Eucerin Anti-Pigment Sérum Corporal Para Áreas Sensibles Versus Eucerin Anti-Pigment Dual Serum

Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.

Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.

This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

It works by in inhibiting tyrosinase (the enzyme your melanocytes use to produce melanin) so less pigment ends up deposited in your skin.

Here's something interesting:

Most brightening ingredients you've heard of like kojic acid, arbutin, and even hydroquinone were originally tested on mushroom tyrosinase. And it turns out, mushroom tyrosinase works pretty differently from the human kind.

So Beiersdorf screened 50,000 compounds against actual human tyrosinase, and Thiamidol came out as the strongest. It showed to be more potent than hydroquinone or arbutin at blocking the human enzyme.

It's been shown to fade melasma, post-inflammatory hyperpigmentation, and sun spots at 0.1-0.2% twice daily with visible results in about four weeks. One randomized trial even found 0.2% Thiamidol worked just as well as 4% hydroquinone on melasma but with fewer side effects.

This ingredient is generally well-tolerated and minor irritation has been reported very infrequently.

Be sure to also check out Rucinol, another "hydroquinone alternative".

You might see people debate whether Sodium Chloride is comedogenic, but there actually haven't been any comedogenic tests done on it. Either way, the overall formulation of a product matters a lot more than any single ingredient.

You might see this ingredient used in scrubs as a primary exfoliating ingredient.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

This ingredient is biodegradable and commonly available in natural/COSMOS-certified grades.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

Its main job is chelation; this is a fancy word to say it grabs onto metal ions and neutralizes them. This is because even purified water in cosmetics contains trace amounts of metals that can cause big problems in a formula.

These trace metals can break down actives faster, cause discoloration, promote rancidity in oils, and make preservatives less effective. Trisodium EDTA binds to these metals and takes them out of the equation so your products can stay stable and effective for longer.

There's also an added bonus: by neutralizing the metals ions that bacteria need to thrive, this ingredient also acts as a preservative booster.

The Cosmetic Ingredient Review has concluded this ingredient to be safe as used in cosmetic formulations. It is not considered an irritant, sensitizer, and is barely absorbed through the skin.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!