The way coffee is brewed appears to be linked to how quickly the body ages, according to a new study. Filter coffee, strained through a paper filter, showed signs of slowing biological aging, while instant coffee showed the opposite pattern, associated with accelerated aging.
A research team at Chongqing Medical University in China recently published a paper in the international journal npj Science of Food, analyzing data from 49,414 adults registered in the UK Biobank. The average age of those analyzed was 56.4, and 44.3% were women. Of the participants, 91% lived in England, and 65% had a history of being diagnosed with high blood pressure. Instant coffee had the highest average daily intake at 1.5 cups, followed by filter coffee at 0.7 cups and other brewing methods at 0.03 cups. Of the respondents, 23% said they chose decaffeinated coffee, and 33% said they drank it with milk.
The research team examined both telomere length (rLTL), known as the cell's biological clock, and biological age calculated from blood test results (PhenoAge and KDM-BA). The group that drank instant coffee had a biological age exceeding their actual age, compared with the group that drank no coffee, and their cellular aging was also faster. In the filter coffee group, both indicators moved in the opposite direction. However, the gap itself was not large. The acceleration of physical age in the instant coffee group generally amounted to only one to two months.
The differences were more pronounced in some groups. Men who drank three or more cups of instant coffee a day, people aged 60 and older, and smokers showed a higher biological age than those who did not drink coffee. Conversely, men who drank three or more cups of filter coffee a day tended to show a lower physical age. The research team concluded, "Filter coffee intake tended to slow both physical age increase and cellular aging, whereas instant coffee was associated with signals that accelerate aging."
The results should be interpreted with caution. This study was a cross-sectional study that examined data from a specific point in time, making it difficult to conclude that brewing method directly determines aging. The reliance on survey responses for intake and the fact that most participants were white were also cited as limitations. The research team added that long-term follow-up studies would be needed to clearly establish causality.
