Note: Separate PDQ summaries on Skin Cancer Screening, Skin Cancer Treatment, and Levels of Evidence for Cancer Screening and Prevention Studies are also available.
Individuals whose skin freckles, tans poorly, or burns easily after sun exposure are particularly susceptible to developing skin cancer. Observational and analytic epidemiologic studies have consistently shown that increased cumulative sun exposure is a risk factor for nonmelanoma skin cancer.[1,2] Organ transplant recipients receiving...
Even its critics admit that snus is less harmful than other forms of smokeless tobacco. And it is far less harmful than cigarette smoking.
So is snus a good thing?
It would be a good thing if everyone who smoked cigarettes or dipped snuff switched to snus instead. It would be a good thing if snus were a way station on the road to quitting all forms of tobacco. It would even be a good thing if kids who would have become smokers became snus users instead.
But despite all of that, mounting evidence suggests snus isn't a good thing -- and may be far worse than they appear.
Snus: Less Harmful, But Not Safe
Cigarettes are the world's most efficient nicotine delivery device. They are also the most deadly. Many of the most dangerous byproducts of cigarettes are created during the burning process.
Much of this risk comes from cancer-causing chemicals called nitrosamines and polycyclic aromatic hydrocarbons (PAH). And snuff products actually deliver more cancer-causing nitrosamines than cigarettes do.
But nitrosamine content is far lower in snus than in snuff, says Stephen S. Hecht, PhD, professor of cancer prevention at the University of Minnesota.
"Snus are made with a special process to help control nitrosamine levels," Hecht tells WebMD.
There's a catch, of course. Carcinogen levels in snus may be lower -- but they are not low.
"Nitrosamine levels in snus are still 100 times greater than levels of nitrosamines in foods like nitrite-preserved meats," Hecht says. "This is not a harmless product."
And there's evidence that these nitrosamines -- or something else in snus -- are causing cancer. In Sweden and Norway, where snus originated, snus users have a significantly higher risk of pancreatic cancer.