A recent study has shown that exposure to secondhand smoke may increase the risk of obesity and type 2 diabetes in adults.

The study, which involved over 6,300 adults who took part in the US National Health and Nutrition Examination Survey, found that those exposed to secondhand smoke had heavier weights and higher rate of type 2 diabetes than nonsmokers.

The American researchers from Charles R. Drew University also found that compared to nonsmokers, people exposed to secondhand smoke had a higher level of insulin resistance that could cause type 2 diabetes, higher levels of fasting blood sugar, and a higher hemoglobin A1c.

Meanwhile, both smokers and people exposed to secondhand smoke had similar diabetes rates, and that the two groups had a higher hemoglobin A1c than those people who do not smoke.

The study was presented at the Endocrine Society's annual meeting in Houston, Texas on Sunday.

While the researchers found a link between secondhand smoke and increased risk of obesity and type 2 diabetes, they did not confirm a cause-and-effect relationship.

"The association between secondhand smoke and type 2 diabetes was not due to obesity," Dr Theodore Friedman, the co-author of the study, said in an Endocrine Society news release.

"More studies are needed to show whether secondhand smoke is a cause of diabetes. More effort needs to be made to reduce exposure of individuals to secondhand smoke,” he added. (Press TV)