Nov. 16, 2010 (Chicago) -- Smokers who kick the habit may improve their levels of "good" HDL cholesterol within one year, a study of nearly 1,000 people suggests.
People who quit smoking gained about 10 pounds over a one-year period, while those who continued to light up put on about 1 1/2 pounds, the study showed.
Using nuclear magnetic resonance spectroscopy imaging, the researchers found that the actual number of HDL particles also increased in people who quit, compared with those who continued smoking.
HDL Improvements May Lower Heart Risks
AHA spokesman Russell Luepker, MD, of the University of Minnesota School of Public Health, tells WebMD that studies have suggested that weight gain may have more of a negative effect on LDL levels than on HDL levels.
"If people hadn't gained weight, there might have been an LDL benefit [associated with quitting smoking] and an even more robust benefit in terms of HDL," says Luepker, who was not involved with the work.
Over time, the improvements in HDL would probably translate into a lower risk of cardiovascular disease, Gepner tells WebMD. Studies have shown that every 1 mg/dL increase in HDL lowers the risk of cardiovascular disease events, including heart attacks, strokes, and death from heart disease, by 2% to 3% over 10 years, he says.
Interestingly, heavy smokers and light smokers gained the same HDL benefit, Gepner says. The type of smoking cessation strategy also did not affect the results.
The study involved 923 men and women enrolled in a study testing various smoking cessation methods, including nicotine lozenges and nicotine patches. When they entered the study, participants smoked an average of about two packs a day. By one year later, about one-third had successfully kicked the habit.
Gepner says exactly how smoking affects cholesterol levels is unknown, although it is believed to have to do with transporting lipid particles.
This study was presented at a medical conference. The findings should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.