November 25, 2025

expert reaction to observational study looking at coffee consumption and biological ageing in individuals with severe mental disorders

An observational study published in BMJ Mental Health looks at coffee consumption and biological ageing in those with severe mental disorders.

Dr Elizabeth Akam, Senior Teaching Fellow in Biosciences, Loughborough University, said:

“The study by Mlakar et al. (2025) is an interesting body of work.

“It adds to emerging debate around the benefits of coffee and its associated bioactive compounds, including but not limited to caffeine and its metabolites _[1,2].

“A noteworthy limitation of this study is that it treats ‘coffee’ as if it were a single substance. However, coffee contains many different compounds, and we don’t know which of these were administered, in what doses, or how much actually ended up in the bloodstream.

“The evidence in this area is a mixed bag where many factors come into play like the efficacy of self-reporting – i.e. how accurately people report their coffee intake – and the blood concentration levels of the individual components of coffee, such as caffeine and associated metabolites. This matters because caffeine itself has been linked to telomere shortening. 

“The authors comment on possible antioxidant effects of bioactive compounds associated with coffee. Future studies that measure the antioxidant capacity of the blood as whole could provide more effective details in terms of aging and health benefits (e.g., telomere length).

“This in turn could also allow for the incorporation of confounders – factors that can influence study results –  such as the types of medication participants were taking; the level of antioxidant capacity provided by medications (for example, atypical v typical antipsychotics differ in antioxidant capacity _[3]; and how medications and coffee/caffeine might be broken down by the body in similar ways, such as through the same metabolic pathways (like cytochrome P450 enzymes _[4]).

“To truly establish a link, positive or negative, between coffee, caffeine and antioxidant capacity for telomere length, future research should consider leukocyte telomere length and the levels of different compounds in coffee – such as caffeine – in the blood.”

1- Tucker, L.A. Caffeine consumption and telomere length in men and women of the National Health and Nutrition Examination Survey (NHANES). Nutr Metab (Lond) 14, 10 (2017). https://doi.org/10.1186/s12986-017-0162-x

2 – Liu JJ, Crous-Bou M, Giovannucci E, De Vivo I. Coffee Consumption Is Positively Associated with Longer Leukocyte Telomere Length in the Nurses’ Health Study. J Nutr. 2016;146:1373–8.

3 – Sadowska-Bartosz I, Galiniak S, Bartosz G, Zuberek M, Grzelak A, Dietrich-Muszalska A. Antioxidant properties of atypical antipsychotic drugs used in the treatment of schizophrenia. Schizophr Res. 2016 Oct;176(2-3):245-251. doi: 10.1016/j.schres.2016.07.010. Epub 2016 Jul 20. PMID: 27449251.

4 – Carrascal-Laso L, Isidoro-García M, Ramos-Gallego I, Franco-Martín MA. Review: Influence of the CYP450 Genetic Variation on the Treatment of Psychotic Disorders. J Clin Med. 2021 Sep 21;10(18):4275. doi: 10.3390/jcm10184275. PMID: 34575384; PMCID: PMC8464829.

‘Coffee intake is associated with telomere length in severe mental disorders’ by Vid Mlakar et al. was published in BMJ Mental Health at 23:30 UK time on Tuesday 25 November. 

DOI: 10.1136/bmjment-2025-301700

Declared interests

Dr Elizabeth Akam: Dr Elizabeth Akam has previously been employed by AstraZeneca. Dr Akam has conducted caffeine CYP450 genotype analysis aligned to British Swimming and CYP450 variation studies in different global populations alongside telomere length studies aligned to sporting modalities.