He was born in Burgos, Spain, son of Leeds-born Frankland Dent and his Spanish wife Carmen de Mira y Perceval. His father was the government Chemist in Singapore but his wife went home to Spain for the birth. The family later moved back to England and Charles was educated at Bedford School and Wimbledon College. In 1927 he left school to work in a bank but moved to work as a laboratory technician and study at evening classes at Regent Street Polytechnic. In 1930 he entered Imperial College London to study chemistry and graduated BSc. In 1934 he was awarded a PhD for his work on copper phthalocyanin (later marketed by ICI as 'Monastral blue') and went to work for ICI Dyestuffs Group in Manchester.
In 1937 he entered University College, London as a medical student. During WWII he saw war service in France and as a consultant in chemistry in the scientific department of British censorship (as a specialist in secret writing), including two years service in Bermuda and the USA. In 1944 he qualified in medicine and became house physician to Sir Thomas Lewis at University College. In 1945 he was appointed Assistant to the Medical Unit at University College Hospital Medical School under Sir Harold Himsworth and was sent to the recently liberated concentration camp at Belsen as part of the Medical Research Council study group to study the treatment of starvation by amino-acid mixtures.
In 1946-47 he studied in Rochester, New York on a Rockefeller scholarship, initially in the field of amino-acid metabolism. He was a pioneer in the field of partition chromatography for the study of biological fluids and developed methods of random testing for metobolic disorders. He also defined new amino-acid diseases such as various forms of Fanconi syndrome, Hartnup disease, argininosuccinic aciduria and homocystinuria.
In 1949 he awarded MD and in 1951 persuaded University College Hospital to establish a metabolic ward with beds, laboratories and outpatient clinics. He was appointed Reader in medicine. His research interests broadened to include the study of clinical disorders of calcium and phosphorus metabolism, vitamin D deficiency and the action of parathyroid, increasing the emphasis on the clinical side of his work, rather than laboratory science. In 1956 he was appointed Professor of Human Metabolism at UCH.
He died of leukaemia in 1976. He had married Margaret Ruth Coad in 1944; they had six children.