You have probably heard that the brown bottle alone can transform your skin. Most people use it without knowing what actually makes it famous. This guide covers what its key ingredient, bifida ferment lysate, does for skin, which skin it suits, what to watch, and cheaper alternatives with matching ingredients.
The heart of the serum is bifida ferment lysate, a lysate made by culturing bifidobacteria. It is used to smooth rough texture and hold water in the skin. Here it is one of the largest ingredients after water, so the ingredient the brand talks about really is the backbone of the formula.
Skin feels smoother because hyaluronic acid and glycerin hold water at the surface alongside the ferment, while squalane keeps that water from evaporating. Skin that dries out overnight stays more comfortable until morning, and that is what you can reasonably expect from this serum.
There are supporting players too: bisabolol, known for calming irritated skin, a firming peptide (tripeptide-32), yeast extract and caffeine. Peptides and hyaluronic acid are normally used in small amounts, so what matters is that they are there, not where they sit on the list.
The light, silky feel has a reason as well. The base is water, ferment and solvents that dissolve everything evenly, with no oils or butters, so nothing heavy stays on the skin.
It sinks in without oil, so it works for most skin types. There is no fragrance or alcohol, which leaves little for sensitive skin to react to.
It suits skin that turns rough or dull easily, and anyone who layers several steps and wants one light serum. Despite the "night" in the name, nothing in it needs to stay out of daylight, so morning use is fine.
Nothing in it targets wrinkles or dead skin head on. There is no retinol or exfoliating acid, and no ingredient on Korea's whitening or anti-wrinkle functional lists. "Repair" is the brand's word; by its ingredients this is a hydrating serum that keeps skin in good condition.
It has no fragrance, parabens, mineral oil or alcohol, only a little colorant that tints the liquid. The ingredient side is light; the real question is price.
If the price is too much, start with dupes that share its key ingredients. We compared the full ingredient lists of both products and confirmed the shared actives.
Curious what is in the serum you use now? Check it with the button below.
Analyze this product's ingredients →Cheaper picks confirmed by comparing full ingredient lists with this cream, up to ₩78,470 less.
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This analysis is for general information. Check the product packaging for the actual ingredient list.
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