By colonizing the moon humans would be expanding their knowledge and also their horizons so that they can learn more and be better prepared. I also believe that colonizing the moon will help to keep human existence alive. If a drastic event happened on the earth the humans on the moon would still be able to survive and flourish.
Colonization on the moon would lead to the first space warfare because of the countries tension about who gets what. Also, children born on the moon have been seen to have deformities more often. There are also hazardous dust storms that are terrible for human health. It is just impractical to colonize o the moon.
Colonizing the moon isn't healthy for humans because it takes funding away from feeding, clothing and housing those people who need basic things to live on Earth. In terms of permanent moon colonies, bones and muscles on normal human bodies will atrophy from a lower gravitational field on the moon and the physiological systems in humans will alter.