Moderate coffee consumption may slow down cellular aging in people with severe mental disorders.

Research indicates that drinking up to four cups of coffee a day can help preserve telomere length in individuals with serious mental illnesses, which is associated with a “younger” biological profile. However, exceeding this amount not only fails to provide additional benefits but may also accelerate cellular stress.

The Impact of Coffee on Biological Aging

Consuming 3–4 cups of coffee daily is linked to slower biological aging in people with severe mental disorders. According to data published in BMJ Mental Health, such individuals had longer telomeres—sections of DNA at the ends of chromosomes that serve as markers of cellular aging—compared to those who did not drink coffee. This difference may correspond to about five biological years.

However, the study did not find similar benefits for those who consumed more than four cups of coffee per day. This level matches the maximum daily intake recommended by leading medical organizations, including the NHS and FDA.

What Are Telomeres and Why Are They Important?

Telomeres are located at the ends of chromosomes and serve a protective function, preventing the wear and tear of genetic material, much like plastic tips on shoelaces. As we age, telomeres naturally shorten, but this process occurs more rapidly in people with mental disorders such as psychosis, schizophrenia, and bipolar disorder. Since telomeres are sensitive to external factors, including diet, researchers set out to determine whether moderate coffee consumption could slow their shortening in this patient group.

Study Design and Participant Habits

The study involved 436 adults who participated in the Norwegian TOP psychosis study from 2007 to 2018. Of these, 259 had schizophrenia and 177 had affective disorders, including bipolar disorder and severe depression with psychosis. Participants reported their daily coffee intake and were divided into four groups: non-coffee drinkers, those who drank 1–2 cups, 3–4 cups (110 people), and 5 or more cups per day. Smoking habits and duration were also considered.

Those who drank 5 or more cups of coffee daily were generally older and had a longer history of smoking. On average, participants with schizophrenia consumed more coffee than those with affective disorders. About 77% of all participants were smokers, with an average smoking history of 9 years.

Telomere Measurements and Key Findings

Telomere length was measured in leukocytes from blood samples. Results showed that participants who drank 3–4 cups of coffee per day had longer telomeres than those who did not drink coffee, forming a so-called J-shaped curve. No such association was observed in the group drinking 5 or more cups. The analysis accounted for age, sex, ethnicity, smoking, type of mental disorder, and current therapy.

Biological Explanations and Study Limitations

The authors emphasize that the study is observational and cannot establish a direct causal relationship. There was also no data on the type of coffee, timing of consumption, exact caffeine content, or intake of other caffeinated beverages.

Nevertheless, the researchers note that coffee contains powerful antioxidant and anti-inflammatory compounds that may protect cells from age-related damage. Telomeres are particularly sensitive to oxidative stress and inflammation, which may explain the potential benefits of coffee for people prone to accelerated aging.

Global Coffee Consumption and Safety Considerations

Coffee remains one of the most popular beverages worldwide: in 2021–2022, about 10.56 billion kilograms of coffee were consumed. Despite its potential benefits, scientists warn that exceeding the recommended daily caffeine dose (400 mg, roughly equivalent to four cups of coffee) can lead to cell damage and faster telomere shortening due to the formation of reactive oxygen species. International health organizations advise limiting daily caffeine intake to 400 mg or less.