A naturally occurring polyphenolic stilbene, piceatannol (PIC)’s antioxidant and anti-inflammatory properties have shown promise as a therapeutic agent for obesity, cardiovascular health, and skin aging.
To evaluate the effects of PIC intake on skin hydration and severity of wrinkles, a study funded by Morinaga & Co Ltd was conducted among healthy Japanese women aged 30 to 59 years.
In the randomized, double-blind, placebo-controlled trial, the participants were split into two groups, with the intervention group consuming a drink containing 10mg of PIC derived from passion fruit seeds and the placebo group taking an identical 125ml drink without PIC, once daily for eight weeks.
Stratum corneum hydration and wrinkle grades were assessed at baseline and at the end of the treatment, and results from 82 participants were included in the analysis.
After eight weeks of intake, the PIC group exhibited a statistically significant increase in facial stratum corneum hydration compared to the placebo group, as assessed by two measurement devices.
Specifically, SKICON-200EX employs a high-frequency conductance method that is particularly sensitive to moisture in the more superficial layers of the stratum corneum, while Corneometer CM825 uses a capacitance technique to reflect hydration across the entire thickness of the stratum corneum.
“The fact that both instruments—despite their differing measurement principles—consistently detected increased water content suggested that PIC enhanced hydration throughout the stratum corneum, regardless of the measurement depth,” the authors wrote.
In addition, the PIC group showed a significantly greater reduction in wrinkle grades than the placebo group (p = 0.009), indicating an improvement in crow’s feet.
Wrinkle grades were assessed visually using the grading system defined by the Japanese Cosmetic Science Society (JCSS).
“The findings suggested that PIC, as a dietary ingredient, is effective not only for improving skin moisture retention, but also for improving age-related wrinkle formation.”
Possible mechanisms
Several human studies have demonstrated that PIC ingestion can improve stratum corneum hydration and skin elasticity. However, this is the first clinical trial to simultaneously evaluate its effects on both moisture retention and wrinkle improvement.
In this study, the researchers did not observe a clear correlation between an increase in stratum corneum hydration and improvements in wrinkle grade, suggesting that the anti-wrinkle effects of PIC may involve mechanisms beyond enhanced moisture retention.
“One plausible pathway is the upregulation of Sirtuin 1 (SIRT1), leading to antioxidant and anti-inflammatory actions. Wrinkle formation is known to be driven not only by skin dryness but also inflammation, degeneration of dermal collagen fibers and oxidative stress, and SIRT1 has been implicated in the regulation of these processes.”
Nonetheless, a detailed understanding of the underlying mechanisms would require further multidimensional and application-oriented research to fully characterize the utility of PIC as an ingestible skin health ingredient.
“Future studies should broaden the diversity of study populations, explore different intervention durations and dosages, and investigate the molecular pathways underlying PIC’s actions as well as its effects on additional skin-function endpoints, such as elasticity, colour tone, and barrier recovery.”
Wider implications
According to the authors, the results observed in this study have implications that extend beyond aesthetic benefits and may contribute to the extension of healthy life expectancy in older adults.
The World Health Organization has reframed healthy aging under the concept of “intrinsic capacity”, which is defined as “the composite of all the physical and mental capacities that an individual can draw on at any point in time”.
It comprises five interrelated domains, namely sensory function, locomotor capacity, cognition, psychological well-being, and vitality.
Among these, skin health—particularly parameters such as hydration and wrinkle severity—has been shown to influence psychological aspects, including self-esteem and motivation for social engagement, as well as one’s overall sense of vigor.
“By enhancing the skin’s barrier function and improving visible signs of aging, PIC might support the psychological and vitality domains of intrinsic capacity, eventually helping to maintain or even enhance overall functional capacity in the aging population.”
Source: Frontiers in Nutrition. doi: doi.org/10.3389/fnut.2026.1765478. “Oral supplementation with piceatannol improves skin hydration and reduces wrinkle severity: a randomized, double-blind, placebo-controlled trial”. Authors: Yosuke Seto, et al.
