Does coffee help us live longer?

A recent study concludes that drinking coffee, in moderate amounts, reduces the risk of death. What is it really ?

The scientific studies that highlight the benefits of coffee for health are numerous, so much so that one would be tempted to multiply coffee breaks to reduce the risk of contract various diseases or even the risks of dying as the latest study on the benefits of coffee suggests. The conclusion of the study published in Annal of Intern Medicine says that ” moderate consumption of unsweetened or sweetened coffee is associated with a lower risk of death “. A less robust association, from a statistical point of view, when we consider coffee sweetened or embellished with a sweetener. Does this justify drinking coffee to grab years of life? Unfortunately, it’s not that simple.

A link between coffee and mortality?

The study in question is an observational study, that is to say that it can only highlight a link and not a causality. It therefore does not prove that coffee is directly responsible for the decrease in mortality observed between non-consumers and coffee consumers. The results were obtained from 171,616 participants, with an average age of 55, for whom data on their lifestyle, demographic profile and diet were available in the database medical UK BioBank.

However, the estimate of the risk of death was calculated on a much smaller sample, since 3,117 deaths were recorded during the time of the study. ” This is sufficient to give estimates of mortality rate comparisons during follow-up, but there is a great deal of statistical uncertainty in these estimates. », explains Kevin McConwayEmeritus Professor of Applied Statistics at theOpen University United Kingdom.

Another element that calls for caution: the scientists did not include changes in coffee consumption in their study. Half of the participants entered their coffee consumption at some point during the follow-up, and that was it. This data is not representative of the participants’ actual coffee consumption during the ten-year follow-up. ” Reported coffee drinking patterns are almost 10 years old and patterns may have changed since […] which may be relevant matter associated health and mortality », underlines Annette Creedon of the British Nutrition Foundation.

Differences in participants’ lifestyles or diets may also contribute to the difference in mortality between coffee drinkers and non-drinkers. While scientists can make adjustments to eliminate these third-party factors, it is impossible to completely get rid of them.

Multiplying coffees will not increase your life expectancy. In all likelihood, the consumption of this drink in reasonable quantities is not bad for your health, with the exception of very specific cases where it is not recommended, any assertion beyond this would be risky.