Dear Mayo Clinic: Does smoking have an effect on diabetes?
Answer: Yes. There is some evidence that cigarette smoking can raise the risk of developing diabetes. And for those who have diabetes, smoking can increase the number of complications from the disease, as well as the severity of those complications.
Someone who has diabetes has too much blood sugar (commonly called blood glucose), which can lead to serious health concerns, such as cardiovascular disease, nerve damage (neuropathy), kidney damage, problems with the eyes and feet, bone and joint disorders, and skin problems.
Smoking may increase the risk of diabetes because it can increase blood sugar levels. It also affects the body's ability to respond to its own insulin — a hormone whose main job is to keep the level of sugar in the bloodstream within a normal range. Eventually, smoking may lead to insulin resistance. Thus, the more a person smokes, the greater the risk of diabetes. Heavy smokers — more than 20 cigarettes a day — almost double their risk of developing diabetes, when compared with nonsmokers.