A cup of coffee a day could offset the effects of the most common form of dementia, Alzheimer's disease, new research has claimed.
Caffeine blocks the negative effects of high cholesterol that have been linked to the disease, according to a recent study.
The findings, published in the Journal of Neuroinflammation, are based on research by scientists at the University of North Dakota School of Medicine and Health Sciences.
Previous studies have shown that high levels of cholesterol break down the blood brain barrier, which can then no longer protect the central nervous system from the damage caused by blood-borne contamination.
Leakage in the blood brain barrier occurs in a number of neurological disorders, such as Alzheimer's disease.
Jonathan Geiger, of the University of North Dakota School of Medicine and Health Sciences, said: "For the first time we have shown that chronic ingestion of caffeine protects the blood brain barrier from cholesterol-induced leakage."
It is estimated that 700,000 people in the UK suffer from dementia, with about two thirds of these suffering from Alzheimer's.
Dr Susanne Sorensen, head of research at the Alzheimer's Society, said: "This is the best evidence yet that caffeine equivalent to one cup of coffee can help protect the brain against cholesterol.