Potential protective effect of vitamin C on carcinogenesis caused by nitrosamine in drinking water: an experimental study on Wistar rats.

In an experiment with Wistar rats the question of whether oral vitamin C application has a protective effect in liver carcinogenesis caused by N-nitrosodiethylamine in drinking water (n = 104) was studied. When comparing four groups (without carcinogen, with carcinogen and carcinogen plus vitamin C alternately and concomitantly) significant statistical differences in the linear regression were noted. Ninety per cent of the rats developed hepatocellular carcinomas when only carcinogen was administered whereas the rate with additional administration of vitamin C alternately and concomitantly was 68% and 55%, respectively. Without carcinogen no tumour developed. The results suggest that vitamin C may delay the development of liver cancer upon oral administration of N-nitrosodiethylamine. The explanation for this fact is still hypothetical.