Dietary Nitrates, Nitrites, and Food Safety: Risks Versus Benefits
Keith R Martin*
Center for Nutraceutical and Dietary Supplement Research, College of Health Sciences, University of Memphis, Memphis, USA
*Corresponding Author: Keith R Martin, Center for Nutraceutical and Dietary Supplement Research, College of Health Sciences, University of Memphis, Memphis, USA.
April 08, 2021; Published: May 26, 2021
Atmospheric nitrogen, via the environmental nitrogen cycle, is captured, or fixed, by symbiotic bacteria interacting with plants. Nitrates, as a result, are intermediates in the movement of atmospheric nitrogen into the food chain with rich dietary sources including red spinach, beetroot, etc. Nitrate-rich fertilizers may further increase nitrogen content of plants. Other sources include potable water, dietary supplements and food additives. Although prevalent in the diet, nitrates have been viewed negatively because they chemically form carcinogenic nitrosamines in acidic environments, e.g. stomach, purportedly leading to gastric cancer as well as neoplasia of the intestine, brain, pancreas, and contributing to Non-Hodgkin’s lymphoma. Other reports indicate associations with hyperthyroidism and diabetes mellitus. A second major concern with dietary nitrate consumption is the development of methemoglobinemia particularly in infants caused by increases in methemoglobin where heme iron is oxidized to ferric iron and unable to bind and transport oxygen. In contrast, the recent discoveries of the vital gasotransmitter function of nitric oxide derived from dietary nitrates and nitrites, endogenous production, and endogenous recycling and considerable concentration in saliva have revealed the importance of nitrates to health including improved cardiovascular function (reductions in blood pressure), improved cognition, reduced platelet aggregation, and enhanced blood flow to ischemic (hypoxic) and/or exercising tissues. As a result, dietary supplementation may represent an effective, inexpensive option for individuals with vascular disorders and a safe, efficacious means of enhancing performance in both recreational and competitive athletes. Given the myriad beneficial effects tempered by the purported negative effects, it is timely to revisit the conundrum of risk versus benefit from dietary nitrates.
Keywords:Dietary Nitrates; Food Safety; Soil Quality
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