Board Thread:General Discussion/@comment-75.133.22.18-20150921172853/@comment-2112031-20150921183525

I've heard a theory, don't know if it was ever stated in an interview or something, that Liquid's hair got bleached due to over-exposure to the sun.

This theory doesn't quite work on account of the fact that his hair wouldn't have stayed bleached permanently. Perhaps he liked the blond look so much that he decided to dye his hair from then onwards, who knows.

I believe it was said that Solid and Liquid (and Big Boss by extension) were originally intended to be naturally blond, with Solid and Naked Snake dyeing their hair brown in order to better fit with their environments during missions.

This was later retconned into them being naturally brown haired.