Those who drink between one and two cups of coffee a day are at the lowest risk of suffering from Alzheimer’s and other cognitive disorders, a study has found.
The study, published in Clinical Nutrition, pooled evidence from different studies to gauge the influence of different coffee drinking patterns on cognitive disorders, such as Alzheimer’s disease, dementia and cognitive decline.
Results showed that compared with those who drunk less than one cup of coffee a day, those drinking between one and two cups had a lower occurrence of cognitive disorders.
The Chinese research team said a dose-response association was found between the risk of developing cognitive disorders and coffee intake, with analysis indicating a ‘J-shaped’ curve relationship.
“In conclusion, the results of our study, involving 9 independent cohort studies, provide significant evidence of an inverse and a J- shaped curve relationship of coffee drinking with the occurrence of cognitive disorders,” wrote the authors.
“The lowest risk of cognitive disorders was observed at a daily consumption level of 1-2 cups of coffee,” they said. “Further prospective long-term randomized controlled trials (RCTs) are still demanded to firmly establish the observed relation.”
The new study comes as researchers seek to identify modifiable lifestyle factors, such as coffee consumption, to help prevent cognitive disorders.
It also comes amid a backdrop off previous studies providing inconsistent conclusions on the impact of coffee consumption on the development of cognitive disorders.
The team searched two databases for records related to coffee consumption and the risk of cognitive disorders.
Pooled data – which included data from 34,282 people who took part in nine studies – was then classified into three categories of coffee consumption: less than one cup per day; between one and two cups per day; more than three cups a day.
While drinking between one and two cups of coffee was linked to a lower risk of cognitive disorders, the team said that drinking more than three cups of coffee a day was not significantly associated.
They said that findings from this latest study corroborate findings from previous studies – including one involving a sample of Italians, which had also suggested that consuming a moderate amount of coffee (between one and two cups per day) meant there was the less chance of developing cognitive impairment.
Volume 36, Issue 3, June 2017, Pages 730–736, doi: 10.1016/j.clnu.2016.05.015
“Coffee intake and the incident risk of cognitive disorders: A dose response meta-analysis of nine prospective cohort studies”
Authors:Lei Wu, Dali Sun, Yao He