco-related harm. This proposal is contentious.

Some health professionals do not feel that the existing epidemiological studies showing a lower risk of tobacco-related disease in snus users are sufficient to support snus use. Others are concerned that the difference in potential harm between snus and smoking has not have been fully described in existing studies. Some believe that any health risk from snus, no matter how small, is too great for its use to be encouraged. However, the difference in healthy life expectancy and overall mortality risk between smokers who quit all tobacco and smokers who switch to smokeless forms appears to be small.12, 13 Sweden has also achieved substantial reductions in tobacco-attributable mortality despite a high prevalence of snus use.

Cultural adaptability

Snus has had an extensive traditional use in Sweden where it was known as 'the poor man's luxury'. Whether the Swedish experience will transfer to Australia, which has never had a significant smokeless tobacco tradition, is uncertain. There are also behavioural aspects of smoking that may not be adequately replaced by snus use. For example, smoking offers something to do with the hands and is easy to do while engaging in other social activities such as drinking and talking. Snus is simply placed under the top lip and left there until it is removed. Talking and drinking while using snus requires more skill than smoking to keep the tobacco portion in place. The small bulge visible in the upper lip during snus use may also lack the glamour of smoking.

Ethical issues

Snus is not harmless and it is as addictive as smoking. Many health professionals feel it is unethical to promote the use of a substance that offers no direct benefit to the user (the indirect benefit is the absence of smoking), is addictive and still carries risks. Proponents of tobacco harm reduction counter that it is unethical to deny smokers access to a product with substantially lower risks than smoking and to deny them accurate information about the benefits of switching to snus, particularly as cigarettes, the most harmful tobacco product, are readily available.14

Opponents of snus argue that quitting all tobacco use is the only health advice that doesn't carry any risk. Proponents of snus argue that many smokers fail to follow this advice and that 'quit' or 'keep smoking', sometimes described as 'quit or die', should not be the only options available.15

While it is debatable whether health professionals should recommend snus use to smokers, it is arguably unethical to provide inaccurate information about the relative harms of snus use and smoking due to the mistrust such misinformation can create.16, 17 The challenge is avoiding messages that snus is 'less harmful' being misinterpreted as meaning that it is 'not harmful'.

Individual- and population-level harm

Using snus may reduce tobacco-related disease in individual smokers who make the switch, but widespread use could still result in population-level harm in a number of ways. Firstly, if snus proved more popular among non-smokers than smokers, then overall harm could increase. Secondly, the promotion of snus could keep current smokers smoking (instead of quitting) or lead some non-smokers to commence smoking. This is the most likely way in which snus promotion could produce population harm because the large difference in health risk between smoking and snus use means that a very large number of non-smokers need to use snus to offset the health gain achieved from a smoker switching to snus.12, 18 In Sweden, snus use very rarely leads to smoking in non-smokers.2 It is unknown whether similar patterns of use would occur in Australia.

Tobacco manufacturers have argued that they should be able to market and promote snus in order to inform smokers of the benefits of switching. This is an important issue because if snus is to have a population level benefit, a sufficient number of smokers need to make the switch. However, promotion of snus use via tobacco industry advertising may increase overall tobacco use, possibly including smoking among current non-smokers. Some cigarette manufacturers have also produced 'snus versions' of their most popular brands of cigarettes. How to allow snus to be promoted for tobacco harm reduction without allowing the promotion of the corresponding cigarette brand will be a challenge.

In countries where tobacco advertising is allowed, cigarette manufacturers have promoted dual use of smokeless and smoked tobacco products as a way to get around public smoking bans. Such 'dual use' could reduce or even negate any health benefit from snus use by deterring quitting. Public smoking bans not only protect non-smokers from environmental tobacco smoke, but have the added benefit of encouraging smokers to quit due to the inconvenience these bans produce. Some of these quitters may therefore be encouraged to keep smoking as they can get through the inconvenient times with a short-term alternative.

Some tobacco control professionals have countered that dual use is not necessarily a negative if it encourages smokers to try snus and leads to some switching completely. Whether this is a likely outcome remains to be seen. Clearly, addressing the need to inform inveterate smokers of the benefits of switching to snus without deterring would-be quitters or encouraging smoking in non-smokers requires careful regulation of information to avoid these potential negative consequences.

An unnecessary distraction?

Some tobacco control professionals view snus and tobacco harm reduction as a distraction from the main task of encouraging smokers to quit tobacco use and discouraging uptake.19 Tobacco smoking, they point out, has declined in Australia without snus. Supporters of snus argue that it offers an additional strategy that may hasten the decline in smoking and may reach those smokers who have been resistant to traditional tobacco control strategies or have been unable to quit tobacco use despite repeated efforts.

What about 'clean' forms of nicotine?

Nicotine replacement therapy (NRT) products, such as gum, lozenges or inhalers have also been suggested as a long-term alternative to smoking. Because these present lower risk than snus, it has been argued that there is no need to allow snus use.

This argument ignores the possibility that snus may be more attractive to smokers than NRT. Snus is a purely recreational tobacco product which delivers nicotine in similar amounts to the user as smoking. It may, therefore, be a better substitute for cigarettes for smokers who want to continue using tobacco recreationally. NRT is also primarily marketed as a medicine for short-term assistance during cessation. Currently available NRT products are low dose which prevents them from providing a sufficient 'buzz' for smokers who want to use nicotine recreationally. Higher dose recreational 'clean' nicotine products face substantial regulatory barriers because of their addictiveness. Pharmaceutical companies, who manufacture NRT, are unlikely to see the marketing of a recreational, addictive product as their core business. Pharmaceutical companies may also be concerned that long-term use of high dose nicotine products may carry a higher health risk than short-term use of low dose NRT, which has been established as safe.

In Sweden, snus is a more popular smoking cessation aid than NRT gum or patches and smokers who use snus are more likely to quit than smokers who use NRT.2 Among the possible reasons for this greater popularity and higher success rate are: the social acceptance of snus use in Sweden, its lower cost (snus is taxed at a lower rate than cigarettes) and the higher nicotine delivery from snus compared to NRT. Using NRT to quit smoking may also be stigmatised by some smokers who see the use of a medication to quit as a sign of drug addiction. Snus, which is not a medication, may be seen as a 'smarter choice' rather than a sign of weakness. As uptake of NRT in Australia remains relatively low,20 a product that may be more attractive to smokers and more effective, even if marginally riskier, could increase the number of quitters and therefore produce a greater population-level benefit.

What should the public health response be?

The epidemiological evidence and the Swedish experience suggest that snus may be an important tobacco harm reduction opportunity. Uncertainty around its potential effect on other tobacco control policies indicates a need for caution in pursuing this goal.