Just as the idea evolved, I learned that Professor Linus Pauling had stated that vitamin C might be helpful for cancer patients. My first reaction was one of dismay, even defeat, but such a feeling did not last very long. I wrote immediately to Dr. Pauling and we have been close collaborators ever since. Dr. Pauling had reasoned that an adequacy of vitamin C (necessary for collagen formation) might increase the scirrhous reaction and help encapsulate tumors (8). On further reading we realized that vitamin C was involved in many other aspects of host resistance, such as cell-mediated immunity and the biosynthesis of interferon (9, 10). Many independent investigators subsequently were able to show that ascorbate administered in the gram range enhanced these defensive mechanisms to levels of activity far above the so-called normal range (11-15). Therefore, there is a strong case for the expectation that supplemental vitamin C, in adequate dosage, might have some beneficial effect against cancer.