Monday, February 19, 2024

Scaremongering’s Forever Effects


With the emergence of nicotine pouches, claims from the 1980s about the health risks of smokeless tobacco (ST) use have reappeared. Nicotine pouches are an important addition to smokers’ options for reducing harm, but it is inappropriate to devalue them by overstating the risks of ST use, such as opining that it causes leukoplakia and periodontal disease.  This is not the case, and I wish to set the record straight.


In 1995, my research group published an article, “Tobacco Use and Cancer,” that discussed leukoplakia: “Oral leukoplakia was originally defined in 1978 by the World Health Organization as a ‘white patch or plaque that cannot be characterized clinically or pathologically as any other disease.’ This definition was recognized as overly broad, and in 1984 a revised definition excluded white lesions such as frictional keratoses and also specified tobacco-induced leukoplakias as a distinct category. Furthermore, [ST keratosis, STK] was separated from smoking-related leukoplakia on the basis of presentation with additional differences in prevalence, frequency of dysplasia, and rate of malignant transformation. STK is common; it occurs in up to 60% of ST users.” (references omitted)

While anti-tobacco zealots never adopted the accurate terminology, preferring the scarier term leukoplakia, findings from 92 biopsies in one of these scaremongering studies were consistent: “All lesions were benign, but one specimen had mild epithelial dysplasia.”  The term mild dysplasia is subjective, so it’s likely that none of the findings were significant.

When our article was published, we were unaware that the infamous study by Winn et al. in the New England Journal of Medicine involved only women who had used powdered dry snuff (here).  That misleading study led nearly everyone, including health professionals, to mistakenly believe that moist snuff (dip) and chewing tobacco use among men causes mouth cancer.  For confirmation of that fallacy, see the October 2016 report by Annah Wyss of the National Institute of Environment Health Science and 20 government-funded coauthors (discussed here) that found that American men had no excess mouth cancers associated with dipping or chewing tobacco (Odds Ratio, OR = 0.9), while women, who mainly use powdered dry snuff, had a 9-fold elevated risk (here). 

Periodontal Disease

The CDC describes gum or periodontal disease as “mainly the result of infections and inflammation of the gums and bone that surround and support the teeth.”  The same scaremongering study cited above also reported that “gingival recession and attachment loss [4 mm or more] were greater in sites adjacent to lesions in [ST] users.”  These findings aren’t the same as infections and inflammation in and loss of the supporting bone, which is periodontal disease.  In fact, a comprehensive review by Kallischnigg et al. in BMC Oral Health concluded, “Two of four studies report a significant association of snuff with attachment loss and four out of eight with gingival recession. Snuff is not clearly related to gingivitis or periodontal diseases. Limited evidence suggests chewing tobacco is unrelated to periodontal or gingival diseases.” (emphasis added)

These two conditions, leukoplakia and periodontal disease, pale in comparison to lung cancer and heart attacks, so why am I focusing on them?  Because misinformation, particularly about safer smoke-free cigarette substitutes, has a dangerously long shelf-life.

I have dedicated the past 30 years to setting the record straight about ST use, but the American public remains grossly misinformed due to misinformation published decades ago.  For example, the National Cancer Institute Health Information National Trends Survey documents that 86% of Americans don’t believe – or don’t know – that ST use is less harmful than smoking (here).  Similar fake science now inundating the medical literature about newer smoke-free products, if not stopped, will have the same long-term effects. Public health and tobacco experts need to approach misinformation about tobacco risks as seriously as physicians counter quackery in medicine. 


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