People with a balanced and varied daily diet are about 44 percent less likely to experience cognitive decline connected to dementia than those who don't eat as well, new research by the National Center for Geriatrics and Gerontology has found.
The center believes the results show that both a large variety of nutrients and meal-related activity have a positive influence on the brain. The research team's paper has been published in the English-language journal of The Japan Geriatrics Society.
Center laboratory head Rei Otsuka and fellow researchers have administered a cognitive function test scored out of 30 to some 1,200 subjects aged 60 and above since 2000. The team then studied the meals over three day periods for the 570 subjects aged 60 to 81 who scored 28 or higher on the test, and quantified the variety and balance of the meals based on the amounts and types of food the people ate.
Researchers divided the subjects into four groups, ranked by how much variety they had in their diets. They then examined the relationship between the subjects' eating habits and the results of every cognitive function test they took beyond the first. The results showed that the group with the best dietary variety showed little decline in its test scores and was 44 percent less likely to exhibit cognitive decline than the group with the worst mealtime variety.
"We think that cognitive function is maintained by consuming a broad range of nutrients," commented Otsuka. "Shopping, cooking and other meal preparation activities also likely have a positive influence on the brain."