Lighting the Fire Within (IMAGE) University of Utah Health Caption Scientists at University of Utah Health report a lipid, acylcarnitines (AC on the superwoman's suit), as a newly discovered fuel source for brown fat, a 'good fat' that generates body heat in response to the cold. Credit Paulo Temblador and Cell Metabolism Usage Restrictions With credit License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.