Scientists Find Connection Between Nicotine, Weight It helps tells the brain to stop eating By Matt Cantor, Newser User Posted Jun 10, 2011 4:38 PM CDT 10 comments Comments Scientists say they've figured out why those who quit smoking often gain weight. (Shutterstock) (Newser) – For some smokers, the threat of weight gain is a deterrent to quitting—and now, scientists think have finally discovered the link between the two. Nicotine binds to receptors on brain cells, including those in the hypothalamus that tell your body when your belly is full, reports AP. Scientists gave nicotine to mice lacking that particular neural pathway, and the chemical didn’t contribute to weight loss as it does with most mice. The finding could help scientists find a solution to help smokers quit without seeing the numbers inch up on the scale. But the gain is usually only about 10 pounds—seemingly too little anyway to outweigh the benefits of quitting, like cutting cancer and heart attack risk. If gaining weight is a concern, however, researchers suggest using a nicotine-based method of quitting.