Acute exogenous ketone monoester supplementation decreases cardiac vagal modulation in a dose-dependent manner

Thiessen, J. S.; Rourke, A. J.; Pocchi, G. C.; Yong, C. M.; Odisho, A. R.; Nash, J. A.; Underwood, A.; Yacoub, R.; Millar, P. J.; Walsh, J. J.

doi:10.1101/2025.09.19.677373

bioRxiv · 10.1101/2025.09.19.677373

Acute exogenous ketone monoester supplementation decreases cardiac vagal modulation in a dose-dependent manner

Thiessen, J. S.·Rourke, A. J.·Pocchi, G. C.·Yong, C. M.·Odisho, A. R.·Nash, J. A.·Underwood, A.·Yacoub, R.·Millar, P. J.·Walsh, J. J.

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Abstract

Exogenous ketone supplementation can elevate heart rate (HR) but the effects on cardiac autonomic modulation remain unclear. HR variability was analyzed from 18 healthy adults (23 {+/-} 3 yrs; n=10 females) ingesting 0.3 (low-dose) or 0.6 g/kg (high-dose) ketone monoester or placebo in a randomized crossover, double-blind design. Compared to placebo, both ketone doses increased capillary {beta}-hydroxybutyrate and reduced the percentage of successive R-R intervals that differ by [≥]50-ms (pRR50) and the root mean square of successive differences (RMSSD) at 45- and 120-min post-ingestion (all p<0.05). Acute ketone ingestion decreases HR variability measures associated with reduced cardiac vagal modulation.

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Thiessen, J. S., Rourke, A. J., Pocchi, G. C., Yong, C. M., Odisho, A. R., Nash, J. A., Underwood, A., Yacoub, R., Millar, P. J., Walsh, J. J.. 2025-09-21. Acute exogenous ketone monoester supplementation decreases cardiac vagal modulation in a dose-dependent manner. https://doi.org/10.1101/2025.09.19.677373

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