Research published on December 4, 2025, in the BMJ Mental Health journal suggests that consuming up to four cups of coffee daily may slow biological aging in individuals with severe mental illnesses. The study found a correlation between coffee intake and longer telomeres, cellular markers that indicate aging. Specifically, those drinking this amount of coffee may experience a biological aging delay equivalent to approximately five years compared to non-coffee drinkers.
The study involved 436 adults with major psychiatric disorders, including schizophrenia and bipolar disorder, who participated in the Norwegian Thematically Organised Psychosis (TOP) study from 2007 to 2018. Participants reported their daily coffee consumption and were categorized into four groups based on their intake: none, 1-2 cups, 3-4 cups, and 5 or more cups. Notably, individuals consuming five or more cups did not show the same benefits and may even experience detrimental effects.
Understanding Telomeres and Their Importance
Telomeres are the protective caps at the ends of chromosomes, analogous to the plastic tips on shoelaces that prevent fraying. As people age, telomeres naturally shorten, a process that appears to accelerate in those with serious psychiatric conditions. The researchers aimed to determine if moderate coffee consumption could slow this shortening. Previous studies have linked coffee to various health benefits, making it a logical subject for investigation in this context.
Participants in the study reported differing coffee habits, with approximately 77% identifying as smokers, which influences how caffeine is metabolized. Those consuming five or more cups tended to be older and had a longer smoking history compared to those drinking less coffee.
Key Findings and Implications
The research team measured telomere length in participants using white blood cells from blood samples. The results illustrated significant differences among the coffee consumption groups, forming a J-shaped curve. Participants consuming 3-4 cups of coffee per day exhibited longer telomeres than non-coffee drinkers, with telomere lengths suggesting a biological age around five years younger for this group.
Researchers emphasized that while the findings are promising, the study is observational and cannot definitively establish causation. There were also limitations regarding the specifics of coffee consumption, such as type and timing, as well as the caffeine content and other caffeinated beverages consumed.
The potential mechanisms behind the observed effects may relate to coffee’s rich content of antioxidants and anti-inflammatory compounds. These components could help protect cells from damage linked to aging, particularly in individuals whose conditions may predispose them to accelerated aging.
While coffee remains a popular beverage globally, with an estimated 10.56 billion kilograms consumed in 2021-2022, the researchers caution against excessive intake. They reiterated recommendations from health authorities, advising individuals to keep caffeine consumption at or below 400 mg per day, which is roughly equivalent to four cups of coffee. Excessive consumption may lead to cellular damage and telomere shortening.
This study contributes valuable insights into the intersection of diet and mental health, suggesting that moderate coffee consumption may offer protective benefits for those with severe mental illnesses. Further research is necessary to explore the complexities of coffee’s effects on biological aging and mental health.
