Could coffee prolong your life? Scientists think it might

A new study suggests coffee can increase your lifespan. But how true is that claim?
Alice Cooke
Drinking coffee.
Drinking Coffee.

Interesting Engineering.

- A recent study claimed coffee could prolong your life and reduce the risk of disease

- It also suggested that this is not dependent on whether the coffee contains caffeine

- Scientists say that any relationship between coffee and chronic disease or mortality should be interpreted “cautiously”

This story first appeared in our subscriber-only weekly Blueprint newsletter. Receive exclusive interviews and analyses like this, direct to your inbox every Sunday, by subscribing to IE+.

Following the news that consuming two to three cups of decaffeinated, ground, and instant coffee can lower the risk of developing cardiovascular disease and dying early, according to a recent Australian study, IE wanted to know more.

The study in question monitored the health (and, in some cases, deaths) of around 450,000 volunteers in the U.K. for seven years. They were all over the age of 40 and had no previously documented cardiovascular disease.

It found that those who drink between one-and-a-half to three-and-a-half cups of coffee per day were 16 percent to 21 percent less likely to die from all-cause, cancer-related and cardiovascular disease-related mortality during the study period than non-coffee drinkers.

It also found that, compared to non-coffee drinkers, coffee drinkers were less likely to develop cardiovascular disease and die “from any cause in general”. Which seems quite the claim.

It did concede though that this was dependent on the amount and the type of coffee consumed.

Interestingly, the biggest decrease in mortality from cardiovascular disease was observed in those who consumed two to three cups of decaffeinated, ground, or instant coffee per day.

And, it concluded that the benefits of the drink come, in fact, from chemicals in coffee beans, rather than caffeine.

The study also found that those who drank one to five cups of ground or instant coffee per day had the lowest risk of developing arrhythmia, or an abnormal heartbeat, while ‘decaf’ didn’t show any protective effects against arrhythmia.

Good cop or bad cop?

Studies purporting to show coffee’s health benefits are nothing new. Coffee has, in the past, been linked to reduction of risk of Parkinson’s disease, type two diabetes, heart disease, prostate cancer, melanoma, depression and suicide, cirrhosis of the liver, and liver cancer. But none of these claims have been substantiated.

But on the flipside, it was only as recently as 1991 that the World Health Organization included coffee on a list of possible carcinogens. It was later removed from that list, but the point is, scientific opinion as to whether coffee is good for you or not is anything but black and white, or espresso or latte, if you will.

A 2015 study tracked more than 200,000 participants for 30 years. It found that drinking three to five cups of coffee a day made you 15 percent “less likely to die from all causes of mortality”, including cardiovascular disease, Parkinson’s disease and suicide.

A more recent study, in 2018, tracked more than 500,000 participants across 10 years. Compared to non-coffee drinkers, participants who downed six to seven cups daily had a 16 percent lower risk of early death.

But the benefits in both instances related to participants who drank both caffeinated and decaffeinated coffee – suggesting that the magic ingredient (or ingredients) may have nothing to do with the caffeine.

Could coffee prolong your life? Scientists think it might
Drinking coffee.

Interesting Engineering.

So there’s something in it, but what?

Professor Peter Kistler of the Baker Heart and Diabetes Research Institute, tells IE: “Coffee contains more than 100 biologically active components. It is likely that the non-caffeine compounds were responsible for the positive relationships observed between coffee drinking, cardiovascular disease, and – ultimately – survival.”

On a similar vein, Erikka Loftfield, Ph.D., M.P.H., an Earl Stadtman Investigator at the Metabolic Epidemiology Branch of the National Cancer Institute’s Division of Cancer Epidimiology and Genetics, which is in Maryland, Texas, was part of a study called “The impact of coffee subtypes on incident cardiovascular disease, arrhythmias, and mortality: long-term outcomes from the U.K. Biobank”.

Loftfield (who enjoys a couple of cups of coffee most days) tells IE that: “For example, polyphenols in coffee may have antioxidant and anti-inflammatory effects.”

Indeed, coffee is known to be a source of vitamin B2 (riboflavin), magnesium, and plant chemicals, alongside polyphenols, including chlorogenic acid and quinic acid, and diterpenes such as cafestol and kahweol.

It is also thought to be beneficial as an anti-inflammatory; in producing reduced insulin resistance; by containing high amounts of antioxidants that can prevent or delay cell damage; by containing lignans, which disrupt growth and spread of cancer cells; and by containing chlorogenic acid, which lowers blood sugar levels.

But again, none of this has been scientifically proven, so it’s all a bit pie in the sky.

So what now?

As to where the research to this end might go next, Loftfield says: “Clinical trials of intermediate endpoints have, to date, largely failed to identify beneficial effects of coffee. In short, more research is needed to better understand the biology underlying the potential health effects of coffee; one way we are doing this is by incorporating molecular data, including genetics and metabolites measured in blood and urine, into our observational studies.”

But are we able to make a definitive association between coffee and positive health benefits? For the moment, Loftfield is sceptical: “Most of what we know about the relationship between coffee and chronic disease or mortality derives from observational studies; these studies cannot determine causality, and the findings should be interpreted cautiously.”

“However,” she adds, “Other kinds of studies are impractical, such as randomizing a very large group of adults to be long-term coffee drinkers or non-drinkers so I am not sure if we will ever have a definitive answer. Nevertheless, the consistency of results across large, geographically diverse, prospective studies should offer reassurance to coffee drinkers worldwide.”

Don’t give up the Joe just yet though, as Kistler adds: “The results of the Australian study suggest that mild to moderate intake of ground, instant, and decaffeinated coffee should be considered part of a healthy lifestyle.”

The general concencus appears to be that the data shows an association between daily coffee consumption and a reduced risk of dying …but that doesn’t mean there’s direct causation. So enjoy your coffee by all means, but don’t rely on it to prolong your life just yet.