Dietary Nitrate, Nitric Oxide, and Cardiovascular Health

Abstract

Emerging evidence strongly suggests that dietary nitrate, derived in the diet primarily from vegetables, could contribute to cardiovascular health via effects on nitric oxide (NO) status. NO plays an essential role in cardiovascular health. It is produced via the classical L-arginine-NO-synthase pathway and the recently discovered enterosalivary nitrate-nitrite-NO pathway. The discovery of this alternate pathway has highlighted dietary nitrate as a candidate for the cardioprotective effect of a diet rich in fruit and vegetables. Clinical trials with dietary nitrate have observed improvements in blood pressure, endothelial function, ischemia-reperfusion injury, arterial stiffness, platelet function, and exercise performance with a concomitant augmentation of markers of NO status. While these results are indicative of cardiovascular benefits with dietary nitrate intake, there is still a lingering concern about nitrate in relation to methemoglobinemia, cancer, and cardiovascular disease. It is the purpose of this review to present an overview of NO and its critical role in cardiovascular health; to detail the observed vascular benefits of dietary nitrate intake through effects on NO status as well as to discuss the controversy surrounding the possible toxic effects of nitrate.

Cruciferous and Allium Vegetable Intakes are Inversely Associated With 15‐Year Atherosclerotic Vascular Disease Deaths in Older Adult Women

“…Leafy green vegetables are a rich source of dietary nitrate that can be reduced to NO via the entero‐salivary nitrate‐nitrite‐NO pathway . Although significant in the unadjusted analysis, after adjustment for covariates and especially after further adjustment of intake of nonleafy green vegetables, which included allium and cruciferous vegetables, the beneficial effect disappeared.…”

Association of dietary nitrate with atherosclerotic vascular disease mortality: a prospective cohort study of older adult women

“…There is a need to determine whether these improvements in risk factors can translate into improved long-term 4 Measured in 1215 participants. 5 Measured in 1106 participants. 6 Measured in 895 participants.…”

“…Through this pathway, NO is generated via the sequential reduction of the anions nitrate and nitrite by the facultative anaerobic bacteria on the dorsal surface of the tongue, the acidic environment of the stomach, and a number of endogenous molecules identified as having nitritereducing potential (5). This nitrate-nitrite-NO pathway is independent of NO synthase (NOS) and may be enhanced in instances of hypoxia (6).…”

Beetroot and Sodium Nitrate Ameliorate Cardiometabolic Changes in Diet‐Induced Obese Hypertensive Rats

“…Endogenous NO produced by NO synthase in endothelial cells mediates vascular dilation and inhibits infiltration of inflammatory cells and platelet aggregation . Increased consumption of inorganic nitrate in green leafy vegetables and beetroot have potential cardiovascular benefits . Recently, a meta‐analysis and several clinical studies have suggested that dietary inorganic nitrate or beetroot juice reduced plasma LDL, and systolic blood pressure, with improved endothelial and cardiac function …”