In 1998, three scientists won the Nobel Prize for discovering how a single, invisible gas controls the flow of blood through your body. Decades later, that discovery quietly explains why a glass of beetroot juice can change how far you can ride your bike — and why some of the oldest berries in the Baltic are being re-examined by sports scientists.

Robert Furchgott had a problem. It was the 1970s, and the pharmacologist kept getting contradictory results in his lab in Brooklyn: the same drug would sometimes make a blood vessel contract, and sometimes make it relax. It made no sense — until he realised the answer depended on something almost no one had thought to look at. Whether the delicate inner lining of the vessel, the endothelium, was intact or not.

That single observation cracked open one of the most important discoveries in modern physiology. Furchgott had stumbled onto evidence that the lining of our blood vessels produces a mysterious signalling molecule that tells the vessel walls to relax and widen. He called it, cautiously, "endothelium-derived relaxing factor." For years, nobody knew what it actually was. When the answer finally arrived at a scientific meeting at the Mayo Clinic in the summer of 1986, it was a genuine shock: the mystery molecule was nitric oxide — a colourless, odourless gas, better known at the time as a component of air pollution and cigarette smoke.

The idea that our own cells deliberately manufacture a gas to send signals was so unexpected, and so consequential, that in 1998 Furchgott, Louis Ignarro, and Ferid Murad were awarded the Nobel Prize in Physiology or Medicine for the work. Nitric oxide, it turned out, was one of the master regulators of the cardiovascular system — the body's own way of opening up its blood vessels, lowering pressure, and directing the flow of oxygen-rich blood to where it's needed most.

And here is where the story takes an unexpected turn back toward the dinner table. Because one of the most reliable ways to give your body more of the raw material it needs to make nitric oxide isn't a drug at all. It's a vegetable.

The Beetroot Bombshell

For most of its history, the humble beetroot was known for staining chopping boards and dividing dinner guests. Then sports scientists took an interest, and its reputation changed almost overnight.

The reason lies in a compound beetroot happens to be exceptionally rich in: dietary nitrate. When you consume nitrate — from beetroot, but also from leafy greens like spinach and rocket — your body runs it through a two-step conversion, with the help of bacteria on your tongue, that ends in nitric oxide [1]. In other words, eating nitrate-rich food tops up the very system Furchgott and his colleagues won their Nobel for. More nitric oxide means wider blood vessels, improved blood flow, and more efficient delivery of oxygen to working muscles.

The performance data that followed have been striking. Dietary nitrate has become one of the most rigorously studied ergogenic aids in all of sports science, to the point that an International Olympic Committee consensus statement lists nitrate-rich juices among the supplements with genuine support for exercise performance [2]. The documented effects include extending time to exhaustion in endurance exercise, improving time-trial performance, and enhancing the efficiency of muscle contraction — essentially letting an athlete do more work for the same amount of oxygen [2]. One line of research found that nitrate supplementation improved exercise efficiency by a few percent — a margin that, in endurance sport, is the difference between finishing and winning [3].

Beetroot's benefits aren't confined to elite athletes, either. A meta-analysis of 22 clinical trials concluded that beetroot juice supplementation was associated with meaningful reductions in resting blood pressure [4] — a finding that flows directly from the same vessel-relaxing mechanism. It's a rare example of a food where the folk enthusiasm and the hard clinical data point in the same direction.

It also helps explain why a beetroot-based juice — the deep, earthy blend of beetroot, carrot, and apple you'll find in something like Sage Green's Root Rush — has quietly become a favourite among cyclists and runners who'd rather get their nitrate from a plant than a powder.

The Berries That Speak the Same Language

Beetroot delivers nitrate directly. But there's a second, subtler route to the same destination — and it runs through some of the darkest, most pigment-rich berries in the northern world.

The deep purples, reds, and near-blacks of blackcurrants, aronia, and honeyberries come from a family of plant compounds called anthocyanins. Beyond their colour, anthocyanins have drawn intense scientific interest for their effect on the vascular system: research suggests they can support the body's own production of nitric oxide and encourage the gentle widening of blood vessels [5]. They are, in a sense, speaking the same biochemical language that the Nobel laureates first translated.

The blackcurrant has become an unlikely star of this research. Over the past decade, a substantial body of work — much of it centred on New Zealand blackcurrant — has examined how its anthocyanins affect blood flow and exercise. Studies have reported improved peripheral blood flow, and several trials in trained athletes have found improvements in cycling time-trial and running performance after a week of supplementation [5][6]. It's worth being honest here, in the way good science demands: the results are not unanimous. Some well-designed trials have found no performance benefit, and the effect appears to depend heavily on the type of exercise, the dose, and the individual [6]. What's consistent is the underlying vascular signal; what's still being mapped is exactly when it translates into a faster finish. That kind of nuance is precisely why the blackcurrant remains such an active area of study — and why a pure blackcurrant juice like Sage Green's Midnight Drop represents one of the richest dietary sources of these compounds.

Aronia — the Baltic chokeberry — tells a similar story from a different angle. Among the most polyphenol-dense fruits that grow in the region, aronia has been studied extensively for cardiovascular health. A meta-analysis of controlled clinical trials found that daily aronia supplementation over six to eight weeks was associated with reductions in systolic blood pressure and cholesterol [7], and further trials have pointed to improvements in arterial stiffness and endothelial function — the very lining of the blood vessels where Furchgott's story began [8]. The berry behind juices like Sage Green's Moon Berry and Go-Berry has, in other words, earned a genuine place in the vascular-health conversation. The same holds for the honeyberry — the "berry of long life" of Siberian and Japanese tradition — whose anthocyanin density has made it another northern berry of growing scientific interest, and the heart of Sage Green's Blue North.

The Supporting Cast: Why Vitamin C Belongs in the Story

There's one more character worth introducing, because it works quietly behind the scenes of everything above. Vitamin C is not just an immune-system nutrient; it plays a direct role in energy and endurance in ways that are formally recognised by European food-safety authorities.

Under EFSA-authorised health claims, vitamin C contributes to normal energy-yielding metabolism and to the reduction of tiredness and fatigue — plain, regulated language for a real physiological role [9]. It also contributes to normal collagen formation, which matters more than it sounds: collagen is the structural protein of tendons, ligaments, and blood vessels themselves, the connective tissue that takes a pounding during any kind of physical activity. And vitamin C helps protect cells from the oxidative stress that intense exercise generates.

Few fruits on earth carry more of it than the acerola cherry, a small tropical fruit that is among the densest natural sources of vitamin C known — the foundation of Sage Green's Red Ray. It's the kind of ingredient that doesn't grab headlines the way beetroot does, but underpins the whole system of energy, recovery, and vascular resilience that this article has been circling.

From a Brooklyn Lab to Your Glass

Step back, and the arc is rather beautiful. A confused pharmacologist in the 1970s, a mystery molecule identified in 1986, a Nobel Prize in 1998 — and, decades later, a body of nutritional science showing that some of the oldest, most ordinary plants in the human diet feed directly into that same discovery. Beetroot tops up the nitric oxide system with dietary nitrate. Dark berries support it through their anthocyanins. Vitamin C from fruits like acerola keeps the surrounding machinery of energy and connective tissue running.

None of this is a shortcut, and none of it replaces training, rest, or a balanced diet — the science is clear-eyed about that, and so are we. What it offers instead is something quieter and more interesting: a reminder that the "natural energy" so many of us are chasing isn't really about caffeine or sugar at all. It's about blood flow — the unglamorous, invisible business of getting oxygen-rich blood to where your body needs it. That's the system three scientists decoded a quarter-century ago. And it turns out the plant world has been speaking its language all along.

This article is for general educational purposes and is not medical advice. If you have a cardiovascular condition, take medication that affects blood pressure, or are planning significant changes to your diet or training, please consult a qualified healthcare professional.

References

1. Lundberg, J. O., Weitzberg, E., & Gladwin, M. T. (2008). The nitrate-nitrite-nitric oxide pathway in physiology and therapeutics. Nature Reviews Drug Discovery, 7(2), 156-167.
2. Maughan, R. J., et al. (2018). IOC consensus statement: dietary supplements and the high-performance athlete. British Journal of Sports Medicine, 52(7), 439-455. (Dietary nitrate / beetroot juice among supported ergogenic aids.)
3. Bailey, S. J., et al. / Gatorade Sports Science Institute review. Dietary nitrate and exercise performance: enhanced muscle contraction efficiency. gssiweb.org.
4. Bahadoran, Z., Mirmiran, P., Kabir, A., Azizi, F., & Ghasemi, A. (2017). The nitrate-independent blood pressure-lowering effect of beetroot juice: a systematic review and meta-analysis. Advances in Nutrition, 8(6), 830-838.
5. Cook, M. D., & Willems, M. E. T. (2019). Dietary anthocyanins and blackcurrant: effects on blood flow and exercise performance. Reviewed in Frontiers in Nutrition, 7, 74 (Barnes et al., 2020).
6. Braakhuis, A. J., & Hopkins, W. G., et al. — reviews of New Zealand blackcurrant supplementation and cycling/running performance (mixed, exercise-mode-dependent results). Sports (MDPI), 11(5), 93, 2023; European Journal of Sport Science, 2025.
7. Hawkins, J., et al. (2021). Daily supplementation with Aronia melanocarpa (chokeberry) reduces blood pressure and cholesterol: a meta-analysis of controlled clinical trials. Journal of Dietary Supplements.
8. Istas, G., et al. (2019). Effects of aronia berry (poly)phenols on vascular function and gut microbiota: a double-blind randomized controlled trial. American Journal of Clinical Nutrition, 110(2), 316-329.
9. European Food Safety Authority (EFSA). Scientific opinions on vitamin C: contribution to normal energy-yielding metabolism, reduction of tiredness and fatigue, normal collagen formation, and protection of cells from oxidative stress. EFSA Journal, authorised Article 13 health claims.