Leptin, as opposed to lipten, is a hormone which is produced in adipose (fat) tissue. It is involved with regulation of body weight. The release of leptin has been found to be greater in obese adults and has been noted be decreased during fasting. In Sweden, Leptin levels in a group of exclusively breastfed newborns were followed. Levels were found to positively correlate with amount of fat tissue and negatively correlated with amount of weight loss (in other words, the more weight lost the lower the leptin levels, over time). The reference is: Pediatrics March 1998;101:429-32. Danny Hirsch, MD, FAAP, CLC Director, Lactation Institute of Westchester Division of Newborn Medicine Westchester & Sound Shore Medical Centers Assistant Professor of Pediatrics New York Medical College Valhalla, NY, USA [log in to unmask] *********************************************** The LACTNET mailing list is powered by L-Soft's renowned LISTSERV(R) list management software together with L-Soft's LSMTP(TM) mailer for lightning fast mail delivery. For more information, go to: http://www.lsoft.com/LISTSERV-powered.html