John D. Wark MBBS, PhD, FRACP

John D. Wark is Head of the Royal Melbourne Hospital Bone and Mineral Service and Broadmeadows Osteoporosis Centre. Dr. Wark is Professor of Medicine at the University of Melbourne, Australia. He has an international reputation in the bone field and is known for his work on vitamin D metabolism; for studying twins of different ages and genders over many years; for the role of physical activity in bone health and for his work with the World Health Organization as a consultant on osteoporosis and menopause. He also works with merino sheep as an animal model of osteoporosis. Sheep are more suitable than many non-primates because they ovulate year-round (like women) rather than sporadically, or once a year.