Robuvit for Stress & Mood: How Horphag's Caffeine-Free Oak Extract Targets Fatigue at the Cellular Level

As consumer demand grows for natural, stimulant-free solutions to everyday stress and fatigue, Robuvit is highlighted as a multifunctional, science-backed supplement in the mood-and-energy category. In this exclusive Q&A, Sébastien Bornet, VP of global sales and marketing at Horphag Research, the worldwide supplier of Robuvit and Pycnogenol, discusses the science behind the French oak wood extract, from its mitochondrial and urolithin-driven mechanisms to key clinical trial data on mood, sleep, and energy.

Robuvit carries more than three decades of clinical validation — 34 clinical trials spanning over 1500 participants — giving formulators and consumers alike evidence to stand on. Bornet highlights a 2018 Journal of Neurosurgical Sciences study showing a 58% reduction in low mood after just eight weeks of supplementation.

The interview also covers formulation versatility across capsules, powders, and beverages, where research gaps remain, and how Robuvit is positioned within the fast-evolving stress-and-mood space.

Erin McEvoy: What consumer need around stress, fatigue, and mood led Horphag Research to develop and study this ingredient?

Sébastien Bornet: While oak has been a venerated tree for centuries, valued for its strength, longevity and traditional use in winemaking, the development of Robuvit began with a much broader scientific exploration. Rather than starting with a specific consumer need or health application, our researchers screened a number of promising botanical candidates to identify extracts with particularly interesting biological activity. French oak wood extract emerged from this process, and early gene-expression studies helped guide our research toward areas related to cellular energy, fatigue, and recovery.

From there, we took the time to build the science before bringing the ingredient to market. More than 7 years passed between the first research on Robuvit and its commercial launch. During that period, Horphag invested extensively in developing the extract, establishing its quality and safety, and building a substantial portfolio of clinical research to understand its potential health applications. Those early findings ultimately led us to investigate Robuvit across interconnected areas including fatigue, energy, recovery, sleep and mood.

McEvoy: How does Robuvit support physical and mental energy at the cellular level, specifically through mitochondrial support and urolithin-driven mitophagy?

Bornet: Robuvit has been clinically studied as a caffeine-free approach to supporting energy and reducing fatigue, while mechanistic research is helping us better understand how these effects may relate to cellular function.

There’s been significant progress in understanding how mitochondria support energy production at the cellular level, a key factor in overall vitality and well-being. One exciting area involves Robuvit’s gut metabolites—Urolithin A and B—which contribute to cellular energy through mitochondria rejuvenation and enhanced protein synthesis. Recent studies show that Robuvit not only reduces fatigue and supports mood stability but also stimulates ribosome biogenesis, boosting the body’s protein production, which is essential for neurotransmitter supporting a healthy stress response.

Because it targets these cellular mechanisms, Robuvit has been clinically shown to reduce fatigue, improve sleep quality, and foster faster recovery. Ultimately, by mitigating oxidative stress and restoring mitochondrial efficiency, Robuvit provides natural physical and mental energy without the crash associated with caffeine making it an ideal, natural solution for managing everyday stress, fatigue, and mood fluctuations.

McEvoy: Which clinical studies best demonstrate Robuvit’s effects on energy, mood, and stress response? What were the populations, doses, durations, primary end points, etc?

Bornet: Various clinical studies have shown that patients experienced higher energy, reduced fatigue and reported improved mood after supplementing with Robuvit.¹ Key research includes:

• A clinical study with 40 subjects, based on the BMIS questionnaire (Brief Mood Introspection Scale) showed a significant impact of Robuvit on mood.² After 8 weeks, the score for the overall mood of the Robuvit group of subjects switched from a majority of unpleasant feelings to a majority of pleasant ones.
• In the same study, individuals suffering from fatigue, unrefreshing sleep, and mood swings showed a clear improvement in the indicated conditions, compared to control participants, after taking Robuvit for 8 weeks. The supplemented subjects had significantly improved mood, felt fitter in the morning with no fatigue during the day and reported an increase in sleep quality by 33%.
• Mood and anxiety disorders are more prevalent in people with chronic fatigue disorder than in people without. A study in individuals with chronic fatigue syndrome demonstrated a 48% improvement in energy and a significant reduction in symptoms like unrefreshing sleep.³
• Another study with subjects with chronic fatigue syndrome for 6 months of daily Robuvit supplementation confirmed these positive effects.⁴ Unrefreshing sleep was significantly reduced by 44%, compared to an increase by 13% in the control group. Problems with short-term memory were reduced by 29% and the mood of the participants taking Robuvit was significantly improved with a 58% reduction of low mood and 49% less mood swings. The control patients showed minimal effects or even slight deterioration.
• Another study investigated subjects suffering from burnout symptoms including significant fatigue. Individuals taking Robuvit for 4 weeks experienced significant relief of emotional drainage and fatigue in comparison with the control group.⁵

McEvoy: What gaps remain in the evidence, and what research is planned next, such as new populations or longer durations?

Bornet: Although Robuvit has already been investigated in 34 clinical trials involving more than 1500 participants, we still see considerable opportunity to deepen our understanding of the extract and its applications. Future research will continue to explore how Robuvit may support energy, fatigue, recovery, sleep and mood across different populations, while also providing further insight into the cellular mechanisms behind these effects.

McEvoy: Robuvit is a 100% water-soluble powder. Which finished formats work best (capsules, powders, gummies, functional beverages), and are there stability or taste considerations?

Bornet: Robuvit is 100% water soluble powder, making it an exceptionally versatile raw material that adapts seamlessly to a wide range of delivery methods including capsules, functional beverages, powders and gummies.

Capsules remain a popular traditional format utilized by many manufacturers. Its water solubility also allows it to be easily formulated into dry powder stick packs available in various flavors. Because of its solubility, it works exceptionally well in beverages and ready-to drink formats, such as a recently launched caffeine-free Robuvit recovery supplement in France, Belgium, and Spain, packaged in ready-to-drink vials in an exotic fruit flavor. Our customers are busy with new formulations, and we are excited and inspired to see the innovation they are lending to the ingredient.

McEvoy: What trends do you see in stress and mood products, and where does Robuvit fit as a natural, caffeine-free option?

Bornet: The stress and mood category is increasingly shifting toward a more integrated approach to wellness, one that recognizes the connection between mental and physical well-being and the relationship between stress, fatigue, energy and mood. Looking ahead, we see a strong demand for natural, clinically studied ingredients that address these interconnected needs simultaneously.

This shift creates ideal landscape for multifunctional ingredients like Robuvit. With clinical research spanning energy, fatigue, sleep, and mood, Robuvit is well positioned for formulations addressing several interconnected aspects of everyday well-being. Robuvit also occupies a distinctive position as a caffeine-free botanical ingredient. Unlike stimulant-based energy products, Robuvit addresses the root biological drivers of fatigue and mood at the cellular level. As a science-backed, natural botanical, it resonates deeply with modern consumers seeking safe, sustainable solutions for daily stress and vitality.

References

1. Science. Robuvit. Accessed October 21, 2026. https://www.robuvit.co.uk/science
2. Belcaro G, Saggino A, Cornelli U, et al. Improvement in mood, oxidative stress, fatigue, and insomnia following supplementary management with Robuvit. J Neurosurg Sci. 2018;62(4):423-427. doi:10.23736/S0390-5616.18.04384-9
3. Belcaro G, Cornelli U, Luzzi R, et al. Robuvit® (quercus robur extract) supplementation in subjects with chronic fatigue syndrome and increased oxidative stress. A pilot registry study. J Neurosurg Sci. 2015;59(2):105-117.
4. Belcaro G, Hosoi M, Feragalli B, Luzzi R, Dugall M. Improved management of primary chronic fatigue syndrome with the supplement French oak wood extract (Robuvit®): a pilot, registry evaluation. Panminerva Med. 2014;56(1):63-72.
5. Belcaro G, Hosoi M, Feragalli B, et al. Supplementation with Robuvit® in subjects with burnout associated to high oxidative stress. Minerva Med. 2018;109(3):211-217.