There’s no question about it—smoking is linked to a long laundry list of health problems, including cancer and cardiovascular disease. Unfortunately, quitting is often accompanied by weight gain. While not everyone who quits will gain weight, a number of studies have linked the two together. It is estimated that smoking cessation is associated with an average weight gain of about 10 pounds, with most of the weight gain occurring within three months of quitting.
What Does Research Show?
A new study has found that the risk of developing type 2 diabetes may also increase after a person quits smoking. Investigators found that the risk of type 2 diabetes was higher among those who had recently stopped smoking (within 2 to 6 years of smoking cessation) as compared to individuals who were still using tobacco. The increased risk in developing diabetes was directly related to weight gain, as an additional risk was not observed in those who quit but didn’t gain weight.
Previous studies have reported a link between the onset of type 2 diabetes and recent smoking cessation, but the reasons for the increased risk weren’t clear. These new findings provide an opportunity to discuss the risks of smoking, weight gain, and diabetes with patients seeking to make behavior changes.
“It’s been known that quitters may have an elevated risk of developing diabetes or worsening glucose tolerance in the first few years after quitting, and this may discourage smokers from quitting,” said Qi Sun, associate professor in the department of nutrition at Harvard University and senior author of the study.
However, the good news is that the risk for diabetes is related to the amount of weight gained and may not be permanent. Sun pointed out that in their study, the “weight change after quitting that determines diabetes risk–so as long as quitters minimize their weight gain, their diabetes risk will not increase and, over the long run, is reduced.”
In this study, the goal was to investigate if weight gain after smoking cessation affected the health benefits of smoking cessation. They identified individuals who had quit smoking and looked at associations between their weight gain and the risk of not only developing type 2 diabetes, but its impact on risk of death due to cardiovascular disease and other conditions. Their cohort was comprised of 171,150 U.S. men and women who were enrolled in three large studies–the Nurses’ Health Study, the Nurses’ Health Study II, and the Health Professionals Follow-Up Study—with nearly 19 years of data.
Individuals who had recently quit smoking had, on average, a 22% higher risk of developing type 2 diabetes when compared with people who continued to smoke. The increased risk, however, peaked at 5-7 years after they quit smoking and then gradually declined. There was no increased risk among those who did not gain weight after quitting, and in the longer term, smoking cessation was associated with a decrease in the risk of diabetes. By 30 years, the risk of developing diabetes was similar to that of persons who had never smoked.
What Can Healthcare Providers Do?
An important finding was that even with weight gain, the benefits of smoking cessation outweighed any potential risk of diabetes. The risk of cardiovascular mortality decreased substantially after smoking cessation in all weight-change groups, even among those who gained 20 or more pounds. The risk of early death due to all causes or from cardiovascular disease decreased, on average, by 50% and 67%, after a person stopped smoking.
For nurses discussing smoking cessation with patients, it should be emphasized that they shouldn’t be discouraged from quitting because of potential weight gain. The benefits of quitting should be emphasized, especially in terms of a short-term and long-term reduction of cardiovascular disease risk and early death. Discussions on eating a healthy diet and engaging in physical activity to stave off weight gain and diabetes risk will also be beneficial to those considering quitting.
Last updated on 9/26/19.