Caffeine Effect on Bone Metabolism in Rats: a Systematic Review

ABSTRACT

Abstract Caffeine is a highly-consumed substance around the world and can be found in various food sources and certain medications. The present systematic review aimed to evaluate the effect of caffeine on bone metabolism in rats. A systematic review was conducted in the PubMed, Medline, Scopus, Cocharane, Embase, and Clinical Trials.gov databases, and the Guidelines for Preferential Reporting for Systematic Reviews and Meta-Analyzes (PRISMA) were followed. In vivo experimental studies that presented caffeine as the study object were included, and studies which did not evaluate the bone metabolism and/or evaluated the caffeine in association with other substances were excluded. The quality evaluation of the selected studies was carried out following the guidelines of the Systematic Review Center for Laboratory Animal Experimentation (SYRCLE) and the Animal Research Reporting In Vivo Experiment (ARRIVE). Nine of the 472 initially identified articles met the inclusion criteria and were selected for qualitative evaluation. There was a variation between the included studies regarding the administered caffeine doses in each experimental group, as well as their frequency and duration of ingestion. Most studies show that caffeine can interfere with bone metabolism, be it in a negative way by accelerating bone loss and delaying bone repair, or in a beneficial way by activating osteogenesis and bone neoformation. There is a need for further studies to better understand the real effect of caffeine on bone metabolism.