Smoking Raises Risk for All Type-2 Diabetes Subtypes, Especially Severe Ones: Study - Video

A recent large Scandinavian study, presented at the European Association for the Study of Diabetes (EASD) in 2025, and published in the journal Diabetologia, revealed that smoking—whether current or past—increases the risk of developing all four major subtypes of type-2 diabetes (T2D). This finding is especially important for countries like India, which face a growing diabetes burden and high tobacco use in various forms, including cigarettes, bidis, and smokeless products.

Type-2 diabetes affects over 100 million people in India, often developing early due to a mix of genetics, diet, obesity, and sedentary lifestyles. Importantly, diabetes isn't a single disease but comprises several subtypes varying in severity, speed of complications, and treatment responses.

The study analyzed 3,325 patients from Sweden and Norway, categorizing them into four subtypes: severe insulin-resistant diabetes (SIRD), severe insulin-deficient diabetes (SIDD), mild obesity-related diabetes (MOD), and mild age-related diabetes (MARD). Smokers faced significantly heightened risks across all subtypes, especially a more than two-fold increase for the severe insulin-resistant group.

The findings are even more alarming for heavy smokers, who face up to 2.35 times higher risk of SIRD, and 45-57% greater risk for other subtypes. Genetic predisposition further magnifies these dangers, creating a deadly synergy with tobacco use. The study also found that smokeless tobacco users had higher diabetes risks—a critical insight for regions like India where smokeless tobacco use is widespread.

These results send an urgent message: smoking is a powerful accelerator of diabetes, not just a cause of cancer and heart disease. Quitting smoking is paramount to preventing and managing diabetes, especially in genetically vulnerable populations. Effective tobacco control and early screening are essential tools in fighting the growing diabetes epidemic worldwide.

Reference: Jessica Edstorp, Yuxia Wei, Emma Ahlqvist, Lars Alfredsson, Valdemar Grill, Leif Groop, Bahareh Rasouli, Elin P. Sørgjerd, Per M. Thorsby, Tiinamaija Tuomi, Bjørn O. Åsvold & Sofia Carlsson; Smoking, use of smokeless tobacco, HLA genotypes and incidence of latent autoimmune diabetes in adults; Diabetologia; https://doi.org/10.1007/s00125-022-05763-w