Coffee: Drink espresso could reduce chances of getting dementia, new research suggests

The dark shot of coffee destroys rogue proteins that gather in the brain and kill neurons - and it apparently works even if consumed in an espresso martini cocktail.

Lead author Professor Mariapina D'Onofrio, of Verona University, said: "Espresso coffee mitigates the aggregation and condensation of Alzheimer's associated tau."

The 'tangles' are one of the key causes of dementia - slowing thinking and memory skills. In healthy people, tau helps stabilise structures in the brain. But in neurodegenerative diseases, it can clump together into 'fibrils'.

Lab experiments showed espresso prevents them. Around 96 per cent of the Italian population drink it on a daily basis.

Prof D'Onofrio said: "As the concentration of espresso extract, caffeine or genistein increased, fibrils were shorter and didn’t form larger sheets, with the complete extract showing the most dramatic results.

"Shortened fibrils were found to be non-toxic to cells, and they did not act as 'seeds' for further aggregation."

The team pulled espresso shots from store-bought beans, then characterised their chemical makeup using a scanning technique called nuclear magnetic resonance spectroscopy.

They chose caffeine and trigonelline, both alkaloids, the flavonoid genistein and theobromine, a compound also found in chocolate, to focus on in further tests.

Prof D'Onofrio said: "Whether enjoyed on its own or mixed into a latte, Americano or even a martini, espresso provides an ultra-concentrated jolt of caffeine to coffee lovers.

"But it might do more than just wake you up. Espresso compounds can inhibit tau protein aggregation — a process that is believed to be involved in the onset of Alzheimer's disease."

Dark, rich espresso is regularly drunk by around 13 per cent of people in the UK. It's often served after an evening meal. Composed of over 1,800 chemical components, estimates put the number of cups of coffee drunk globally at more than a couple of billion each day.

The norm for brewing an espresso is to grind a relatively large amount of coffee beans, around 20g, as finely as possible.

The fine grind, common sense goes, means more surface area exposed to the brewing liquid. This ought to boost extraction yield - the fraction of the ground coffee that actually dissolves and ends up in the final drink.

To 'pull' an espresso shot, hot water is forced through finely ground coffee beans, creating a concentrated extract.

This is often used as a base for other drinks, including the trendy espresso martini.

Prof D'Onofrio said: "Recent research has suggested that coffee could also have beneficial effects against certain neurodegenerative diseases, including Alzheimer's.

"Although the exact mechanisms that cause these conditions are still unclear, it's thought that a protein called tau plays a significant role."

Italians knock back some 30 million espressos a day in porcelain cups or little glasses, with or without a splash of milk - and see each one as a gesture of friendship.

Prof D'Onofrio said: "Drinking espresso has become a habit in many countries due to its pleasant taste.

"For many years coffee consumption was associated with health risks. Regular consumption has been linked to reduced risk of premature death.

"However recent studies showed that when consumed in moderation this soft drink could have beneficial effects thanks to its biological properties."

Coffee is rich in antioxidants and plant chemicals that dampen inflammation.

Regular consumption has been linked to reduced risk of premature death - protecting against type 2 diabetes, heart disease, liver and some cancers.

Prof D'Onofrio added: "Coffee extracts contain a large variety of bioactive compounds exhibiting health-beneficial effects. We were able to identify the most abundant constituents.

"We have presented a large body of evidence that espresso coffee - a widely consumed beverage - is a source of natural compounds showing beneficial properties in ameliorating tau-related pathologies."

The findings in the Journal of Agricultural and Food Chemistry could also pave the way toward developing other bioactive compounds.