WASHINGTON, July 3 (Xinhua) -- Older women who quit smoking could reduce their risk of heart disease, regardless of whether they have diabetes, a U.S. study said Wednesday.
Researchers from the Indiana University also cautioned in the Journal of the American Medical Association that women should guard against too much weight gain that may lead to diabetes after quitting smoking.
The study found that women who gained more than 5 kilograms after they quit smoking still saw their risk for cardiovascular disease drop, but their risk didn't drop as much as for those who gained less than the amount.
The researchers analyzed data for 104,391 postmenopausal women aged 50 to 79 who took part in the U.S. government-funded Women's Health Initiative.
Among women without diabetes, those who quit smoking within the past three years had a 26 percent lower risk of developing heart disease compared with those who continued smoking. Those who had quit smoking for more than three years had a 61 percent lower risk, said the study.
Among women with diabetes, those who quit smoking had about a 60 percent lower risk for heart disease, regardless of how recently they had quit, it said.
The majority of women in the study gained less than 5 kilograms after they quit smoking, but for the smaller number of women who gained more than 5 kilograms, there was less heart health benefit from stopping smoking, especially for women with diabetes.
"Our study found that if you quit smoking, even for older women, the benefits start pretty quickly, within years," lead author Juhua Luo, an assistant professor at the Indiana University School of Public Health, said in a statement. "It's never too late to benefit from quitting smoking."