A recent Italian study published in the journal Nutrients reports on Apr. 13 that a beetroot-based nitrate supplement led to significant changes in nitric oxide and redox pathways among amateur triathletes after just one week of use. The research did not determine whether these biochemical shifts resulted in improved endurance or recovery.
The findings are important because nitric oxide plays a key role in regulating blood flow, metabolism, and muscle function—factors relevant to athletic performance. However, while dietary sources like beetroot have been shown to increase nitric oxide availability, there is still limited evidence on how this translates into real-world benefits for athletes.
In the randomized crossover pilot trial, ten healthy male amateur triathletes aged 30–59 years participated. Each followed two seven-day phases—one with the supplement and one as a control—with a break between them. The dose was adjusted based on body weight and included other ingredients such as L-citrulline, L-arginine, carbohydrates, and N-acetylcysteine alongside beetroot-derived nitrate. Researchers collected blood and urine samples at several points to measure biomarkers linked to nitric oxide production, oxidative stress, and inflammation.
After one week of supplementation, participants showed marked increases in key biomarkers: NO metabolites rose by 155%, peroxynitrite by 60%, inducible nitric oxide synthase by 56%, interleukin-6 cytokine by 73%, reactive oxygen species by over four times baseline levels (413%), and smaller increases were seen for other markers. Despite these elevations indicating increased redox activity and immune response activation—which researchers say may reflect adaptive physiological processes—there was no evidence of lipid oxidative damage or adverse effects apart from mild loose stools reported by one participant.
The authors interpret the rise in reactive oxygen species and cytokines as part of controlled adaptations rather than harmful inflammation or oxidative stress. The study’s design included standardized lab methods for measuring outcomes but did not assess direct impacts on exercise performance or recovery times.
Researchers caution that more extensive placebo-controlled studies are needed before drawing conclusions about practical benefits for athletes. They suggest future work should include larger sample sizes with diverse populations as well as functional measures like endurance testing to clarify if such supplements can enhance training outcomes.
