Dietary nitrate and brain health. Too much ado about nothing or a solution for dementia prevention?

Abstract

Dementia is a significant public health priority with approximately 55 million cases worldwide, and this number is predicted to quadruple by 2050. Adherence to a healthy diet and achieving optimal nutritional status are vital strategies to improve brain health. The importance of this area of research has been consolidated into the new term ‘nutritional psychiatry’. Dietary nitrate, closely associated with the intake of fruits and vegetables, is a compound that is increased in dietary patterns such as the Mediterranean and MIND diets and has protective effects on cognition and brain health. Nitrate is characterised by a complex metabolism and is the precursor of the nitrate–nitrite–nitric oxide (NO) pathway contributing to systemic NO generation. A higher intake of dietary nitrate has been linked to protective effects on vascular outcomes including blood pressure and endothelial function. However, the current evidence supporting the protective effects of dietary nitrate on brain health is less convincing. This article aims to provide a critical appraisal of the current evidence for dietary nitrate supplementation for improving brain health and provide suggestions for future research.

Knowledge and beliefs about dietary inorganic nitrate in a representative sample of adults from the United Kingdom

“…However, with emerging evidence, a new perspective has begun to emerge which suggests that increased intake of nitrate may confer certain health benefits (4,8,9) . Indeed, it has now been demonstrated that consumption of dietary nitrate in the form of vegetables/vegetable-derived products can improve markers of cardiovascular (e.g., reduced blood pressure and improved endothelial function) (10)(11)(12)(13)(14) , brain (e.g., improved cognitive function and modulated cerebral blood flow) (15)(16)(17)(18)(19) , and oral (e.g., modified oral microbiome and increased resilience against oral acidification) health (20)(21)(22) . Similarly, nitrate has been shown to improve exercise capacity/performance across a range of population groups (23)(24)(25) , making it a popular ergogenic aid amongst athletes (3,26) .…”

Exploring the Advantages and Disadvantages of a Whole Foods Approach for Elevating Dietary Nitrate Intake: Have Researchers Concentrated Too Much on Beetroot Juice?

“…For example, dietary nitrate supplementation has been shown to reduce blood pressure (BP) by between ~2 and 10 mmHg [16][17][18][19][20], and could represent a potential adjunct to traditional antihypertensive medications. In addition, dietary nitrate supplementation has been shown to improve endothelial function [17,21], decrease platelet aggregation [17,19], and, albeit less reliably, enhance cerebral blood flow and cognitive function [22][23][24]. Over 100 studies have also been conducted exploring the potential benefits of dietary nitrate for sports performance, with findings from both a recent meta-analysis [25] and Delphi expert consensus [26] suggesting that nitrate can improve performance across a range of exercise modalities and in various populations.…”