Vascular effects of dietary nitrate (as found in green leafy vegetables and beetroot) via the nitrate‐nitrite‐nitric oxide pathway

Abstract

The discovery that dietary (inorganic) nitrate has important vascular effects came from the relatively recent realization of the 'nitrate-nitrite-nitric oxide (NO) pathway' . Dietary nitrate has been demonstrated to have a range of beneficial vascular effects, including reducing blood pressure, inhibiting platelet aggregation, preserving or improving endothelial dysfunction, enhancing exercise performance in healthy individuals and patients with peripheral arterial disease. Pre-clinical studies with nitrate or nitrite also show the potential to protect against ischaemia-reperfusion injury and reduce arterial stiffness, inflammation and intimal thickness. However, there is a need for good evidence for hard endpoints beyond epidemiological studies. Whilst these suggest reduction in cardiovascular risk with diets high in nitrate-rich vegetables (such as a Mediterranean diet), others have suggested possible small positive and negative associations with dietary nitrate and cancer, but these remain unproven. Interactions with other nutrients, such as vitamin C, polyphenols and fatty acids may enhance or inhibit these effects. In order to provide simple guidance on nitrate intake from different vegetables, we have developed the Nitrate 'Veg- Table' with 'Nitrate Units' [each unit being 1 mmol of nitrate (62 mg)] to achieve a nitrate intake that is likely to be sufficient to derive benefit, but also to minimize the risk of potential side effects from excessive ingestion, given the current available evidence. The lack of data concerning the long term effects of dietary nitrate is a limitation, and this will need to be addressed in future trials.

Fruit and vegetable intake and risk of cardiovascular disease

“…Increasing FV intake will also displace other foods from the diet, and therefore increasing intake may have a broader impact on overall diet if those foods have a macro-and micronutrient profile that is potentially less beneficial to health (69) . Much attention has been paid to specific bioactive compounds found in FV, such as vitamin C (70) , carotenoids (71) , and polyphenols (72) , yet these foods are also rich in fibre (73) and nitrate (74) and, therefore, a diet rich in FV will be rich in a complex mixture of micronutrients, phytochemicals and fibre, with the exact combination dependent on the range of FV consumed. Many components of FV have potential health benefits and while this is scientifically interesting, and ultimately may be important both clinically and to public health, evidence is, as yet, too limited to merit a change public health guidelines to focus on a particular class of FV.…”

Antioxidant properties of polyphenolic rich HPLC standardized extract of Beta vulgaris L. roots

“…Dietary nitrate is essential in reducing blood pressure, inhibition of platelet aggregation and various other vascular effects [8]. Beetroot is known to be therapeutic source of dietary nitrate.…”

Quantitative and Comparative Contents of Nitrate and Nitrite in Beta vulgaris L. by Reversed-Phase High-Performance Liquid Chromatography-Fluorescence

“…The NO 3 − present in this food matrix has been associated with improved cardiovascular function (Hobbs et al 2012;Lidder and Webb 2013). The present study was designed with the purpose of evaluating the NO 3 − and NO 2 − contents in Brazilian and US red beetroots by the RP-HPLC method with fluorescence detection.…”