Age range 9+

Creswell John Eastman AO is the Clinical Professor of Medicine at Sydney University Medical School, Principal of the Sydney Thyroid Clinic and Consultant Emeritus to the Westmead Hospital. Eastman is an endocrinologist and has directed or conducted research and public health projects into elimination of iodine deficiency disorders (IDD) in Malaysia, Indonesia, Laos, Cambodia, Thailand, several Pacific Islands, Hong Kong, China and Tibet and Australia. For his work in remote areas of China, he has been dubbed the 'man who saved a million brains'.

In 2013 Eastman expressed concern that IDD may be affecting Australian children's ability to perform at school and reiterated that view in 2016. While the initial focus was mostly on indigenous children, he recently expanded it to include all children.

Cres was awarded Membership of the Order of Australia in 1994 for his contributions to Medicine, particularly in the field of Endocrinology, and was awarded the Premier's Gold Service Award in 2002 for development of the NSW Forensic DNA service laboratory.