Nitrate Ingestion: A Review of the Health and Physical Performance Effects

This paper provides an overview of the current literature and scientific evidence surrounding inorganic nitrate (NO(3)(−)) supplementation and its potential for improving human health and physical performance. As indicative of the ever-expanding organic and natural food consumer market, athletes and health enthusiasts alike are constantly searching for ingredient-specific “super foods” and dietary supplements capable of eliciting health and performance benefits. Evidence suggests that NO(3)(−) is the viable active component within beetroot juice (BRJ) and other vegetables, responsible for health-promoting and ergogenic effects. Indeed, multiple studies support NO(3)(−) supplementation as an effective method to improve exercise performance. NO(3)(−) supplementation (either as BRJ or sodium nitrate [NaNO(3)(−)]) has also demonstrated modest benefits pertaining to cardiovascular health, such as reducing blood pressure (BP), enhancing blood flow, and elevating the driving pressure of O(2) in the microcirculation to areas of hypoxia or exercising tissue. These findings are important to cardiovascular medicine/exercise physiology and suggest a possible role for NO(3)(−) supplementation: (1) as a low-cost prevention and treatment intervention for patients suffering from blood flow disorders; and (2) an effective, natural ergogenic aid for athletes. Benefits have been noted following a single bolus, as well as daily supplementation of NO(3)(−). While results are promising, additional research is needed to determine the impact of NO(3)(−) supplementation on anaerobic exercise performance, to identify principle relationships between isolated nitrate and other ingredients found in nitrate-rich vegetables (e.g., vitamin C, polyphenols, fatty acids, thiocyanate), to explore the specific dose-response relationships needed to elicit health and ergogenic benefits, to prolong the supplementation period beyond a relatively short period (i.e., >15 days), to determine if more robust effects can be observed with longer-term treatment, and to fully examine the safety of chronic NO(3)(−) supplementation, as this continues to be a concern of some.