The extensive use of smokeless tobacco and the worldwide occurrence of diabetes mellitus (DM) poses significant public health obstacles. A comprehensive review of the literature was undertaken to assess epidemiological research, clinical trials, and meta-analyses that examine the link between smokeless tobacco use and DM. The key results indicate that the biological constituents of smokeless tobacco may interfere with the process of glucose metabolism and lead to an increase in insulin resistance. An association between consumption levels and diabetes risk is evident, with higher levels of usage being positively correlated with an increased chance of developing diabetes. Smokeless tobacco usage is identified as a significant risk factor for DM. This highlights the need to implement focused public health initiatives and policies aimed at decreasing the usage of smokeless tobacco and its influence on the incidence of diabetes. Future research should prioritize elucidating the processes behind this correlation and developing efficacious preventative methods to mitigate the worldwide burden of diabetes.

Cigarette smoking is a known risk factor for Type 2 diabetes, but evidence regarding former smoking and moist snuff (snus) use and Type 2 diabetes risk is inconclusive. This study investigated the relationships of cigarette smoking and Swedish snus use with the risk of Type 2 diabetes in a cohort of middle-aged and elderly participants.

Participants (N=36,742; age range=56-95 years) were followed for incident Type 2 diabetes and death between 2009 and 2017 through linkage to the Swedish National Patient, Prescribed Drug and Death Registers. Cox proportional hazards regression was used to obtain hazard ratios and 95% CIs adjusted for potential confounders, including physical activity, education, BMI, and alcohol intake. Analyses were conducted in 2021‒2022.

Former and current smoking was associated with an increased risk of Type 2 diabetes (hazard ratios [95% CI]=1.17 [1.07, 1.29] and 1.57 [1.36, 1.81], respectively). In those who stopped smoking, Type 2 diabetes risk remained elevated up to approximately 15 years after cessation. In participants who have never smoked, snus use was linked to a higher risk of Type 2 diabetes in the model adjusted for age and sex (hazard ratio [95% CI]=1.49 [1.04, 2.15]), but this was attenuated after multivariable adjustment (hazard ratio [95% Cl]=1.29 [0.89, 1.86]).

This study indicates that current and former smoking are associated with an increased risk of Type 2 diabetes in middle-aged and older individuals. There was less evidence of an association of snus use with the risk of Type 2 diabetes, suggesting that compounds other than nicotine may underlie the detrimental association of smoking with the risk of Type 2 diabetes.

Smoking and use of smokeless tobacco (snus) are associated with an increased risk of type 2 diabetes. We investigated whether smoking and snus use increase the risk of latent autoimmune diabetes in adults (LADA) and elucidated potential interaction with HLA high-risk genotypes.

Analyses were based on Swedish case-control data (collected 2010-2019) with incident cases of LADA (n=593) and type 2 diabetes (n=2038), and 3036 controls, and Norwegian prospective data (collected 1984-2019) with incident cases of LADA (n=245) and type 2 diabetes (n=3726) during 1,696,503 person-years of follow-up. Pooled RRs with 95% CIs were estimated for smoking, and ORs for snus use (case-control data only). The interaction was assessed by attributable proportion (AP) due to interaction. A two-sample Mendelian randomisation (MR) study on smoking and LADA/type 2 diabetes was conducted based on summary statistics from genome-wide association studies.

Smoking (RRpooled 1.30 [95% CI 1.06, 1.59] for current vs never) and snus use (OR 1.97 [95% CI 1.20, 3.24] for ≥15 box-years vs never use) were associated with an increased risk of LADA. Corresponding estimates for type 2 diabetes were 1.38 (95% CI 1.28, 1.49) and 1.92 (95% CI 1.27, 2.90), respectively. There was interaction between smoking and HLA high-risk genotypes (AP 0.27 [95% CI 0.01, 0.53]) in relation to LADA. The positive association between smoking and LADA/type 2 diabetes was confirmed by the MR study.

Our findings suggest that tobacco use increases the risk of LADA and that smoking acts synergistically with genetic susceptibility in the promotion of LADA.

Analysis codes are shared through GitHub ( https://github.com/jeseds/Smoking-use-of-smokeless-tobacco-HLA-genotypes-and-incidence-of-LADA ).

The purpose of this scoping review is to create a single narrative that describes the impact of smoking cessation on metabolic parameters in people with diabetes. It is generally well accepted that smoking enhances the harmful effects of elevated blood glucose levels, accelerating the vascular damage seen in patients with diabetes. Smoking cessation has clear benefits in terms of reducing cardiovascular morbidity and mortality. However, there is less evidence for the impact of smoking cessation on other diabetes-related complications. Studies in people with diabetes have shown improvement as well as temporary deterioration in glycemic control after ceasing smoking. Only a few studies have described the effect of quitting smoking on insulin resistance and lipid parameters, however, their results have been inconclusive. In this situation, healthcare professionals should not assume that cessation of smoking will improve metabolic parameters in patients with diabetes. It seems they should, first of all, emphasize the prevention of weight gain that may be associated with quitting smoking. The lack of data regarding the metabolic effects of smoking and smoking cessation in diabetes is very disappointing and this area needs to be addressed.

Latent autoimmune diabetes in adults (LADA) is the most common form of autoimmune diabetes diagnosed in adults. Similar to type 1 diabetes, the prevalence of LADA is impacted by ethnicity and geography. LADA is characterized by β cell loss due to autoimmunity and insulin resistance and has highly heterogeneous clinical features, autoimmunity, and genetics in a glutamic acid decarboxylase antibody (GADA) titre-dependent manner, suggesting LADA is part of a continuum spectrum between type 1 and type 2 diabetes. Although LADA is the most frequent form of autoimmune diabetes diagnosed in adults, clinical trials involving LADA are scarce. Here we review the recent advancements in LADA epidemiology, clinical features, pathogenesis, and interventions. We also highlight the environmental factors that are thought to play an important role in addition to genetics in the pathogenesis of LADA. In the future, high-throughput molecular profiles might shed light on the nature of LADA among the wide spectrum of diabetes and offer new opportunities to identify novel LADA-specific biomarkers.

Snus is an oral smokeless tobacco product which is usually placed behind the upper lip, either in a loose form or in portioned sachets, and is primarily used in Sweden and Norway. The purpose of this review is to examine the reported effects of snus use in relation to specified health effects, namely lung cancer, cardiovascular disease, pancreatic cancer, diabetes, oral cancer and non-neoplastic oral disease. The review also examines the harm reduction potential of snus as an alternative to cigarettes by comparing the prevalence of snus use and cigarette smoking, and the reported incidence of tobacco-related diseases across European Union countries. The scientific literature generally indicates that the use of snus is not a significant risk factor for developing lung cancer, cardiovascular disease, pancreatic cancer or oral cancer. Studies investigating snus use and diabetes have reported that high consumption of snus (estimated as being four or more cans per week) may be associated with a higher risk of developing diabetes or components of metabolic syndrome; however, overall results are not conclusive. Snus use is associated with the presence of non-neoplastic oral mucosal lesions which are reported to heal rapidly once use has stopped. The most recent Eurobarometer data from 2017 reported that Sweden had the lowest prevalence of daily cigarette use in the European Union at 5% whilst daily "oral tobacco" use was reported to be 20%. European data published by the World Health Organisation in 2018 indicated that Sweden had the lowest rate of tobacco-related mortality and the lowest incidence of male lung cancer. Overall, prevalence statistics and epidemiological data indicate that the use of snus confers a significant harm reduction benefit which is reflected in the comparatively low levels of tobacco-related disease in Sweden when compared with the rest of Europe. The available scientific data, including long-term population studies conducted by independent bodies, demonstrates that the health risks associated with snus are considerably lower than those associated with cigarette smoking.

The study of the sociomedical problems of diabetes mellitus led to the discovery of latent autoimmune diabetes in adults (LADA), a special form of the disease. The slow onset of the disease, the clinical signs of type 2 diabetes mellitus concurrent with the autoantibody pancreatic β-cell destruction mechanism that is characteristic of type 1 diabetes. Genetic factors play an important role in the genesis of the disease. Insulitis concurrent with intact or hypertrophic islets of the gland originally develops morphologically. Subsequently, the phenomena of islet atrophy and sclerosis are progressive. The disease is typical for young people (generally those aged 25-35 years) with normal body mass index, low blood C-peptide levels, with antibodies against β-cells, primarily to glutamate decarboxylase, being detected. Insulin preparations should be used to treat these patients.

As the heterogeneity of diabetes is becoming increasingly clear, opportunities arise for more accurate assessment of factors influencing disease onset, which may lead to more efficient primary prevention. LADA - latent autoimmune diabetes in adults - is a common, hybrid form of diabetes with features of both type 1 and type 2 diabetes. This review aims to summarize current knowledge on the pathophysiological and etiological overlap and differences between LADA and type 2 diabetes, discuss similarities between LADA and type 1 diabetes and point at future research needs. Studies conducted to date show a clear genetic overlap between LADA and type 1 diabetes with a high risk conferred by variants in the human leukocyte antigen (HLA) region. In contrast, data from the limited number of studies on lifestyle factors available indicate that LADA may share several environmental risk factors with type 2 diabetes including overweight, physical inactivity, alcohol consumption (protective) and smoking. These factors are known to influence insulin sensitivity, suggesting that insulin resistance, in addition to insulin deficiency due to autoimmune destruction of the beta cells, may play a key role in the pathogenesis of LADA. Moreover, this implies that onset of LADA, similar to type 2 diabetes, to some extent could be prevented or postponed by lifestyle modification such as weight reduction and increased physical activity. The preventive potential of LADA is an important topic to elucidate in future studies, preferably intervention studies.

In order to prevent diabetes it is important to identify common, modifiable risk factors in the population. Such knowledge is extensive for type 2 diabetes but limited for autoimmune forms of diabetes.

This review aims at summarizing the limited literature on potential environmental (lifestyle) risk factors for LADA.

A PubMed search identified 15 papers estimating the risk of LADA in relation to lifestyle. These were based on data from two population-based studies; one Swedish case-control study and one Norwegian cohort study.

Studies published to date indicate that the risk of LADA is associated with factors promoting insulin resistance and type 2 diabetes such as overweight, physical inactivity, smoking, low birth weight, sweetened beverage intake and moderate alcohol consumption (protective). Findings also indicate potential effects on autoimmunity exerted by intake of coffee (harmful) and fatty fish (protective). This supports the concept of LADA as being a hybrid form of diabetes with an etiology including factors associated with both insulin resistance and autoimmunity.

LADA may in part be preventable through the same lifestyle modifications as type 2 diabetes including weight loss, physical activity and smoking cessation. However, current knowledge is hampered by the small number of studies and the fact that they exclusively are based on Scandinavian populations. There is a great need for additional studies exploring the role of lifestyle factors in the development of LADA.

A recent meta-analysis reported smoking to be associated with a 37% higher risk of type 2 diabetes in current smokers, rising to a 57% increase in heavy smokers, which declines on quitting. If the increase results from nicotine exposure, it is possible that using Swedish moist snuff ("snus"), which provides at least equivalent nicotine doses, might also increase diabetes risk. Following a recent publication reporting pooled results from five cohorts, we present a detailed meta-analysis of data from 18 studies. Based on covariate-adjusted estimates, no significant increased risk was seen in never smokers with RRs (95% CIs) of 1.08 (0.86-1.34), 0.93 (0.79-1.11) and 1.05 (0.94-1.18) for current, former and ever snus users. Significant increases were also not seen in the whole population, the corresponding RR estimates being 1.18 (0.94-1.48), 0.69 (0.49-0.96) and 0.95 (0.81-1.11). Nor was there an association of snus use with related endpoints, such as impaired glucose tolerance. However, dose-response analyses showed a relationship, with the highest levels of snus exposure associated with a diabetes RR of 1.65 (1.25-2.18) in never smokers. The evidence relating snus to type 2 diabetes is somewhat limited, requiring further studies to confirm any possible relationship.

Smoking and nicotine exposure increase insulin resistance and the risk of type 2 diabetes. Swedish smokeless tobacco (snus) is high in nicotine, and its use is prevalent in Scandinavian countries, but few studies have investigated snus use in relation to diabetes risk.

To explore the association between snus use and risk of type 2 diabetes using pooled data from five cohorts.

Analyses were based on prospective studies conducted between 1990 and 2013 including 54 531 never-smoking men and 2441 incident cases of type 2 diabetes identified through screening, self-reporting and hospital and prescription registries. Hazard ratios (HRs) and 95% confidence intervals (CIs) were assessed and adjusted for age, body mass index, educational level, alcohol consumption and physical activity.

Compared to never users, the HR of type 2 diabetes was 1.15 (95% CI: 1.00-1.32) in current users of snus. In individuals consuming 5-6 boxes per week, the HR was 1.42 (95% CI: 1.07-1.87); in those consuming ≥7 boxes per week, the HR was 1.68 (95% CI: 1.17-2.41). Each additional box of snus consumed per week yielded an HR of 1.08 (95% CI: 1.01-1.16).

Our findings indicate that high consumption of snus is a risk factor for type 2 diabetes. The risk was similar to that in smokers, implying that smokers will not reduce their risk of type 2 diabetes by changing to snus use. The results also support the notion that nicotine increases the risk of type 2 diabetes.