Ioannis Kalaitzis was born in Kallipoli, Piraeus and after successful examinations he was admitted to the Medical School of Patras where he received a medical degree. After completing his medical service for the rural population, he specialized in General Surgery at the 1st Surgical Clinic of the Tzaneio General Hospital of Piraeus. At the same time, he actively participated in the scientific program of the 2nd University Clinic of Surgery at Aretaion Hospital, where he completed the Ph.D. thesis entitled "Effects of endoscopic sphincterotomy on the biliary epithelium. A case-control study''. He then specialized in advanced Laparoscopic Surgery at San Giovanni Battista Hospital-Molinette, in Torino, Italy, under the supervision of the Honourable Professor of Surgery, Mario Morino. He then worked as a specialist consultant at Spire Yale Hospital in the UK where he specialized in laparoscopic abdominal wall reconstruction techniques.
Since 2013 he has been working as a private General Surgeon performing numerous surgical procedures. He participates in the 4th Surgical Clinic of Errikos Dynan Hospital Centre, where he also served as General Surgeon Attending. He maintains the position of General Surgeon at ALPHALIFE's Private Multiclinics of ALPHABANK and of Medical Director at Total Care Network. He has published numerous scientific papers in foreign language journals. Recently, he has begun working with the exemplary Yoda Day Care Unit, where he performs numerous specialized procedures with particular emphasis on the use of new laser applications in common diseases such as pilonidal cyst and haemorrhoids.