Could coffee increase your lifespan?

Researchers claim that adults who drink moderate amounts (1.5 to 3.5 cups per day) of coffee are less likely to die during a seven year follow up period, compared to non-coffee drinkers.

This study is based on those who consumed the beverage unsweetened as well as those who added sugar to their coffee; results for those who used artificial sweeteners were less clear. 

Previous studies observing the effects of coffee on health have already linked coffee drinkers with longer lives, but unlike this latest research, the team state that none – until now – have distinguished between unsweetened coffee and coffee consumed with sugar or artificial sweeteners.

The researchers from Southern Medical University in Guangzhou, China, used data from the UK Biobank to evaluate the associations of consumption of sugar-sweetened, as well as artificially sweetened and unsweetened coffee with all-cause and cause-specific mortality.

More than 171,000 participants from the UK without known heart disease or cancer were asked several dietary and health behaviour questions to determine coffee consumption habits. The authors found that during the seven-year follow up period, participants who drank any amount of unsweetened coffee were 16 to 21 percent less likely to die than participants who did not drink coffee. They also found that participants who drank 1.5 to 3.5 daily cups of coffee sweetened with sugar were 29 to 31 percent less likely to die than participants who did not drink coffee. The authors flagged in their study that adults who drank sugar-sweetened coffee, only added around one teaspoon of sugar per cup on average. Furthermore, the average amount of daily sugar per cup of coffee recorded in this analysis is much lower than specialty drinks at popular coffee chain restaurants, and the researchers advised that this may influence results.

The authors also noted that, while coffee has qualities that could make health benefits possible, confounding variables such as socioeconomic status and diet, among other lifestyle factors, may impact findings. They also highlighted that the participant data is at least 10 years old and collected from a country where tea is a similarly popular beverage. 

Based on this data, the researchers suggest that clinicians can tell their patients that there is no need for most coffee drinkers to eliminate the beverage from their diet, but to be cautious about higher calorie specialty coffees.

The findings of this study are published in Annals of Internal Medicine.