Nitric Oxide: What It Is & Why It Matters
What is Nitric Oxide?
Nitric oxide (NO) is a naturally occurring molecule produced in your body.
It acts as a signaling molecule, meaning it helps cells communicate and regulate important functions.
In the body, NO is mainly produced in the inner lining of blood vessels (the endothelium).
Key Roles of Nitric Oxide in the Body
Vasodilation: NO relaxes and widens blood vessels, improving blood flow and lowering blood pressure.
Oxygen Delivery: By increasing blood flow, NO helps deliver more oxygen and nutrients to muscles and organs—especially important during exercise.
Exercise Performance: Higher NO levels can improve endurance, reduce the oxygen cost of exercise, and support better recovery.
Heart Health: Supports healthy blood pressure and overall cardiovascular function.
Brain Function: Plays a role in memory, learning, and protecting brain cells.
Nitrate-Rich Foods: Impact on Exercise, Brain Health, and Cognitive Performance
Research highlights the powerful effects of dietary nitrate—primarily found in beetroot juice and leafy greens—on both physical and cognitive health. When consumed, these nitrates are converted in the body to nitric oxide, a molecule that relaxes blood vessels, enhances blood flow, and supports oxygen delivery to muscles and the brain.
Exercise Efficiency and Endurance Multiple studies show that supplementing with dietary nitrate can make exercise feel easier and more productive. Healthy adults who drank beetroot juice for several days experienced a significant increase in blood nitrite levels, which is associated with improved nitric oxide production. This led to:
Lower systolic blood pressure,
Reduced oxygen cost during moderate-intensity exercise (meaning muscles needed less oxygen for the same amount of work),
More efficient muscle oxygen use,
Reduced markers of fatigue during high-intensity activity,
And, notably, a longer time to exhaustion during strenuous exercise.
These findings suggest that nitrate-rich foods can help individuals exercise more efficiently and potentially improve endurance, likely by optimizing how muscles use oxygen and by supporting healthy mitochondrial function.
Brain Blood Flow and Cognitive Performance The benefits of dietary nitrate extend beyond physical performance. Studies involving both older adults and healthy adults of various ages have demonstrated that a high-nitrate diet can influence blood flow to the brain and support cognitive function. In older adults, consuming more dietary nitrate increased blood flow to critical regions of the frontal lobe—areas involved in executive function and decision-making—even though overall brain blood flow remained unchanged. In healthy adults, a single dose of beetroot juice increased blood flow in the prefrontal cortex during cognitive tasks and led to more efficient oxygen use in the brain during less demanding tasks.
Importantly, these changes in blood flow were accompanied by improvements in cognitive performance, especially on tasks requiring executive function and mental processing speed. Blood tests confirmed that dietary nitrate was effectively converted to nitrite and then to nitric oxide in the body, supporting the physiological link between nitrate-rich foods and these health benefits.
What This Means for You Including nitrate-rich vegetables—like beets, beetroot juice, spinach, arugula, and Swiss chard—in your regular diet may help:
Lower blood pressure,
Make exercise more efficient and less tiring,
Enhance endurance and performance,
Improve blood flow to key brain regions,
And support better cognitive performance, particularly for tasks that require focus, quick thinking, and decision-making.
Bottom Line: Nitrate-rich foods offer a natural, evidence-based way to support both your physical and mental performance. For busy adults striving to maximize their health, stamina, and brainpower, regularly including these vegetables as part of a balanced diet is a practical and effective strategy.
References:
Bailey SJ, et al. (2009). "Dietary nitrate supplementation reduces the O2 cost of low-intensity exercise and enhances tolerance to high-intensity exercise in humans."
Presley TD, et al. (2011). "Acute effect of a high nitrate diet on brain perfusion in older adults." Nitric Oxide, 24(1), 34–42.
Wightman EL, et al. (2015). "Dietary nitrate modulates cerebral blood flow parameters and cognitive performance in humans: A double-blind, placebo-controlled, crossover investigation." Physiology & Behavior, 149, 149–158.
