Humans naturally glow in visible light

Every living human body emits ultra-weak visible light, peaking in the late afternoon. This phenomenon, known as biophoton emission, is roughly one thousand times weaker than the sensitivity threshold of the naked human eye. Highly sensitive cryogenic cameras revealed that metabolic reactions involving free radicals constantly release photons, creating a subtle biological glow that fluctuates throughout our circadian cycle.

Sources

• Imaging of Ultraweak Spontaneous Photon Emission from Human Body Displaying Diurnal Rhythmjournals.plos.org ↗
• BiophotonWikipedia ↗