What causes glowies to glow?

[SandyCat]

Do they put extra fluoride in their water?

 

[Gog & Magog]

Jellyfish gene therapy.

 

[Vingle]

I assume the term stems from when it was all the rage to use radioactive materials for even ingesting and beauty-purposes. The feds obviously tried to hide the fact people were slowly killing themself.

 

[Sexy Senior Citizen]

A high-phosphorus diet.

 

[TheRetardKing]

If you snap their bones, they'll glow in the dark.

 

[ToroidalBoat]

UV (like from a blacklight) illuminating natural fluorescent pigment?

 

[Chocolate Wombat]

It's solar radiation from flying around in recovered UFOs.

 

[ThicClaw]

 

[Alligator Alcatraz]

The term "glow" is a reference to the way bioluminiscence functions: shining in darkness, lacking camoflage to hide one's presence. Three letter agencies glow in the dark because the common man can tell when a glowie is acting in an unnatural manner.

 

[Rozzy]

It's the tritium milkshakes that cause them to glow.

 

[AbduluCthuluZulu]

Same thing that makes the red man red.

 

[ditto]

Reptilian blood.

 

[AverageQuarianEnjoyer]

God helpfully highlighting our targets