Coffee Slows The Clock For People Living With Severe Mental Illness

For some people living with psychosis or bipolar disorder, coffee may be more than a small daily comfort.

In a study of 436 adults in Norway with schizophrenia spectrum or affective disorders, researchers found that drinking up to three or four cups of coffee a day was linked to longer telomeres, tiny chromosome caps that track cellular ageing. The work, published in BMJ Mental Health, suggests that patients who stayed within the widely recommended caffeine limit had telomere lengths comparable to a biological age about five years younger than non coffee drinkers.

When Time Runs Faster In Severe Mental Illness

People with severe mental disorders already face a harsh arithmetic. On average, their lives are cut short by around 15 years compared with the general population, largely because of cardiovascular disease, cancer, and other conditions that usually rise with age. At the cellular level, many studies have reported shorter telomeres in schizophrenia and bipolar disorder, consistent with the idea that their bodies are ageing faster than the calendar suggests.

Telomeres sit on the ends of chromosomes and protect DNA during cell division. With each division they erode a little, and years of oxidative stress and inflammation can speed that loss. In the Norwegian Thematically Organised Psychosis (TOP) study, investigators had already shown shorter telomeres and reduced expression of the telomerase gene TERT in schizophrenia. This time, they asked a more everyday question that patients and clinicians can actually act on. How does something as ordinary as coffee fit into that biological story.

Participants, recruited from four psychiatric units in Oslo, were between 18 and 65, fluent in Norwegian, and free of conditions that would confound brain function. All had a diagnosis of schizophrenia spectrum or an affective disorder, including bipolar I, bipolar II, bipolar not otherwise specified, or major depressive disorder with psychosis. They gave blood samples so that white blood cell telomere length could be measured with quantitative real time PCR, and they sat through detailed interviews about symptoms, medication, tobacco use, and daily coffee habits.

Three To Four Cups, Then The Curve Bends Back

The team divided people into four groups by self reported coffee intake, from none to five or more cups a day. When they ran the statistics, adjusting for age, sex, ethnicity, smoking history, and psychotropic medication, the pattern that emerged was not a straight line. It was an inverted J shaped curve.

Those who drank no coffee had the shortest telomeres. Telomere length rose among people drinking one to two cups, peaked in the three to four cup group, then fell again in the heaviest coffee drinkers. The difference between non drinkers and those in the three to four cup range was statistically significant, and when the researchers translated base pair differences into years, it looked like roughly a five year gap in biological age.

Crucially, that apparent benefit did not keep climbing in the high intake group. People who reported five or more cups of coffee a day did not have significantly longer telomeres than abstainers, and they tended to be older and to have smoked for longer. Nearly eight in ten participants were smokers, and those in the 5 plus cup group had the longest smoking histories, underlining how tightly nicotine and caffeine use are intertwined in this population.

“Drinking a maximum of 3-4 cups of coffee a day may slow the biological ageing of people with severe mental illness, by lengthening their telomeres indicators of cellular ageing and giving them the equivalent of 5 extra biological years, compared with non-coffee drinkers, finds research published in the open access journal BMJ Mental Health.”

“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.”

A Familiar Drink, Complicated Biology

The study cannot prove that coffee itself slows telomere erosion in severe mental illness. It is cross sectional, with no healthy control group, and coffee intake was measured by a single self report question that did not capture cup size, brew method, or other sources of caffeine. The authors also lacked blood markers of inflammation and antioxidant status, and they relied on a mean telomere length measure rather than the number of critically short telomeres or additional ageing clocks.

Even so, the biology they sketch is plausible and uncomfortably relevant. Coffee carries a cocktail of bioactive compounds such as chlorogenic acid and trigonelline that have potent antioxidant and anti inflammatory properties. Experimental work suggests that caffeine rich beverages can activate the Nrf2 antioxidant pathway, damp down pro inflammatory cytokines, and influence the Akt GSK3 beta beta catenin signaling cascade that regulates TERT expression and telomere maintenance. At the same time, the paper points out, pushing intake beyond the widely recommended 400 milligram daily caffeine limit may flip those benefits, increasing reactive oxygen species, disrupting sleep, and aggravating anxiety or cardiovascular risk.

The message that emerges is not that people with severe mental disorders should start chasing telomere length with espresso, but that a very common habit might be part of a much broader ageing puzzle that clinicians already worry about. These patients smoke more, move less, and face heavy medication burdens and social disadvantage, all while their cells appear to be running ahead of the clock.

For now, the findings mostly argue for paying attention. In a group where high coffee consumption is already the norm, nudging intake back toward the three to four cup range could turn out to be a simple, acceptable way to line up lifestyle advice with the biology of ageing. The study does not tell us whether that change will actually add years to a life lived with schizophrenia or bipolar disorder, but it suggests that the question deserves serious, longitudinal answers.

Study: “Coffee intake is associated with telomere length in severe mental disorders,” BMJ Mental Health, 25 November 2025. DOI: 10.1136/bmjment-2025-301700.