For millions of people, coffee is a non-negotiable part of the morning routine. But could the way your coffee is prepared influence how your body ages?
According to a new study published in npj Science of Food, the answer may be more nuanced than previously thought. Researchers analysing data from nearly 50,000 adults in the UK Biobank found that filtered coffee consumption was associated with markers of slower biological ageing, while instant coffee intake was linked to markers of accelerated biological ageing.
The findings suggest that brewing method, not just the amount of coffee consumed, may influence the beverage’s relationship with healthy ageing.
However, experts caution against jumping to conclusions.
The study was observational and cross-sectional, meaning it identified associations rather than proving that one type of coffee causes people to age faster or slower. Lifestyle, diet, genetics and underlying health conditions may also contribute to the differences observed.
Here’s what the research found, what biological ageing actually means, and why scientists say more studies are needed before changing dietary recommendations.
What Is Biological Ageing?
Unlike chronological age, which simply reflects the number of years a person has lived, biological age refers to how well the body’s cells, tissues and organs are functioning. Two people of the same chronological age may have very different biological ages depending on genetics, lifestyle, diet, environmental exposures and chronic disease risk.
Scientists increasingly use biological ageing markers to estimate an individual’s overall health status and future risk of age-related diseases. In the latest study, researchers assessed biological ageing using three validated measures:
Relative leukocyte telomere length (rLTL): A marker of cellular ageing. Shorter telomeres are generally associated with ageing and chronic disease.
PhenoAge Acceleration (PhenoAgeAccel): A biological age estimate derived from clinical biomarkers.
Klemera-Doubal Method Biological Age Acceleration (KDM-BAAccel): Another validated measure estimating biological age from physiological indicators.
What Did The Study Find?
The researchers analysed dietary and health data from 49,414 UK Biobank participants, whose average age was 56.4 years. Participants reported their coffee intake through repeated dietary questionnaires, while biological ageing markers were measured using blood tests and clinical parameters.
The results showed distinct differences depending on the type of coffee consumed:
Filtered coffee was associated with lower biological age acceleration scores and generally longer telomeres, suggesting healthier ageing.
Instant coffee was associated with higher biological age acceleration scores and shorter telomeres, findings consistent with faster biological ageing.
Other brewing methods did not demonstrate consistent associations.
Researchers also observed that the associations remained largely unchanged even after accounting for factors such as smoking, body mass index (BMI), physical activity, alcohol consumption, milk or sugar added to coffee, and existing health conditions including diabetes and cardiovascular disease.
Why Might Filtered Coffee Be Different?
The study did not establish why filtered coffee appeared to be associated with healthier ageing. However, researchers proposed several possible explanations.
Filtered coffee contains hundreds of bioactive compounds, including:
Chlorogenic acids
Polyphenols
Caffeine
Antioxidants
These compounds have previously been associated with reduced inflammation, improved insulin sensitivity and better cardiovascular health.
The researchers also found that biomarkers such as cystatin C, basal metabolic rate (BMR) and glycoprotein acetylation (GlycA) statistically mediated part of the observed associations, suggesting inflammation and metabolic health may play a role.
Previous research has also shown that coffee’s health effects vary depending on brewing method. According to the European Society of Cardiology (ESC), unfiltered coffee contains higher levels of cafestol and kahweol, natural compounds that can raise LDL (“bad”) cholesterol when consumed in large amounts. Filter paper removes much of these diterpenes.
Does This Mean Instant Coffee Is Harmful?
Not necessarily. The researchers emphasised that the observed differences were relatively modest. Most estimates corresponded to only around 0.1 to 0.2 years of biological age acceleration, making the findings statistically significant but of uncertain clinical importance for individuals.
Moreover, observational studies cannot establish causation. People who choose filtered coffee may differ from instant coffee drinkers in many ways, including diet quality, socioeconomic status, sleep, exercise habits and healthcare access, that may not be fully captured despite statistical adjustments.
Coffee And Healthy Ageing: What Previous Research Says
Coffee has long been one of the world’s most studied beverages. According to the World Health Organization (WHO) and multiple large observational studies, moderate coffee consumption has generally been associated with lower risks of several chronic diseases, including type 2 diabetes and cardiovascular disease, although individual responses vary.
An umbrella review published in The BMJ concluded that consuming around three to four cups of coffee daily was generally associated with more health benefits than harms for most adults. However, excessive caffeine intake may worsen anxiety, interfere with sleep and may not be appropriate for pregnant women or people with certain heart rhythm disorders.
While the findings are intriguing, several limitations should be considered:
The study was cross-sectional, making it impossible to determine cause and effect
Coffee intake was self-reported, which may introduce recall bias
Most participants were of White European ancestry, limiting generalisability to other populations
Residual confounding cannot be ruled out despite extensive statistical adjustments
The study measured biological ageing markers rather than actual lifespan or disease outcomes
Researchers say long-term prospective studies and clinical trials are needed before recommending one brewing method over another solely for healthy ageing.
The new UK Biobank analysis suggests that filtered coffee may be associated with slower biological ageing, while instant coffee appears linked to less favourable ageing biomarkers.
However, the findings should be interpreted with caution because they demonstrate association, not causation. Until stronger evidence emerges, experts continue to recommend focusing on an overall healthy lifestyle that includes a balanced diet, regular physical activity, good sleep and avoiding tobacco, rather than relying on a single food or beverage to influence healthy ageing.
