Earth is more massive than Mars, so people on Martian soil would definitely suffer some health issues due to weaker gravity. Blood circulation is badly affected as heart muscles starts to deteriorate; as a result of the lower blood pressure, with less nutrients/oxygen to fuel our brain cells I reckon the neurons will be starved. For example astronauts on board the International Space Station(ISS) periodically perform intensive exercises with specially designed machines in order to keep their bodies fit; however this is not a long term solution and they will eventually return to Earth.
Will people on Mars be able to adapt and cope with the weak gravity? How can they prevent deterioration of their brain? Are there any drugs or prescriptions for these Martians or they will be staying in specialized quarters mimicking the conditions on Earth?