That’s according to new research from Karolinska Institutet in Sweden.
A team comprising researchers from the Department of Dental Medicine and the Aging Research Center (ARC) at Karolinska Institutet and from Karlstad University in Sweden have looked at tooth loss, chewing ability and cognitive function in a random nationwide sample of 557 people aged 77 or older.
It found that those older patients who had difficulty chewing hard food such as apples had a significantly higher risk of developing cognitive impairments.
This correlation remained even when controlling for sex, age, education and mental health problems, variables that are often reported to impact on cognition.
Whether chewing ability was sustained with natural teeth or dentures also had no bearing on the effect.
The results are published in the Journal of the American Geriatrics Society (JAGS).
The study was financed with grants from several funds, including the Swedish Council for Working Life and Social Research and the Swedish Research Council.