Human Health & Plants Research: Lifestyle, Gardening, and Dementia

Charlie GuyDementia has been estimated to afflict about six million in the United States in 2018 and is projected to increase to 14 million by 2050. Worldwide, the economic cost of dementia is estimated to be approaching one trillion dollars annually while also creating devastating personal and family hardships.  Numerous studies have shown a lifestyle that includes regular cognitive and physical activity of various kinds is associated with a reduced likelihood of the onset of dementia.  Gardening is often found to be a type of physical activity linked with a lower incidence of dementia.  A recent study on lifestyles out of Japan by Shimada and colleagues (2018) examined daily living activities and social roles with respect to the incidence of the onset of dementia over a period of about 43 months in a population of 4,564 men and women ages 65 years and above.  During the course of the study, 219 (4.8%) participants were diagnosed with the onset of dementia.  Of 16 lifestyle activities examined, four activities based on a proportional hazards regression model for the total population showed that the probability of developing dementia was statistically reduced.  The four activities identified were 1, engaging in daily conversation; 2, driving a car; 3, shopping; and 4, gardening.  For men, only driving a car was associated with a reduced probability of acquiring dementia, while for women daily conversation, driving a car, and gardening was associated with a lowered probability of dementia.  The study authors conclude that specific lifestyle activities including gardening may play important roles in reducing the rate of onset of dementia in older adults.

Charles Guy
Emeritus and Courtesy Professor
 Department of Environmental Horticulture, University of Florida