Hylamide Booster C25
A serum with 4 ingredients, including vitamin C.
This brightening serum is formulated around 3-O-Ethyl Ascorbic Acid and Phenylethyl Resorcinol to brighten dull-looking skin and fade the look of dark spots.
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What's inside
Key Ingredients
Benefits
Ingredients Explained
Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.
It’s often used to:
Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.
Learn more about Propanediol3-O-Ethyl Ascorbic Acid is one of the most popular "stable" vitamin C derivatives in skincare.
Plain ascorbic acid is fantastic but notoriously fragile; it browns, oxidizes, and loses potency fast. So attaching an ethyl group to the third carbon of the molecule gives it some cool perks:
In a formula, it does the 3 classic vitamin C jobs: it acts as an antioxidant, helps brighten skin tone by inhibiting tyrosinase, and supports collagen.
The evidence is reasonably solid for a cosmetic ingredient; Liao and colleagues (2018) showed it's significantly more stable than ascorbic acid while still being effective.
A 2021 study by Zerbinati and colleagues tested a serum with 30% 3-O-ethyl-l-ascorbic acid and 1% lactic acid significantly increased collagen production, reduced UVB-induced DNA damage, and decreased melanin on a reconstructed pigmented skin model.
Typical real world usage sits around 0.5-5% (and 1-2% is common for daily serums).
Amounts up to 30% have been shown to be non-irritating on human skin samples, but two isolated cases reported allergic contact dermatitis so a patch test is sensible if you have reactive skin.
Learn more about 3-O-Ethyl Ascorbic AcidWe don't have a description for Hydroxyphenoxy Propionic Acid yet.
Phenylethyl Resorcinol (PR) is a synthetic antioxidant and tyrosinase inhibitor. This ingredient is found naturally in pine trees.
What is a tyrosinase inhibitor?
Tyrosinase is an enzyme that plays a key role in melanin production, which leads to skin darkening when exposed to UV light. By inhibiting this enzyme, PR can help with skin brightening and lifting dark spots.
The manufacturer states 0.5% of PR is more effective than 1% kojic acid. In 2013, a study of 80 participants found combining PR with other skin-brightening ingredients found 57% showed moderate improvement and 17% saw no change. Another study with 20 women reported a 43% reduction in uneven skin tone.
While more research is needed to fully confirm PR's efficacy, there’s no harm in trying it - especially when combined with other proven skin-brightening ingredients.
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Where it's from
Hylamide is a Canadian brand
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The data we've presented on this page has been verified by a member of the SkinSort Team.
Read more about us· Updated October 28, 2025 • Added by honeybee25
