A new study published in the current issue of the International Journal of Cancer suggests that in contrast to the previous thinking, the health consequences of the use of snus are substantial and that snus-related health risks cannot be lightly ignored (see: Roosaar A, Johansson ALV, Sandborgh-Englund G, Axell T, Nyren O. Cancer and mortality among users and nonusers of snus. International Journal of Cancer, published online April 15, 2008).
Previously, it was thought that snus posed very low health risks and that there was not even a clear association between snus use and oral cancer. The new study, based on a 30-year follow-up of almost 10,000 Swedish men, found "a statistically significant increase in the incidence of the combined category of oral and pharyngeal cancer among daily users of snus (incidence rate ratio 3.1, 95% confidence interval 1.5-6.6). Overall mortality was also slightly increased (hazard ratio 1.10, 95% confidence interval 1.01-1.21)."
The researchers concluded that "Although the combined previous literature on snus and oral cancer weigh toward no association, this population-based prospective study provided suggestive evidence of snus-related risks that cannot be lightly ignored" and that "Even if smoking is without question a much greater threat to health than snus our research rejects the view that the use of Swedish snus is in principle without risk."
The Rest of the Story
Because of the large sample size and long-term follow-up in this study, it carries a lot of weight in terms of evaluating the overall literature on this topic.
This study reports that even though the overall mortality risk associated with the use of snus is not high, there is a three-fold increase in oral and pharyngeal cancer risk among daily snus users. This is a substantial increased risk and the results bring into serious question the previous thinking that snus use is not associated with oral cancer. And because the risks of conventional smokeless tobacco are much greater than those of snus, the oral cancer risk from such products are likely to be even higher than observed in these snus users.
These results are important because they question the thinking that smokeless tobacco (or snus in particular) should be promoted as an alternative to smoking cigarettes. They also bring into question the statement that smokeless tobacco is a safer alternative to smoking. While it may be safer in terms of overall mortality, it does not appear to be safer in terms of oral cancer risk. Thus, the unqualified statement that smokeless tobacco is safer than smoking does not appear to be warranted.
This study also highlights the point I made in an earlier post in which I criticized a former oncologist who took on a leadership position at Swedish Match for having the gall to tell the public that he was now working to promote the public's health. The rest of the story is that he is, in fact, promoting oral cancer among his customers. That is hardly what I would call promoting the public's health. In fact, he has switched from fighting cancer to helping promote it. And despite the fact that he can rightly claim that the overall mortality from snus use is much lower than that from smoking cigarettes, he has no business claiming that he is now in the business of promoting the public's health. Sellers of cancer-causing products are not in the business of health promotion. And we need to keep that straight.