Pauling's work on vitamin C in his later years generated much controversy. He was first introduced to the concept of high-dose vitamin C by biochemist Irwin Stone in 1966. After becoming convinced of its worth, Pauling took 3 grams of vitamin C every day to prevent colds. Excited by his own perceived results, he researched the clinical literature and published "Vitamin C and the Common Cold" in 1970. He began a long clinical collaboration with the British cancer surgeon Ewan Cameron in 1971 on the use of intravenous and oral vitamin C as cancer therapy for terminal patients. Cameron and Pauling wrote many technical papers and a popular book, "Cancer and Vitamin C", that discussed their observations. Pauling made vitamin C popular with the public and eventually published two studies of a group of 100 allegedly terminal patients that claimed vitamin C increased survival by as much as four times compared to untreated patients.