It is rare to have glowing eyes as glowing eyes in humans is not a normal occurrence.
Glowing eyes in humans is often a result of the flash of a camera or certain medical conditions and not a biological ability to produce light.
The eyes glowing and appearing red or white as a glow is caused by the reflection of the flash off the retina or blood vessels that are in the eye.
In rare cases glowing eyes also known as a glowing iris can be a symptom of pigment dispersion syndrome which is a condition in which pigment flakes off the iris and causes light to shine through.
Also a white reflex in the eye, which is also called leukocoria can also be a sign of retinoblastoma which is a rare form of eye cancer.
Human eyes do also appear to glow in a night vision camera although the human eyes glowing in a night vision camera is not a true glow of the eyes.
While human eyes do appear to glow in a night vision camera, the eyes glowing in the night vision camera is not in the same way that animals with a tapetum lucidum glow.
In night vision the human eyes glowing is due to the reflection of the infrared light which is often from the infrared illuminator's on the night vision camera which reflects off the choroid, which is a layer of blood vessels that are behind the eyes retina.
Human eyes lack the reflective tapetum lucidum that is found in many types of nocturnal animals, but human eyes still reflect some light and most particularly when you use IR or infrared illumination.
Night vision cameras often use either active IR or infrared illumination or passive IR infrared illumination to see in the dark.
And many types of night vision cameras also have infrared LEDs which emit invisible light to illuminate the scene.
The infrared light is reflected off of objects, which also include the human eye and the light then also reflects off of the choroid which is the layer that is behind your retina, that causes a visible reflection, which in turn appears as a glow in the night vision cameras glow.
The effect of the human eye glowing in a night vision camera is different from the eyeshine which is seen in nocturnal animals like deer or cats that have tapetum lucidum which reflects much more light.
The reflection from our human eyes is much weaker than the reflection of the nocturnal animals eyes due to us humans lacking the tapetum lucidum.
The red eye effect in a regular flash camera is also a result of the reflection off of the blood vessels in the choroid.