I have seen some anecdotal comments about this but have not seen what some feel works work for me. As a rule when working outside I wear light colors that tend to reflect sunlight which helps, somewhat, keep me cooler then darker colors will. But insects fly near by but whether that is to see if I'm a potential food source or what I cannot be sure. Some insects are attracted by odor, not color, so clothing color would make no difference to mosquitoes which are drawn by the CO2 you exhale.