Not just a lost cause but DANGEROUS. Esp those born in 0-G BUT you have hope. Those living in orbital colonies can be in Torus type colonies that rotate to simulate 1G. A hard science way of achieving artificial gravity.
Well for starters, the first thing to suffer is the skeletal system. Humans are adapted to our usual 1G pulling down on us and this affects bone development. Next would be blood pressure but for that, its gonna take awhile. Also your heart adapts to the grav.
Which is why my Martian Soldiers...