Drinking green tea may improve some of the intellectual capabilities in people with Down's syndrome, new research suggests.
The study found that epigallocatechin gallate - a compound present in green tea - has the potential to improve a range of different brain functions in those living with the syndrome when paired with cognitive stimulation activities.
"This is the first time that a treatment has shown some efficacy in the improvement of some cognitive tasks in persons with this syndrome," lead author Dr Mara Dierssen said in a statement.
"It must be made clear that our discovery is not a cure for Down's syndrome and that our results have to be proven in larger populations, but it may be a treatment to improve these individuals' quality of life."
According to the World Health Organisation, Down's syndrome affects approximately one out of 1,000 people in the world and is the most common cause of genetic-origin intellectual disability.
It is caused by a trisomy of chromosome 21. In other words, people with Down's syndrome have three, not two, copies of chromosome 21.
Along with fellow study lead Dr Rafael de la Torre, Dr Dierssen and her team sought to investigate how the green tea compound could limit the affects of the additional chromosome.
They worked with 84 people with Down's syndrome aged between 16 and 34 for the year-long study.
Half the study participants received cognitive training while taking a placebo pill, while the other half practiced the same exercises while receiving the green tea compound.
Those in the latter group showed score improvements in visual recognition memory, the ability to focus on tasks and adaptive behaviour (social and practical skills needed to live independently).
"The results suggest that individuals who received treatment with the green tea compound, together with the cognitive stimulation protocol, had better score in their cognitive capacities," Dr de la Torre said.
However, the authors acknowledged that further studies with a larger number of participants were needed before the findings could be considered conclusive.
The study is published in full in The Lancet Neurology.