Coffee intake is associated with telomere length in severe mental disorders

Objective Telomere length is an indicator of cellular ageing, with patients with severe mental disorders tending to have shorter telomeres than the general population. Coffee consumption may reduce oxidative stress, helping prevent biological ageing processes like telomeric shortening. The British National Health Service (NHS) advises limiting caffeine intake to 400 mg/day (4 cups of coffee). However, the role of coffee consumption and telomere length in psychiatric populations remains unclear.

This cross-sectional study included 436 participants (schizophrenia spectrum [n = 259] and affective disorders [n = 177]) from the Norwegian TOP study. Leukocyte telomere length (TL) was measured via blood using quantitative real-time Polymerase Chain Reaction (qPCR). Patients self-reported coffee consumption, quantified as cups per day (no coffee, 1-2, 3-4, 5+).

An inverted J-shape was found between TL and coffee intake, peaking at 3-4 cups/day before declining after 4 cups (F = 3.29, p = .02). The largest TL difference was between those drinking the highest recommended dose and non-drinkers (F = 6.13, p = .01). Coffee drinkers within the recommended dose had longer TL, comparable to five years younger biological age, adjusted for confounders.

Coffee intake within the recommended dose is linked to longer telomeres in severe mental disorders, comparable to five years younger biological age. What is already known on this topic? Patients with severe mental disorders tend to have shorter telomere lengths, an indicator of accelerated cellular ageing. Coffee consumption has been noted to possess health benefits, which may help prevent telomere shortening. The relationship between coffee consumption and telomere length in psychiatric populations remains unclear. What this study adds? Coffee consumption up to 3-4 cups per day, but not exceeding this amount, was associated with longer telomeres in patients with severe mental disorders. Patients consuming up to 4 cups of coffee per day had telomere lengths comparable to a biological age five years younger than non-coffee drinkers. How this study might affect research, practice or policy? Our study suggests the importance of further research investigating the role of coffee consumption in biological ageing. Competing Interest Statement The authors have declared no competing interest. Funding Statement This study was funded by the Research Council of Norway (#223273), the KG Jebsen Stiftelsen, and the MRC fellowship to MA (#MR/W027720/1). Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This study was approved by the Regional Committee for Medical Research Ethics (South-Eastern Norwegian Health Authority) and the Norwegian Data Inspectorate (Code: 2009/2485/REK sor-ost). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Data Availability All data relevant to the study are included in the article or uploaded as supplementary information.