Basil Davidson in a tv series in the 1980's showed temple drawings of egyptians coloured in red for the men yellow for the women.
He said this must be the colour of the ancient egyptians,then without realising what he had said he then whent on to show the life of the people of the nuba mountains and said that they are the link with ancient egypt and their women danced at the courts of the pharoahs, and the men where part the elite gaurd that protected the pharoahs and the pyramids.
The famous NUBA wrestlers in africa paint themselves red when wrestling and the women when dancing cover themselves in their complementary colors.
So the colouration of the skin ot the ancient egyptians was for symbolic purposes only.