 The production in our brain of nitric oxide, the open sesame molecule that dilates our blood vessels and is boosted by the consumption of nitrate-rich vegetables, and the role of nitric oxide in the control of nerve functioning has been comprehensively investigated in lab animals. However, little evidence on its role in human brain function existed until it was put to the test. Feed people lots of green leafy vegetables with some beet juice to boot, and then measure cerebral blood flow. See that spot there with improved flow? That's a critical brain area known to be involved in executive functioning. Not okay, but improved blood flow doesn't necessarily translate into improved cognitive function. For example, feed people tart cherries, and despite some indication of improved blood flow, this didn't appear to manifest as improved cognitive performance. And indeed, some of the initial studies were disappointing. Give people over a cup of cooked spinach and no immediate boost in the ability to carry out simple tasks. But that may be because the tests weren't hard enough. Give people a similar battery of simple tasks after consuming cocoa and no significant effects. But put people through a more demanding set of tasks, and you can see acute improvements in cognitive performance after cocoa consumption. The tasks they're talking about is like counting backwards in threes for minutes at a time. What if you tried doing that same thing after drinking two cups of organic beet juice, which has about the same amount of nitrate as two cups of cooked arugula? Significant improved performance, in terms of more correct answers on the sustained subtraction task. These results suggest that a single dose of nitrate-rich vegetables can modify brain function, and that this is likely to be as a result of increased nitric oxide synthesis. Okay, but how do we know it's the nitrate? Beets are packed with all sorts of phytonutrients like the betal and red pigment. One way to tease it out would be to come up with some kind of nitrate-depleted beet juice, as all the other stuff in beets but just missing the nitrate, to see if that works just as well. And that's exactly what researchers did. They developed a nitrate-depleted beetroot juice placebo. And compared to that, within two weeks of supplementation with the real stuff, this group of diabetics got a significant improvement in reaction time. Now we're just talking 13 milliseconds here, but other interventions like balanced training that only increased reaction time like 7 milliseconds were associated with significantly lower fall risk. And of course in athletes, those fractions of a second can sometimes make a difference. At very high exercise intensities, cognitive task performance deteriorates, with a pronounced detrimental effect on reaction time. And that may be just when you need it the most, like you're playing football or something and need to make rapid, appropriate decisions while simultaneously going all out. And once again, beats to the rescue, significantly reducing reaction time. It's not only improving physical performance, but mental performance as well. Yeah, but can it improve the structure of your brain? Things like cognitive training and aerobic exercise can actually affect the structure of the human brain. There's something called neuroplasticity, where your brain can adapt, changing its configuration as you like learn to play piano or something. We used to think only younger brains could do this, but now we know it can occur in the aging brain as well. Can't beat that, or can you? We didn't know until now. Here's your brain, before and after a six-week exercise program measuring connectivity between various parts of your brain that control movement. No big change, but what about the same amount of exercise before and after drinking some beet juice, too? Big difference. The Exercise Plus Beetroot Juice group developed brain networks that more closely resembled those of younger adults, showing the potential enhanced neuroplasticity conferred by combining exercise and nitrate-rich vegetables.