A new study in *Scientific Reports* finds that standard LED lighting (350-650nm) undermines human visual performance. Researchers at University College London tested color contrast sensitivity in an LED-lit environment, showing that mitochondrial respiration is suppressed by the blue wavelengths dominant in LEDs.

The negative effects stem from LEDs' limited spectrum, which lacks the longer wavelengths (700nm+) found in sunlight and incandescent bulbs. These longer wavelengths boost mitochondrial ATP production, improving metabolism and function. Supplementing LEDs with broad-spectrum light (400-1500nm+) for two weeks reversed these deficits.

Improvements in contrast sensitivity lasted for two months after the supplemental lighting was removed. The study suggests systemic health impacts, particularly for the elderly or clinical settings. Changing lighting could be a cost-effective public health intervention, moving beyond visual efficiency to consider physiological needs.