Weight gain after stopping smoking is associated with an increased short-term risk of type 2 diabetes (T2D), according to new research published in the New England Journal of Medicine.
The authors, led by Geng Zong, PhD, of the T.H. Chan School of Public Health at Harvard University, reviewed three cohort studies that involved men and women in the U.S., who had reported quitting smoking. They assessed if smoking cessation and changes in body weight impacted the risk of developing T2D, death from cardiovascular disease (CVD) and all-cause mortality.
“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 senior author Qi Sun, of Harvard University in a prepared statement. “But our study shows that it is 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.”
The final cohort included 162,807 and 170,723 individuals for the diabetes and mortality analyses, respectively.
After an average follow-up of almost 20 years, Zong and colleagues found the risk of T2D was 22 percent higher among individuals who had quit two to six years before. However, the risk peaked 5 to 7 years after cessation occurred and then gradually decreased—this was a pattern seen in all weight groups.
Unsurprisingly, the temporary increase in the risk of T2D was directly proportional to weight gain and the risk was not increased among quitters without weight gain. Compared to current smokers:
- Recent quitters without weight gain had an 8 percent increase in T2D risk.
- Quitters who gained less than 11 pounds (5 kg) had a 15 percent increase in T2D risk.
- Quitters who gained 11.1 to 22 pounds (5.1 to 10 kg) had a 36 percent increase in T2D risk.
- Quitters who gain more than 22 pounds (10 kg) had a 59 percent increase in T2D risk.
Quitters, the researchers wrote, did not have a temporary increase in mortality, regardless of weight changes after cessation. Compared to current smokers, those who gained more than 22 pounds (10kg) had a 50 percent decrease in risk for early death due to any cause and a 67 percent decrease in risk for CVD death.
“Smokers shouldn’t be deterred by potential weight gain after quitting because the short-term and long-term reduction of cardiovascular disease risk is clear,” said lead author Yang Hu, of the Departments of Nutrition and Epidemiology at Harvard University in a prepared statement issued by Harvard University. “However, quitters may want to consider eating a healthful diet and engaging in physical activities to minimize weight gain to keep their diabetes risk at bay and to maximize the health benefits of quitting.”
As a senior news writer for TriMed, Subrata covers cardiology, clinical innovation and healthcare business. She has a master’s degree in communication management and 12 years of experience in journalism and public relations.