Dietary Nitrate: Friend or Foe

As food additives, nitrites (E249, E250) and nitrates (E251, E252) are essential to produce high-quality processed meat products, contributing to the formation of pink colour and flavour, and efficiently inhibiting the growth of Clostridium botulinum. However, they have a “well-accepted” bad reputation even though their usage amount in processed meat products is very low. They can potentially react with amines to form genotoxic and carcinogenic N-nitroso compounds, and therefore are linked to the negative health outcomes (e.g., cancer development) of processed meat consumption. In contrast, a large number of recent studies reported that dietary nitrate, from vegetables in particular, has shown beneficial health impacts, including ergogenic effects on exercise performance, benefiting cardiovascular health, and reducing the risk of diabetes and dementia. As a result, despite the controversy, studies have tried to replace inorganic nitrate salts with “natural” nitrate extracts from vegetables such as beetroot and spinach. In addition, high nitrate-containing beetroot supplements are commercially promoted.

This Research Topic aims to explore the two distinct potential roles of dietary nitrate and nitrite in human health: as a friend or foe. We encourage a comprehensive, evidence-based discussion about the health implications of dietary nitrate and nitrite from different sources to inform practice and policy. Therefore, Original Research (experimental and observational), Methods, Meta-Analyses, Systematic or Scoping Reviews, Perspective, General Commentary, Opinion and Clinical Trials are welcomed. This Topic will also welcome laboratory studies that develop key tools in nitrate and nitrite-related research (e.g., nitrate and nitrite food composition database, validated biomarkers, novel analytic methods to quantify nitrate/nitrite/nitric oxide/nitrosamines content in food and drinks, and biological samples).

Subtopics of interest in this context include (but are not limited to):
• Dietary nitrate and nitrite intake in the population.
• Health impacts of dietary nitrate and nitrite in varying contexts, including exercise performance, cardiovascular and brain health, diabetes, and oral and gut microbiome.
• The impacts of co-existing compounds (e.g., dietary fibre, vitamin C, phytochemicals) on the roles of dietary nitrate and nitrite in human health.
• Endogenous nitrosamine formation after dietary nitrate and nitrite ingestion from different sources (water vs processed meat products vs vegetables).
• The fate of dietary nitrate and nitrite from different sources (water vs processed meat products vs vegetables) in the human gastrointestinal tract.