Study: Vitamin C may curb formation of cancer-linked chemicals in the stomach

Researchers at the University of Waterloo in Canada have used a mathematical model to suggest that vitamin C could help prevent potentially cancer-causing chemicals from forming during digestion. The question matters because exposure to nitrates and nitrites has risen in North American diets over recent decades, while studies linking these compounds to cancer have produced conflicting results. The work was published in the Journal of Theoretical Biology.

Why nitrates and nitrites are in question

Nitrates and nitrites are found in cured meats such as bacon and salami, and in fruits and vegetables grown in soil or water affected by pollution. They support important functions in the brain and cardiovascular system, but in the stomach they can take part in harmful reactions. One of them, nitrosation, can produce substances that researchers suspect may contribute to cancer development.

What the model showed

The team built a model simulating how nitrates and nitrites move through the body and change chemically. It covers the salivary glands, stomach, small intestine and plasma, the liquid part of blood. The simulations indicate that vitamin C consumed together with nitrates and nitrites can interfere with the formation of harmful compounds. That could explain why nitrate-containing foods do not always carry the same risk: leafy vegetables such as spinach naturally contain both nitrates and vitamin C.

The researchers also examined vitamin C supplements taken after meals. According to the model, taking vitamin C after each meal could moderately reduce the formation of nitrosation products, particularly when eating processed meats.

Limitations

The results come from mathematical simulations rather than clinical trials. Further research is needed to establish whether this leads to a measurable reduction in cancer risk in humans.

First author Dr. Gordon McNicol, a post-doctoral researcher in applied mathematics, said the presence of dietary vitamin C may help explain the inconsistencies in earlier research. Dr. Anita Layton, professor of applied mathematics and Canada 150 researcher chair, described the model as a roadmap for future studies, taking into account nitrite exposure, antioxidant intake, meal timing, gastric conditions and oral microbiome activity.