Mom's Prenatal Smoking Linked to Kid's Obesity
Smoking while pregnant may raise a baby's risk factor for teen obesity by impacting the brain's reward system.
Many people smoke in order to keep their weight down, but a new study shows that doing so during pregnancy can actually cause an increased risk of obesity in their children. In the study, Zdenka Pausova, MD of the Hospital for Sick Children in Toronto and her colleagues interviewed 379 teens between the ages of 13-19, 180 of whom had been exposed to prenatal maternal smoking that amounted to 11 cigarettes per day on average during all three trimesters. The findings showed that children whose mothers smoked during pregnancy had a higher body fat percentage and fat intake in adolescence than the offspring of nonsmokers. "Prenatal exposure to maternal cigarette smoking is a well-established risk factor for obesity, but the underlying mechanisms are not known," wrote Pausova. It appears that part of this switch in genetics may have to do with subtle changes in the brain's reward mechanisms. Offspring of smokers had an overall lower volume in the amygdala, which is part of the brain's reward processing system, which means the prenatal exposure to smoking might promote obesity by enhancing dietary preferences for fatty foods.