Taking regular afternoon naps may not be a bad habit after all as a study conducted by the researchers at the Shanghai Jiao Tong University in China reveals that short naps in the afternoon can keep the brain sharp.
The study which was published in the journal General Psychiatry has linked afternoon naps to better mental agility. Prof. Wei Li, one of the researchers behind the study remarked that afternoon naps are associated with better locational awareness, verbal fluency and working memory.
The team conducted their study on 2,214 visibly healthy people with a minimum age of 60 years who were living in several large cities all across China. While 1,534 participants took a regular afternoon nap, 680 chose otherwise.
All participants underwent a series of health checks and cognitive assessments, including the Mini-Mental State Exam (MMSE) to check for dementia.
All participants in the study were sleeping close to 6.5 hours on average every night. The research team defined afternoon naps as “periods of at least five consecutive minutes of sleep which did not extend more than 2 hours and taken after lunch.”
Afternoon naps varied among participants where some chose to sleep every afternoon while others did it just once a week.
Dementia screening tests conducted on participants included 30 points of reference which measured several aspects of cognitive ability, and higher function, including visuospatial skills, working memory, attention span, problem-solving, locational awareness and verbal fluency.
The study revealed that MMSE cognitive performance scores among afternoon nappers were significantly higher when compared to those who did not nap. Notable differences were visible in locational awareness, verbal fluency, and memory as well.
Discussing the outcome of the study, researchers observed that with very little information available on critical components such as the duration or timing of the naps taken, the observational study cannot establish a cause for better mental agility.
One of the possible theories the researchers proposed was that inflammation is a mediator between mid-day naps and poor health outcomes and inflammatory chemicals have an important role in sleep disorders.
Researchers stated that sleep regulates the body’s immune response and napping is thought to be an evolved response to inflammation as people with higher levels of inflammation also nap more often.