Current smokers and people regularly exposed to second-hand smoke have a significantly increased risk for type 2 diabetes compared with people who have never smoked, according to a new meta-analysis conducted by researchers from Harvard T.H. Chan School of Public Health, Huazhong University of Science and Technology, Wuhan, China, and National University of Singapore. The researchers estimated that 11.7% of cases of type 2 diabetes in men and 2.4% in women (about 27.8 million cases in total worldwide) may be attributable to active smoking. They also found that risk decreases as time elapses after smokers quit.
“Cigarette smoking should be considered as a key modifiable risk factor for diabetes. Public health efforts to reduce smoking will have a substantial impact on the global burden of type 2 diabetes,” said co-author Frank Hu, professor of nutrition and epidemiology.
The study will be published September 18, 2015 in The Lancet Diabetes & Endocrinology.
While the evidence pointing to smoking as a risk factor for cancer, respiratory diseases, and cardiovascular disease is overwhelming, corroboration of a link between smoking and type 2 diabetes risk has been slower to build. In 2014, the U.S. Surgeon General’s report for the first time included a section on smoking and diabetes risk and argued for the causal relation between them, although it did not discuss the relation of passive smoking and smoking cessation with diabetes risk.