How strong coffee could prevent Alzheimer’s – even if it is in an espresso martini

Drinking an espresso - even in a cocktail - a day might protect against Alzheimer’s disease, new research has found.

A study by the University of Verona in Italy showed the dark shot of coffee destroys rogue tau proteins that gather in the brain and kill neurons, a process that is believed to be involved in the onset of the neurodegenerative disease.

The study’s lead author, professor Mariapina 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.”

In healthy people, tau helps stabilise structures in the brain but, in neurodegenerative diseases, it can clump together into ‘fibrils’. These tangles are one of the key causes of dementia – slowing thinking and memory skills.

Lab experiments conducted showed the consumption of espresso prevents these from forming. Researchers also discovered the fibrils were shorter and didn’t form larger sheets as the concentration of espresso extract, caffeine or genistein increased.

“Shortened fibrils were found to be non-toxic to cells, and they did not act as ‘seeds’ for further aggregation,” professor D’Onofrio explained.

Her 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.

Professor D’Onofrio said that the beneficial effects of espresso were found whether the beverage was enjoyed on its own or mixed into a latte, Americano or even an espresso martini.

Dark, rich espresso is regularly drunk by around 13 per cent of people in the UK, and it is often served after an evening meal. 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 20 grams, as finely as possible. To ‘pull’ an espresso shot, hot water is forced through these finely ground beans, creating a concentrated extract. This is often used as a base for other drinks, including the trendy espresso martini.

Professor D’Onofrio said that while coffee consumption has typically been associated with health risks, recent studies have showed the drink might have beneficial effects when consumed in moderate quantiies – 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.

The academic added: “We have presented a large body of evidence that espresso coffee is a source of natural compounds showing beneficial properties in ameliorating tau-related pathologies.”

The findings were published in the Journal of Agricultural and Food Chemistry.