Smoking and diabetes: why should we be concerned?

Few people are aware of the close links between smoking and diabetes. Yet, these links are well established by research. Diabetes is a metabolic disease characterized by chronic hyperglycemia, due to insulin resistance variably associated with impaired insulin secretion. In France, more than 4 million people live with diabetes, representing nearly 6.5% of the population.[1]. This condition exposes patients to cardiovascular, renal, neurological, ophthalmological, and oral complications. Scientific studies[2] show that smoking is the leading cause of death from all causes in people with diabetes [3]. It worsens complications related to diabetic disease and impairs glycemic control.

Despite this finding, nearly 410,000 people living with diabetes continue to use tobacco: approximately a quarter of people living with type 1 diabetes (T1D) and nearly 13% of people with type 2 diabetes (T2D), according to data from Public Health France.[4]. For comparison, the prevalence of daily smoking in the general adult population is 18.2%.[5]. Furthermore, smoking is a risk factor for developing type 2 or gestational diabetes. By promoting metabolic imbalances, tobacco increases the chances of developing this condition in individuals who smoke or are excessively exposed to it.

Smoking: a risk factor for type 2 diabetes

Smoking (active or passive) is recognized as a major risk factor for the development of type 2 diabetes, but also for prediabetes and gestational diabetes.[6]. In the case of diabetes, there is a dose-response effect, meaning that the more cigarettes smoked, the more complications increase and worsen. Tobacco smoke contains more than 7,000 chemical substances, including nicotine, heavy metals, and toxic compounds.[7]. The substances present in a cigarette are not limited to the lungs: they circulate throughout the body and disrupt its functions. These substances have direct and indirect effects on carbohydrate metabolism.

Explanation of the metabolic effects of smoking:

Smoking causes damage to the pancreatic beta cells responsible for insulin production.[8]. Indeed, the presence of nicotine reduces the mass and function of these cells, thus disrupting glucose regulation.[9] and therefore playing an important role in the development of type 2 diabetes.

Smoking also causes low-grade inflammation that disrupts insulin signaling in cells, reducing their ability to absorb glucose.

Furthermore, tobacco smoke creates oxidative stress[10], This refers to damage caused by aggressive molecules that harm cells and tissues and impair the function of insulin receptors. Studies have shown that acute impairment of glucose tolerance and increased insulin resistance can occur after smoking just three cigarettes, even in non-smokers.[11]. Carbon monoxide, one of the toxic components of tobacco smoke, also affects the inner lining of blood vessels called the endothelium, making them less efficient at transporting oxygen and nutrients, thus exacerbating metabolic disorders. Smoking promotes the accumulation of abdominal fat, increases the secretion of free fatty acids and inflammatory cytokines, and disrupts hormonal balance, thereby increasing the risk of metabolic syndrome.[12]. All of this contributes to what is called insulin resistance, a condition where the body no longer responds properly to insulin, promoting the development of type 2 diabetes.[13]. Thus, active smoking, and to a lesser extent passive smoking, increases the risk of developing type 2 diabetes by 30 to 40 times compared to non-smokers.[14], Smoking cessation increases the risk of developing prediabetes and presents an additional risk. Quitting smoking reduces this risk and improves the management of this chronic disease.[15]. After twelve to thirty years of abstinence, the risk of diabetes becomes comparable to that of people who have never smoked.[16].

In pregnant women, smoking increases the risk of gestational diabetes and obstetric complications. It is also associated with low birth weight and is a risk factor for type 2 diabetes in adulthood for the child.[17].

The impact of tobacco on glycemic control and complications in a smoker living with diabetes.

The effects of tobacco are also highly detrimental to people already living with diabetes, since it directly influences blood glucose regulation and insulin function, while also worsening complications related to the disease.

The effects of smoking on blood sugar and insulin

In people with diabetes, smoking disrupts blood sugar balance. Nicotine, as well as numerous other toxic substances present in smoke (heavy metals, chemical compounds), play a role in these mechanisms.[18]. For example, nicotine stimulates the production of hyperglycemic hormones called catecholamines (including adrenaline), which increase blood glucose levels, heart rate, and blood pressure. These hormones disrupt both insulin secretion and glucose transport to cells, exacerbating metabolic imbalances.[19]. The same mechanisms are then at play, leading to insulin resistance.[20], than in a non-diabetic smoker. But in a person living with diabetes, all these fluctuations make diabetes control more complex and increase the risk of major complications of the disease.

The impact of smoking on diabetes complications

In smokers with diabetes, smoking exacerbates several major complications of diabetes.

• Diabetic nephropathy is a serious complication and a major cause of end-stage renal disease. Smoking is an independent factor in the onset and progression of kidney damage, which can lead to end-stage renal disease.[22].
• Diabetic neuropathy is a complication that occurs when chronic high blood sugar damages the nerves and disrupts their function. Smoking has been shown to damage nerves and blood circulation, leading to pain, sensory disturbances, and an increased risk of foot ulcers.[23], infections, and in the most serious cases, amputations[24].
• Diabetic retinopathy: smoking damages the blood vessels of the retina, contributing to vision loss[25].
• Macrovascular complications (which affect large blood vessels)
• The risk of cardiovascular disease, already high in people with diabetes, is considerably amplified by tobacco use.[26]: smoking increases the risk of myocardial infarction by 51 %, the risk of stroke by 54 % and the risk of peripheral arterial disease by 115 %.

• Circulatory disorders and wound healing: the combination of tobacco and diabetes slows down wound healing and increases the risk of infection.
• Oral health: Tobacco and diabetes weaken the gums and delay healing after dental treatment. Tobacco use in people with diabetes is associated with an increased risk of developing and progressing periodontal disease (disease of the deep tissues that support the teeth).
• Cancers: Type 2 diabetes increases the risk of cancer from all causes by at least 60%, particularly pancreatic, liver and colorectal cancer.

Smoking cessation: the benefits for people living with diabetes

Quitting smoking offers significant benefits for people with diabetes, despite some temporary effects. Smoking cessation is also associated with a reduced risk of cardiovascular disease, microvascular complications, and all-cause mortality in smokers with diabetes, even in cases of short-term weight gain.[27].

This weight gain[28], This can be explained by the decrease in basal metabolism and the increase in appetite linked to the disappearance of nicotine's anorexigenic effect. It can also be exacerbated by confusion between the sensation of withdrawal and hunger, leading to compensatory eating. In some patients (13 %), it can reach 10 kg, while others (16 %) do not gain weight, or even lose weight when they receive appropriate support.[29].

In people living with diabetes, blood sugar imbalances may occur in the months following cessation, but this is offset by a gradual improvement in insulin sensitivity. After about three years, blood sugar levels normalize and become similar to those of non-smokers.[30]. Cardiovascular benefits, meanwhile, are observed rapidly after weaning, even in cases of weight fluctuation.[31].

To optimize these results, nutritional guidance and the prescription of nicotine replacement therapies at the correct dosage by trained healthcare professionals are essential. Recommendations from learned societies such as the French-Speaking Society of Tobacco Studies (SFT) and the French-Speaking Society of Diabetes (SFD) emphasize the importance of adjusting carbohydrate intake to maintain satiety and avoid snacking.[32], This can be combined with physical activity and cognitive behavioral therapy. In patients with type 1 diabetes, it is possible to adjust the doses of rapid-acting insulin according to the amount of carbohydrates consumed.[33]. Individuals trained in functional insulin therapy will find it easier to make these adjustments. Dietary support therefore plays a key role, not only in limiting weight gain, but also in stabilizing blood sugar levels and supporting the patient throughout their withdrawal process.

And what about new tobacco products?

New tobacco products, often perceived as less harmful, are not without risks for people living with diabetes. Available data, although limited, indicate that the use of electronic cigarettes (vapes) may be associated with increased glucose intolerance and a higher risk of developing type 2 diabetes.[34]. Heated tobacco products, which are experiencing rapid growth, also appear to increase this risk, according to initial studies.[35]. This data will need to be confirmed.

Ultimately, smoking and diabetes are closely linked, exacerbating health risks. Smoking not only increases the likelihood of developing type 2 diabetes but also complicates its management for people living with all types of diabetes, accelerating the onset of serious complications. Smoking cessation, despite some temporary effects such as weight gain, remains essential for reducing these risks and improving patients' quality of life. Data regarding vaping and heated tobacco products are still limited and require further confirmation.

©Generation Without Tobacco

Author: Noémie Bouchard - French Federation of Diabetics

[1] Data.ameli.fr (2023). Available on https://data.ameli.fr/pages/pathologies/?refine.patho_niv1=Diab%C3%A8te

[2] DURLACH, Vincent, VERGÈS, B., AL-SALAMEH, A., et al. Smoking and diabetes interplay: a comprehensive review and joint statement. Diabetes & Metabolism, 2022, vol. 48, no. 6, art. 101370. Available at: https://pubmed.ncbi.nlm.nih.gov/35779852/

[3] TISSOT, Catherine, and NIKPEYMA, Atefeh. Smoking and diabetes: a risk to consider and a major dietary challenge. Dietary Information, 2025, no. 2, pp. 15-21.

[4] FOSSE-EDORH, Sandrine, PIFFARETTI, Cécile, SABONI, Lucile, et al. Entred studies: a system to improve knowledge of the health status of people with diabetes in France – First results of the third edition conducted in metropolitan France in 2019. Weekly Epidemiological Bulletin, 2022, no. 22, pp. 384-391. Available at https://beh.santepubliquefrance.fr/beh/2022/22/2022_22_1.html

[5] Sharp decline in smoking in FranceIn 10 years, 4 million fewer daily smokers. https://www.santepubliquefrance.fr/presse/2025/forte-baisse-du-tabagisme-en-france-en-10-ans-4-millions-de-fumeurs-quotidiens-en-moins . Accessed March 17, 2026.

[6] DURLACH, Vincent, VERGÈS, Bruno, AL-SALAMEH, Abdallah, et al. Smoking and diabetes: time for action. Weekly Epidemiological Bulletin, November 8, 2022, No. 22, pp. 392–398. Available at: https://beh.santepubliquefrance.fr/beh/2022/22/pdf/2022_22_2.pdf

[7] World Health Organization, 2025. Summary of knowledge about tobacco. Geneva: World Health Organization. Available at: https://www.who.int/fr/publications/b/80110

[8] SUN, Lingli, WANG, Xiaohua, GU, Tianye, HU, Baoying, LUO, Jiashan, QIN, Yi, and al. Nicotine triggers islet β cell senescence to facilitate the progression of type 2 diabetes. Toxicology, 2020, vol. 441, art. 152502. Available at: https://pubmed.ncbi.nlm.nih.gov/32473187/

[9] TONG, Xin, CHAUDHRY, Zunaira Z., LEE, Chih-Chun CC, BONE, Robert NRN, KANOJIA, Sukrati, MADDATU, Judith J., et al. Cigarette smoke exposure impairs β-cell function through activation of oxidative stress and ceramide accumulation. Molecular Metabolism, 2020, vol. 37, art. 100975. Available at: https://pubmed.ncbi.nlm.nih.gov/32283079/

[10] Li, Z., Xu, W., Su, Y., Gao, K., Chen, Y., Ma, L. & Xie, Y., 2019. Nicotine induces insulin resistance via downregulation of Nrf2 in cardiomyocyte. Molecular and Cellular Endocrinology, 495, p.110507. Available at: https://pubmed.ncbi.nlm.nih.gov/31315024/

[11] Artese, A., Stamford, BA & Moffatt, RJ, 2017. Cigarette smoking: an accessory to the development of insulin resistance. American Journal of Lifestyle Medicine, 13(6), pp.602–605. Available at: https://pubmed.ncbi.nlm.nih.gov/31662726/

[12] THUILLIER, P., and MANSOURATI, J. What are the links between smoking and insulin resistance, insulin sensitivity? Metabolic Disease Medicine, 2023, vol. (number not specified), art. S1957255723000202. Available at: https://www.sciencedirect.com/science/article/abs/pii/S1957255723000202

[13] DURLACH, Vincent, VERGÈS, Bruno, AL-SALAMEH, Abdallah, et al. Smoking and diabetes: time for action. Weekly Epidemiological Bulletin, November 8, 2022, No. 22, pp. 392–398. Available at: https://beh.santepubliquefrance.fr/beh/2022/22/pdf/2022_22_2.pdf

[14] US Department of Health and Human Services. The Health Consequences of Smoking — 50 Years of Progress: A Report of the Surgeon General. Atlanta (GA): Centers for Disease Control and Prevention (US), National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2014. Available at: https://www.ncbi.nlm.nih.gov/books/NBK179276/

[15] World Health Organization, 2025. Summary of knowledge about tobacco. Geneva: World Health Organization. Available at: https://www.who.int/fr/publications/b/80110

[16] Hu, Y., Zong, G., Liu, G., et al., 2018. Smoking cessation, weight change, type 2 diabetes, and mortality. The New England Journal of Medicine, 379(7), pp.623–632. Available at: https://www.nejm.org/doi/full/10.1056/NEJMoa1803626

[17] Ravelli, AC, van der Meulen, JH, Osmond, C., Barker, DJ & Bleker, OP, 1999. Obesity at the age of 50 in men and women exposed to famine prenatally. American Journal of Clinical Nutrition, 70(5), pp.811–816. Available at: https://pubmed.ncbi.nlm.nih.gov/10539740/

[18] DURLACH, Vincent, VERGÈS, Bruno, AL-SALAMEH, Abdallah, et al. Smoking and diabetes: time for action. Weekly Epidemiological Bulletin, November 8, 2022, No. 22, pp. 392–398. Available at: https://beh.santepubliquefrance.fr/beh/2022/22/pdf/2022_22_2.pdf

[19] DURLACH, Vincent, VERGÈS, Bruno, AL-SALAMEH, Abdallah, et al. Smoking and diabetes: time for action. Weekly Epidemiological Bulletin, November 8, 2022, No. 22, pp. 392–398. Available at: https://beh.santepubliquefrance.fr/beh/2022/22/pdf/2022_22_2.pdf

[20] THUILLIER, P., and MANSOURATI, J. What are the links between smoking and insulin resistance, insulin sensitivity? Metabolic Disease Medicine, 2023, vol. (number not specified), art. S1957255723000202. Available at: https://www.sciencedirect.com/science/article/abs/pii/S1957255723000202

[21] US Department of Health and Human Services. The Health Consequences of Smoking — 50 Years of Progress: A Report of the Surgeon General. Atlanta (GA): Centers for Disease Control and Prevention (US), National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2014. Available at: https://www.ncbi.nlm.nih.gov/books/NBK179276/

[22] Clair, C., Cohen, M. J., Eichler, F., Selby, K. J. & Rigotti, N. A., 2015. The effect of cigarette smoking on diabetic peripheral neuropathy: a systematic review and meta-analysis. Journal of General Internal Medicine, 30(8), pp.1193–1203. Available at: https://pubmed.ncbi.nlm.nih.gov/25947882/

[23] Chakkarwar, VA, 2012. Smoking in diabetic nephropathy: sparks in the fuel tank? World Journal of Diabetes, 3(12), pp.186–195. Available at: https://pubmed.ncbi.nlm.nih.gov/23301120/

[24] Xia, N., Morteza, A., Yang, F., Cao, H. & Wang, A., 2019. Review of the role of cigarette smoking in diabetic foot. Journal of Diabetes Investigation, 10(2), pp.202–215. Available at: https://pubmed.ncbi.nlm.nih.gov/30300476/

[25] St Claire S, Aarsand R, Cui M, Tursan d'Espaignet E, Mueller A, Fayokun R et al. WHO tobacco knowledge summaries: tobacco and vision loss. Geneva: World Health Organization; 2022. Available on: https://www.drugsandalcohol.ie/37965/1/WHO_Tobacco_and_vision_loss.pdf

[26] World Health Organization, 2025. Summary of knowledge about tobacco. Geneva: World Health Organization. Available at: https://www.who.int/fr/publications/b/80110

[27] Sun, Q., Liu, G., Willett, WC, et al., 2020. Smoking cessation and weight change in relation to cardiovascular disease and mortality among adults with type 2 diabetes mellitus. Lancet Diabetes & Endocrinology, 8(8), pp.649–659. Available at: https://pubmed.ncbi.nlm.nih.gov/31924561/

[28] After 1 year of abstinence and usually within the first 6 months

[29] Aubin, HJ, Farley, A., Lycett, D., Lahmek, P. & Aveyard, P., 2012. Weight gain in smokers after quitting cigarettes: meta‑analysis. BMJ, 345, p.e4439. Available at: https://www.bmj.com/content/345/bmj.e4439

[30] Tramunt, B. & Durlach, V., 2023. Smoking cessation and diabetes: what benefits for what risks? Metabolic Disease Medicine, 17(2), pp.125–131. Available at: https://www.researchgate.net/publication/368480646_Sevrage_tabagique_et_diabete_quels_benefices_pour_quels_risques

[31] Clair, C., Rigotti, N. A., Porneala, B., Fox, C. S., D'Agostino, R. B., Pencina, M. J. & Meigs, J. B., 2013. Association of smoking cessation and weight change with cardiovascular disease among adults with and without diabetes. JAMA, 309(10), pp.1014–1021. Available at: https://pubmed.ncbi.nlm.nih.gov/23483176/

[32] TISSOT, Catherine, and NIKPEYMA, Atefeh. Smoking and diabetes: a risk to consider and a major dietary challenge. Dietary Information, 2025, no. 2, pp. 15-21.

[33] IBIDEM

[34] Sivandzade, F. & Cucullo, L., 2019. Assessing the protective effect of rosiglitazone against electronic cigarette/tobacco smoke‑induced blood–brain barrier impairment. BMC Neuroscience, 20, article 15. Available at: https://pmc.ncbi.nlm.nih.gov/articles/PMC6449906/

[35] Kim, D., Choy, YS & Park, E.‑C., 2017. Association between secondhand smoke and glycemic control in adult diabetes patients. Preventive Medicine, 94, pp. 48–54. Available at: https://pubmed.ncbi.nlm.nih.gov/27856339/

French Federation of Diabetics