Nitrate and Human Health

Abstract

Nitrogen comprises 78 percent of the earth’s atmosphere and is necessary for life. Atmospheric nitrogen, via the environmental nitrogen cycle, is captured, or fixed, by symbiotic bacteria interacting with plants. Nitrates, thus, are intermediates in the movement of atmospheric nitrogen and also the food chain with dietary sources including red spinach, beetroot, and so forth. Although prevalent in the diet, nitrates have been viewed negatively because they chemically form carcinogenic nitrosamines in acidic environments, for example, the stomach. However, the recent discoveries of the vital gasotransmitter function of nitric oxide derived from nitrates and nitrites, endogenous production, and endogenous recycling in saliva have revealed the critical 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. Thus, dietary supplementation may represent an effective, inexpensive option for individuals with vascular disorders and a safe, efficacious means of enhancing performance in athletes. There remain, however, areas of needed research, such as elucidating the impact on anaerobic exercise, identifying interactions with other dietary components, determining efficacious, non-toxic doses, and optimal duration of supplementation. Thus, it is timely to revisit the nutritional and medicinal aspects of dietary nitrates on human health.