One of former president Jacob Zuma's sons, Edward Zuma, says his father is overworked and has been instructed by doctors to rest. Speaking to News24, Zuma junior said: "Like any other person of his age, he had to go to the doctors for a check-up."He is out of hospital, but has been instructed to rest because doctors say he is overworking himself. He doesn't get enough rest and for his age that is not allowed," Edward said on Saturday afternoon. On Friday, iOL reported that the Jacob Zuma Foundation had confirmed that Zuma had been hospitalised for a week, before being discharged on Thursday, the same day the KwaZulu-Natal High Court in Pietermaritzburg denied his appeal against an earlier defamation judgment.Judge Dhaya Pillay, who found that Zuma had defamed fellow ANC veteran Derek Hanekom when he tweeted that the former tourism minister was a "known enemy agent", dismissed the former president's appeal bid.The exact reason for his hospitalisation, however, is unknown. On Saturday afternoon, Zuma took to Twitter to thank his supporters for their well wishes.He tweeted: "Your messages have been overwhelming during this difficult time."Thank you all for the well wishes. Your messages have been overwhelming during this difficult time.— Jacob G Zuma (@PresJGZuma) November 9, 2019 Zuma was due to appear before the commission of inquiry into state capture next week, but pulled out soon after his appearance was announced, citing health problems.The foundation said Zuma's return to the commission would be made public at a later stage, iOL reported.