Whether we have an espresso shot, a frothy cappuccino or a milky latte, many of us are as reliant on a caffeinated pick-me-up as we are on our alarm clock. But now there is an increasing amount of evidence to suggest that the many ingredients within coffee could help with aspects of our health.
The latest data have emerged from the University of Verona, where researchers showed that doses of espresso could prevent a toxic protein called tau from clumping together in cells in a petri dish. This is particularly interesting because the steady accumulation of tau in the brain is a contributing factor to Alzheimer’s disease.
Dr Federica Amati, a medical scientist and nutritionist at Imperial College London, has been intrigued by the various benefits of coffee for many years. She refers to a major 15-year study of more than half a million participants, known as the European Prospective Investigation into Cancer and Nutrition (Epic), which showed that people who drank more coffee were less vulnerable to a range of chronic illnesses.
“Data keep coming out which show that coffee drinking is protective for health,” she says.
However, there are caveats. “Whether you have milk or not doesn’t seem to make a difference, but as soon as it’s sweetened with sugar, you start losing the beneficial effects,” she says. “Some studies also suggest that espresso drinking is the best.”
So, how much should you drink? Experts at Nutritank, who provide medical education to healthcare professionals on food, nutrition and lifestyle medicine, say that Harvard University recommends two to five cups of coffee daily.
It is also not necessarily suitable for everyone. People with irritable bowel syndrome, or genetic factors that mean they cannot process caffeine so well, will likely not benefit from coffee.
“It is important to remember that UK guidelines are that no more than about two and a half cups of coffee are consumed in one sitting, or five cups per day,” says Dr Ally Jaffee, NHS doctor and co-founder of Nutritank. “Daily consumption of more than seven and a half cups of coffee has been suggested to have a negative impact on heart and brain health.”
So, what can coffee do for you?
Reduces risk of colorectal cancers
One of the findings of the Epic study was that coffee lowered the risk of colorectal cancers. Dr Amati says this is likely to be because it encourages bowel turnover, helping to flush toxins through the system.
“Coffee has a laxative effect when you drink it,” she says. “Essentially, it’s really good to promote regular bowel movements and that is very important.”
Coffee drinkers have also been found to have different species of bacteria in their gut microbiomes compared with non-coffee drinkers. This is believed to be one of the strongest protective factors against colorectal cancers.
Dr Francesca Jackson-Spence, an NHS doctor who provides medical information on her Instagram channel @drfrankiejs, says that coffee contains chemicals called polyphenols, which protect against inflammation in the body and repair damage to cells. These chemicals are found in decaffeinated coffee, too, which has also been found to have health benefits.
“These plant-based chemicals act as prebiotics and soluble fibre to feed the various species of microbes in the gut and support gut microbiome diversity, which has been shown to have an important role in our long-term health,” she says.
Improves brain function in later life
While it is far too early to say that coffee drinking can prevent a highly complex disease such as Alzheimer’s, researchers feel there is an association between coffee drinking and better cognition in later life.
Mariapina D’Onofrio, a researcher at the University of Verona who led the recent study into tau protein accumulation, believes that coffee may help to promote normal brain functioning in middle age and later life. “I believe that the components in coffee may be helpful in maintaining neuronal activity and plasticity,” she says.