Appetite-Control Hormone May Cut Alzheimer's Risk High leptin levels linked to lower rates of disease By Rob Quinn, Newser Staff Posted Dec 16, 2009 5:00 AM CST 4 comments Comments The hormone leptin, discovered in the '90s, plays a critical role in regulating appetite and weight. (Shutter Stock) (Newser) – High levels of a hormone that regulates appetite has been linked to a much lower risk of developing Alzheimer's disease in new research. Scientists probing the connection between obesity and Alzheimer's found that out of the 198 volunteers studied, those with the highest levels of leptin were four times less likely to develop the disease than those with the lowest, raising new possibilities for treatment. Leptin, produced by fat cells, has been shown to play a vital role in regulating weight and scientists now believe it also affects brain function. If further studies back up their findings, leptin levels could become one of the main "biomarkers for healthy brain aging and, more importantly, may open new pathways for possible preventive and therapeutic interventions," the researchers write.