Listen to the radio documentary “Aging with grace“ and discover the story of 678 American nuns who donated their brain to Dr. Snowdon to examine the mysteries of aging and Alzheimer’s.

In 1986 Dr David Snowdon approached the sisters at the convent of the School Sisters of Notre Dame in Minnesota. An order of Catholic sisters with their uniform life-styles were perfect for an examination of the ageing process. It was the beginning of the Nun Study which experts still consider to be one of the most innovative efforts to answer questions about who gets Alzheimer’s disease and why.

An unlikely friendship developed between Snowdon and the sisters. Some of the nuns recall how they would look forward to the annual cognitive and memory tests. “We cared about Dr Snowdon and he cared about us”, says one of the nuns. “He would walk with us and talk with us and we looked forward to his visits.”

A breakthrough came when the Snowdon team came across a filing cabinet full of diaries written by the sisters when they’d entered the order. The team worked out that those sisters who used more complex sentences and ideas were less likely to develop Alzheimer’s later on. As they died, the brain of each sister was analysed for further information and these samples are now stored at the University of Minnesota along with the brains of other sisters who have continued to participate in this extraordinary longitudinal study.

More recently, Dr. Sanjay Gupta also discussed the study on CNN’s vital+signs series. Watch the episode here.