A new study in BMJ Mental Health suggests that drinking a moderate amount of coffee may be linked to slower biological aging in people living with major psychiatric disorders. The research found that participants who drank three to four cups a day had longer telomeres, a marker used to study cellular aging, compared with people who drank no coffee.
Telomeres are caps on the ends of chromosomes that help protect DNA. They naturally shorten over time, and studies have shown that people with conditions such as schizophrenia, bipolar disorder and psychotic depression often have shorter telomeres than those without these illnesses. Researchers say diet and lifestyle may influence how quickly telomeres shorten.
“Telomeres are highly sensitive to both oxidative stress and inflammation, further highlighting how coffee intake could help preserve cellular ageing in a population whose pathophysiology may be predisposing them to an accelerated rate of ageing,” the study authors wrote.
The study followed 436 adults in Norway with schizophrenia or affective disorders. Participants reported how many cups of coffee they drank per day and provided blood samples so researchers could measure telomere length. Most participants also smoked cigarettes, which can affect caffeine metabolism and influence telomere biology, and the analysis adjusted for smoking and other health factors.
The results formed a J-shaped pattern. Compared with people who drank no coffee, those who drank three to four cups had longer telomeres, equivalent to what the researchers describe as about five “biological years.” People who drank five or more cups did not show this benefit.
Because the study was observational, it cannot prove that coffee slows cellular aging. The researchers also did not have details about the type of coffee consumed, brewing method or caffeine content. But they note that coffee contains antioxidant and anti-inflammatory compounds that may help explain the pattern they observed.
The authors caution that drinking more than four cups a day is not recommended. Several health agencies, including the U.S. Food and Drug Administration, advise limiting caffeine intake to about 400 milligrams per day.
The study adds to ongoing research on how diet and lifestyle influence aging biology, particularly for people with chronic mental health conditions. More work is needed to understand whether these associations hold true over time and whether coffee directly affects telomere maintenance.
This research was funded by the UK Medical Research Council, the Research Council of Norway and the KG Jebsen Foundation.