Your body literally glows in the dark with visible light

Every living human body literally glows in the dark. Chemical reactions in our cells continuously produce metabolic byproducts that emit visible photons. In 2009, Japanese researchers used ultra-sensitive cryogenic cameras to film this human luminescence for the first time. The emitted light is roughly one thousand times weaker than human eyes can register, and it rises and falls throughout the day, peaking in the late afternoon when cellular activity is highest.

Sources

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