The science
Why it works
This page explains what is in the serum and why we chose it. The short version: one plant-derived active, a few supporting botanicals, and no synthetic fragrance.
Plant placenta
Plant placenta, from rose cell culture
In a plant, the placenta is the tissue that feeds the seed. It is the most active, nutrient-rich part of the flower, at the point where it is building new life. Ours comes from the damask rose (Rosa damascena), grown in cell culture rather than cut from a field. Nothing in it comes from an animal.
The extract is taken at the stage in the rose's life cycle when cell activity is highest, which is where its capacity for growth and repair is concentrated.
What it does for skin
- Supports skin renewal and repair by encouraging healthy cell turnover
- Strengthens the skin barrier and helps it hold moisture
- Supports firmness and elasticity (collagen support)
- Helps brighten and smooth skin texture
- Antioxidant protection against everyday stress
- Calms and balances stressed or sensitive skin
How it works, in one line: studies on rose placenta point to support for epidermal growth factor (EGF) activity and the NRF2 antioxidant pathway. In simpler terms, the signals skin uses to repair itself and defend against oxidative stress.
Why rose
Why the rose
We could have built the formula around any plant. We chose the rose because of what it does for the kind of skin we had in mind. It balances: it helps steady oil without stripping, it calms skin that reacts easily, and it suits warm, humid weather, which is where most of our customers live.
Supporting botanicals
What else is in it
A short list of plant extracts that support the main active. Each one is there for a reason.
Centella asiatica (cica)
Helps skin recover and stay resilient.
Aloe vera
Soothes dryness and keeps skin comfortable.
Peony root
Helps skin look more even and bright.
Strawberry begonia
For a smoother, more toned look.
Kudzu root
Brings back suppleness and bounce.
Chlorella
Supports collagen and renewal.
Rose geranium oil
Helps regulate sebum, and gives the serum its light natural scent.
Phytic acid
A gentle plant-derived antioxidant that keeps the formula stable.
Hwasoo-23™
The formula has a name
We call the complete complex Hwasoo-23. Hwasoo (花素) roughly translates as floral essence, and 23 is for the chromosome pairs and the year we began. It is just the name of the formula. What matters is what it does for your skin.
1
Renewal, gently
Rose phytoplacenta encourages renewal without disrupting the skin.
2
Barrier first
Formulated to strengthen resilience and suit sensitive skin.
3
Botanicals in balance
Firming, brightening and calming extracts working together.
Physician-formulated
Clinical intention meets botanical intelligence
H23 is formulated in Japan under the guidance of a practicing physician, informed by a clinical understanding of skin as a living, adaptive system.
Developed to Japanese manufacturing standards with rigorous quality control and ongoing research and development, each formula is grounded in clinical science and carefully curated for safe, consistent, everyday skincare.
- Designed for daily use, including sensitive and environmentally stressed skin
- Prioritises cumulative skin health over short-term sensation or trends
- Selected for proven efficacy, supported by scientific research
- Rooted in balance, prevention, and supporting the skin's natural rhythm
- No synthetic fragrance. Free from phthalates, parabens, SLS and SLES, oxybenzone and gluten. No animal testing.
Tester panel
What our testers noticed
47 women, 8 weeks, daily use, self-reported. This was a tester panel, not a clinical study, and we would rather say so plainly. Here is what 47 women told us after eight weeks of using the serum every day.
Hydration
86%noticed improved hydration
Sensitivity and barrier
83%felt calmer, more comfortable skin
Texture
81%noticed softer, smoother texture
Pigmentation
78%noticed brighter, more even tone
Fine lines
74%noticed smoother-looking lines
Firmness
72%noticed improved bounce
Pores
70%noticed clearer-looking pores
Breakouts
69%reported fewer visible breakouts
Oiliness
66%felt more balanced skin
Under-eyes
61%noticed fresher-looking under-eyes
Survey results are based on a limited sample size and self-reported feedback. Individual results may vary depending on skin type, routine, and consistency of use. This product is not intended to diagnose, treat, cure, or prevent any medical condition.
Full ingredient list
Everything in the bottle
Water, Butylene Glycol, Rosa Damascena Phytoplacenta Culture Extract, Pentylene Glycol, Saxifraga Sarmentosa Extract, Paeonia Suffruticosa Root Extract, Aloe Barbadensis Leaf Extract, Chlorella Vulgaris Extract, Pueraria Lobata Root Extract, Centella Asiatica Leaf/Stem Extract, 1,2-Hexanediol, PEG-60 Hydrogenated Castor Oil, Algin, Carbomer, Potassium Hydroxide, Phytic Acid, Phenoxyethanol, Pelargonium Graveolens Oil
Free from parabens, phthalates, SLS and SLES, oxybenzone and gluten. Not tested on animals. Made in Japan.
No synthetic fragrance. The light scent comes from natural rose geranium oil.
