Over 30 years ago, one researcher chose a small group of nuns as subjects for a study on aging and brain deterioration. Through the years, the study has grown to include nearly 700 sisters across the United States and continues to reveal groundbreaking insights into the aging process and Alzheimer’s disease.
Learn more about “The Nun Study” and what it is teaching us about Alzheimer’s and dementia.
The Nun Study
David Snowdon began studying nuns in Mankato, Minnesota, 31 years ago in 1986. Snowdon was hopeful that he could learn why the brain deteriorated with age in some people and not others.
“The Nun Study,” as it quickly became known, grew to 678 sisters across the U.S. When the study began, the nuns ranged in age from 75-103 and included a wide range of health, with some functional and healthy and some severely disabled.
While nuns may not seem representative of the larger population, leading similar lifestyles free from excessive alcohol consumption and smoking, living and working in similar environments — and sharing a gender — made the nuns great study participants.
Because nuns share so many environmental variables, it eliminates variables that most studies have to consider when reaching conclusions. The nuns also had medical records that spanned throughout their entire lives, giving researchers unparalleled access to family and medical histories, education records, social and work information.
All of the sisters participated in annual bloodwork, cognitive assessments, medical exams and physical assessments throughout the study, and even agreed to brain donation at death for future research.
What Nuns Are Teaching Us About Alzheimer’s
Before taking their vows, the nuns each wrote an autobiographical statement, which gave researchers insight into their linguistic ability. Past research has indicated both oral and written linguistic ability is an indicator of cognitive ability and a high level of linguistic ability earlier in life may protect against cognitive decline in old age.
Snowdon then evaluated the sisters’ autobiographies to see if their linguistic ability could predict their risk of Alzheimer’s and related types of dementia.
He gathered the autobiographies almost 60 years after they were written, and then asked the nuns who were between the ages of 75-95 years old to participate in a cognitive assessment. He also obtained autopsy results from 14 nuns who had died during that time period. He concluded that the sisters who demonstrated a low level of linguistic ability in their autobiographical statements had lower cognitive test scores later in their lives.
Researchers believe that this may mean the brain begins showing signs of deterioration very early in life, even 50-60 years before symptoms develop.
The Nun Study continues to yield fascinating results, giving us unique insight into the aging process.
Do you feel that this study will help researchers further understand the relationship between aging and cognitive disease? Share your thoughts about Alzheimer’s and aging with us in the comments below.