Smokers stay thin because their addiction helps dislodge stored body fat, a new study has found.
Even if they eat less than usual, people trying to quit smoking can gain an average of eight to 10 pounds, said Marc K. Hellerstein, a University of California at Berkeley professor and lead author of the study.But researchers warned that smoking should not be used as a diet aid.
"Smoking, from a health point of view, is much more risky than weighing those extra few pounds," Hellerstein said.
The study published Thursday was the first to show that smoking stimulates a process called lipolysis, which frees lipids, or fats, from cells and spills them into the bloodstream.
Previous studies have shown that smoking increases a person's metabolism, the process that turns the calories in food into energy.
The new study was the first to show that smoking directly stimulates a process called lipolysis that frees lipids, or fats, from cells and spills them into the bloodstream.
Cholesterol levels increase after a person smokes a cigarette and the ratio between so-called good and bad cholesterols tips toward the kind associated with heart disease.
"It's one reason why smokers, over time, would have heart disease and arteriosclerosis: their cholesterol is worse," Hellerstein said.
According to the study, a person can burn about 200 calories a day through moderate smoking.