Use of Swedish smokeless tobacco (snus) and the risk of Type 2 diabetes and latent autoimmune diabetes of adulthood (LADA)

Aims It has been suggested that moist snuff (snus), a smokeless tobacco product that is high in nicotine and widespread in Scandinavia, increases the risk of Type 2 diabetes. Previous studies are however few, contradictory and, with regard to autoimmune diabetes, lacking. Our aim was to study the association between snus use and the risk of Type 2 diabetes and latent autoimmune diabetes of adulthood (LADA). Method Analyses were based on incident cases (Type 2 diabetes, n = 724; LADA, n = 200) and population‐based controls (n = 699) from a Swedish case–control study. Additional analyses were performed on cross‐sectional data from the Norwegian HUNT study (n = 21 473) with 829 prevalent cases of Type 2 diabetes. Odds ratios (OR) were estimated adjusted for age, BMI family history of diabetes and smoking. Only men were included. Results No association between snus use and Type 2 diabetes or LADA was seen in the Swedish data. For Type 2 diabetes, the OR for > 10 box‐years was 1.00 [95% confidence interval (CI), 0.47 to 2.11] and for LADA 1.01 (95% CI, 0.45 to 2.29). Similarly, in HUNT, the OR for Type 2 diabetes in ever‐users was estimated at 0.91 (95% CI, 0.75 to 1.10) and in heavy users at 0.92 (95% CI, 0.46 to 1.83). Conclusion The risk of Type 2 diabetes and LADA is unrelated to the use of snus, despite its high nicotine content. This opens the possibility of the increased risk of Type 2 diabetes seen in smokers may not be attributed to nicotine, but to other substances in tobacco smoke. What's new? The risk of Type 2 diabetes and latent autoimmune diabetes of adulthood (LADA) is not significantly affected by the use of snus, despite its high nicotine content. These results raise the possibility that the excess risk of Type 2 diabetes seen in smokers is due to components of tobacco smoke other than nicotine.