Mid-infrared light produces anti-ageing effects through resonant absorption by living organisms

Abstract

Ageing is commonly viewed as a consequence of cumulative molecular damage and declining stress resilience. However, this perspective overlooks the possibility that ageing may primarily arise from an efficiency loss of integrated cellular operation. Here, we show that ageing can be systemically prevented by enhancing cellular efficiency using frequency-specific mid-infrared (MIR) light, as revealed by multiscale (organismal-, cellular- and molecular-level) analyses of Caenorhabditis elegans. Remarkably, super-weak 34-THz MIR light (~1 W mm-2) prolonged the median lifespan of worms by 60%, delaying ageing onset and preventing abrupt "cliff-edge" mortality, without detectable thermal effects. At the cellular level, MIR exposure enhanced global gene transcription in parallel with the establishment of a mitochondrial state of high-efficiency energy metabolism, together preserving youthful cellular homoeostasis during ageing. These cellular effects were associated with vibrational modes of phosphate groups (PO4) in nucleic acids and mitochondrial phospholipids within the 33-35 THz range, providing a frequency-matched molecular context for MIR modulation. Together, our results support an efficiency-first, systemic anti-ageing model in which frequency-specific MIR light resonantly enhances the integrated kinetic efficiency of cellular systems, spanning gene transcriptional dynamics and mitochondrial bioenergetic flux, rather than the activation of damage-repair or stress-response pathways. These findings advance our understanding of MIR light-matter interactions in living systems and establish a non-biochemical, physical strategy for modulating ageing.