A new study from the University of Waterloo uses mathematical modeling to examine how vitamin C affects chemical reactions in the digestive system linked to cancer development.
In recent decades, North American diets have seen a steady increase in exposure to nitrates and nitrites: compounds found in deli meats, as well as fruits and vegetables grown with contaminated soil and water. While nitrates and nitrites play an important role in neurological and heart health, in the stomach, they can undergo a chemical reaction known as “nitrification” and form chemicals that many scientists suspect increase cancer risk.
Since at least the 1990s, researchers have been studying the relationship between cancer and these compounds, with conflicting results. Our work suggests that the presence of dietary vitamin C may help explain these inconsistencies.”
Dr. Gordon McNicol, postdoctoral researcher in applied mathematics and first author of the study
The team built a mathematical model of the salivary glands, stomach, small intestine and plasma and simulated how nitrites and nitrates move through the body and change over time. Their model showed that when vitamin C is also present in foods, such as leafy greens like spinach, which contain both vitamin C and nitrates, it could reduce cancer risk.
The study also suggested that taking vitamin C supplements after each meal could have a modest positive effect on reducing the formation of nitration products associated with cancer risk from dietary nitrites and nitrates, such as those found in foods such as bacon and salami.
The researchers hope these findings will inform future nutritional research.
“This work provides a mechanistic roadmap for future clinical and laboratory studies by identifying the key interacting factors of these potentially harmful chemical reactions, including nitrite exposure, antioxidant intake, meal timing, gastric states and oral microbiome activity,” said Dr. Anita Layton, professor of applied mathematics and Canada 150 chair researcher. “This model can help researchers design more targeted experiments and interventions, focusing on when and in whom nitrification is most likely to occur.”
The research, “Vitamin C as a Nitrification Inhibitor: A Modeling Study Between Dietary Patterns and Water Quality,” appears in Journal of Theoretical Biology.
