Ancient skeletal remains found at Dakhleh are raising intriguing medical questions. The antibiotic tetracycline was ingested naturally and prevented infectious diseases, but an anaemic condition indicating nutritional stress was also universal. Two cancers and spina bifida have been isolated. DNA technologies applied to ancient bones have provided accurate profiles of Dakhleh populations thousands of years ago. Tetracycline was accidentally produced at the site. It was a mould growth on stored wheat, which would have been ground with the grain into flour for bread making.