Khalid bin Mohsen Shaari weighed 1,345 pounds in August when King Abdullah ordered him moved to Riyadh from the man's home in southern Saudi Arabia, CNN reported Monday.
Since losing half his body weight, Shaari has improved his lung and heart functions and has better muscle strength, said Dr. Ad-ed-al-Qahtani, head of the team overseeing Shaari's treatment.
Shaari, who is believed to be in his late teens, is now able to move his feet better but he still cannot move on his own, the doctor said. Shaari must use a mechanized pulley to sit in a custom-made wheelchair.
Doctors have dubbed Shaari "the smiling man" because he has consistently maintained his spirits during treatment.
Before beginning treatment, Shaari had reportedly not left his home in three years. A forklift was used to lift him out of his home so he could make the trip to Riyadh.