Simona Mrakic-Sposta, of the Italian National Research Council,  recently published a human study in the peer-reviewed journal Nutrients looking at how beetroot-derived nitrate supplements affect the body in endurance athletes. In this exclusive piece, she explores how the science is still catching up with the category, and how brands can approach formulation of plant-based sports nutrition products in a more evidence-based way.

The sports nutrition industry has an evidence challenge

The sports nutrition sector has evolved significantly over the past decade. Once focused primarily on elite athletes, the category now reaches recreational runners, cyclists, gym-goers and a growing population of consumers seeking products that support active lifestyles and long-term wellbeing.

At the same time, expectations around scientific substantiation have changed. As interest in active nutrition continues to grow, there is increasing focus on understanding not only whether ingredients produce measurable outcomes, but also the physiological pathways through which those outcomes occur.

For plant-based performance ingredients in particular, mechanistic understanding is becoming an increasingly important part of building product credibility.

Why nitric oxide has become a focal point for innovation

Few physiological pathways have attracted as much attention in sports nutrition as nitric oxide metabolism.

Nitric oxide (NO) is a signalling molecule involved in vascular function, blood flow regulation, mitochondrial efficiency and oxygen delivery. Because of its role in exercise physiology, ingredients capable of increasing nitric oxide bioavailability have become a major area of interest for formulators and manufacturers.

This has contributed to growing interest in nitrate-rich ingredients, particularly beetroot-derived formulations used within sports nutrition and active wellness products.

However, discussion of these ingredients frequently centres on performance outcomes such as endurance, exercise efficiency or recovery, while paying less attention to the broader physiological systems involved. From a biological perspective, nitric oxide does not act independently. It interacts with multiple biological mediators involved in vascular and metabolic regulation, and is closely connected with oxidative stress pathways, inflammatory signalling and cellular adaptation mechanisms. Understanding these interactions may help provide a more complete picture of ingredient functionality than outcome measures alone.

The difference between ROS signalling and oxidative damage

One of the most common misconceptions in both sports nutrition and wider wellness discussions is the assumption that increases in reactive oxygen species (ROS) are inherently negative.

In reality, ROS have a dual role. While excessive ROS production can contribute to cellular damage, reactive oxygen species also act as important signalling molecules involved in adaptation and physiological regulation. Exercise itself provides a useful example.

Physical activity naturally induces light oxidative and inflammatory responses within the body. However, these responses are not necessarily indicators of harm. In many cases, they form part of the physiological signalling processes associated with adaptation to exercise.

The challenge for researchers is therefore not simply identifying whether ROS production occurs, but determining whether that activity remains within a physiological range or progresses towards measurable cellular damage. This distinction is particularly important when evaluating performance ingredients designed to influence nitric oxide pathways.

What recent nitrate research is beginning to reveal

Against this backdrop, our recent pilot study published in Nutrients was designed to explore how beetroot-derived nitrate supplementation influences nitric oxide metabolism and oxy-inflammatory biomarkers in amateur endurance athletes.

Using a randomised cross-over design, the study evaluated a beetroot-based nitrate formulation combining nitrate sources with nitric oxide precursors and supportive compounds, over a seven-day supplementation period.

The findings showed a significant increase in nitric oxide metabolites (NOx) in both plasma and urine, with nitric oxide metabolites (NOx) increasing by approximately 155% in plasma and urine.

At the same time, increases were observed in reactive oxygen species (ROS) and interleukin-6 (IL-6), biomarkers commonly associated with oxidative and inflammatory responses. Importantly, however, no significant increase was observed in lipid peroxidation, under the conditions studied.

It is important to note that this was an exploratory pilot study involving a relatively small cohort and did not directly assess performance outcomes. Larger studies will be required to further explore the functional implications of these findings.

These findings, however, highlight an important concept that is often overlooked within discussions around sports nutrition ingredients: biological activation and biological damage are not the same thing.

An increase in oxidative or inflammatory signalling does not automatically indicate a harmful physiological response. In some contexts, these changes may reflect adaptive biological processes rather than pathological stress.

Understanding that distinction is critical if the industry wishes to develop a more sophisticated approach to ingredient evaluation.

What this means for formulators and ingredient suppliers

For manufacturers and ingredient suppliers, these findings highlight the value of incorporating mechanistic evidence alongside outcome-based measures when evaluating plant-based performance ingredients.

As the active nutrition category becomes increasingly competitive, scientific credibility is likely to become a more important differentiator.

Consumers are asking more sophisticated questions about efficacy, bioavailability and long-term physiological impact. At the same time, brands are under increasing pressure to support claims with robust evidence.

This creates an opportunity to move beyond formulation strategies built primarily around outcomes and towards approaches grounded in biological understanding.

For nitrate-based products, that means looking beyond whether an ingredient increases nitric oxide production and considering how it influences broader physiological systems. From a formulation perspective, this points to several important questions: whether an ingredient meaningfully supports relevant physiological pathways, whether this is supported by human biomarker data, and whether claims reflect the strengths and limitations of the available evidence.

Importantly, this approach is not limited to nitrate supplementation. The same principles apply across the wider landscape of plant-based performance ingredients. Whether the ingredient is beetroot-derived nitrate, polyphenol-rich extracts or emerging botanical compounds, the industry increasingly needs evidence that explains not only what an ingredient does, but how and why it does it.

Building the next generation of evidence-backed products

The future of sports nutrition will not be defined solely by new ingredients. It will also be shaped by the quality of the science supporting them.

As the category continues to mature, there is an opportunity for greater emphasis on mechanistic research, human biomarker data and scientifically robust communication.

Plant-based performance ingredients remain one of the most promising areas of innovation within active nutrition. However, unlocking their full potential will require the industry to move beyond performance claims alone and embrace a deeper understanding of human physiology.

Ultimately, the most successful products of the future are likely to be those supported not only by outcomes, but by evidence that explains the biological and molecular pathways responsible for them.