Dose-response relationship of dietary nitrate-rich beetroot juice on cardiovascular and cognition function in older adults.

In today's society, rates of disease and age-related dysfunction (e.g. cardiovascular disease and dementia) continue to grow rapidly. This has led to an interest in the use of food-based supplements and bio­active compounds to help improve or maintain one’s health and body functions. Beetroot juice has gained recent attention due to its potential health benefits. Beetroot juice contains nitrate, which has been shown to reduce blood pressure and improve physiological responses in younger and older adults, including improved baseline cardiovascular function and exercise performance. Additionally, recent evidence has indicated that increased nitric oxide (the bio­active form of nitrate) may increase blood flow to the brain improving cognition and mood in older adults. Similarly, beetroot juice consumption has been proposed to slow the process of age-related cognitive degradation. However, variations in the dose of dietary nitrate, in the form of beetroot juice, has been shown to result in differing effects on cardiovascular response and cognition in younger and older adults. Some studies have shown that the effects of nitrate supplementation on blood pressure in younger adults occur in a dose-dependent manner, with higher doses having greater effects. This is an import factor to consider when trying to provide the optimal concentration of dietary nitrate to elicit the greatest potential benefits. However, research in this area is limited and no study has investigated the dose-response relationship of dietary nitrate-rich beetroot juice in older adults or on cognitive function. Therefore, the aim of this study is to examine the dose-response effects of four different concentrations of dietary nitrate-rich beetroot juice on cardiovascular function, cognition, and mood in older adults (50 – 80 years).