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Hada Labo Shiro-Jyun Serum

Shiro-Jyun Serum

Hada Labo Shirojyun Serum 1.1 oz (30 g) by molonaConcentrated formula, brightens and hydratesHelp reduce the visible signs of age spots and sun damage. Free- fromMineral OilDyesFragranceNon comedogenicPH balancedTarget key [more] [more] areas or your entire face and neck by applying morning or night with the Hada Labo patting technique. Then lock in with Hada Labo Shiro-jyun Milk or Hada Labo Shiro-jyun Cream for brighter, smoother skin [less]
Uploaded by: charikleia on 20/06/2019

Hada Labo Shiro-Jyun Serum
Ingredients explained

Also-called: Aqua | What-it-does: solvent

Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product. 

It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water. 

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Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying. 

One more thing: the water used in cosmetics is purified and deionized (it means that almost all of the mineral ions inside it is removed). Like this, the products can stay more stable over time. 

What-it-does: moisturizer/humectant, solvent | Irritancy: 0 | Comedogenicity: 1

Butylene glycol, or let’s just call it BG, is a multi-tasking colorless, syrupy liquid. It’s a great pick for creating a nice feeling product.  

BG’s main job is usually to be a solvent for the other ingredients. Other tasks include helping the product to absorb faster and deeper into the skin (penetration enhancer), making the product spread nicely over the skin (slip agent), and attracting water (humectant) into the skin.

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It’s an ingredient whose safety hasn’t been questioned so far by anyone (at least not that we know about). BG is approved by Ecocert and is also used enthusiastically in natural products. BTW, it’s also a food additive. 

Diglycerin - goodie

The big brother of glycerin. It's also a natural moisturizing factor that reduces water evaporation from the upper layer of the skin and helps to keep water in the skin so that it stays nicely hydrated.

Compared to glycerin, it has a larger molecular structure (kind of a double glycerin). Thanks to this, it penetrates slower into the skin but gives longer lasting moisture and less sticky, better skin-feel.

Arbutin - goodie
Also-called: Beta-Arbutin | What-it-does: antioxidant, skin brightening

A pretty well-known and often used ingredient with the magic ability to fade brown spots. It's used traditionally in Japan and can be found naturally in a couple of plants, including the leaves of pear trees, wheat and bearberry

Arbutin seems to work its magic and hinder the pigmentation process at the second step of it. An enzyme called tyrosinase is needed to create melanin (the pigment that causes the brown spots) and while several other skin lightening agents work to inhibit the synthesis of tyrosinase itself (like vitamin C or licorice), arbutin lets tyrosinase be and rather hinders the melanin-forming activity of the enzyme. (So it might be a good idea to combine arbutin with some direct tyrosinase inhibitors for more skin lightening effect.)

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All in all, arbutin is one of the better-known skin brightening agents, that's probably worth a try if pigmentation is an issue for you.

Also-called: Meadowfoam Oil | What-it-does: emollient

The emollient plant oil coming from the seeds of the white flowering plant called meadowfoam.  Meadowfoam Oil has a unique fatty acid composition with 95% of it being long chain fatty acids (eicosenoic acid C20:1 - 61%, docosenoic acid C22:1 - 16% and docosadienoic acid C22:2 - 18%) that make the oil extraordinarily stable. It also contains antioxidant components such as vitamin E as well as phytosterols.

Apart from Meadowfoam Oil's crazy stability, the oil is described as non-greasy, rapidly absorbed and having a similar skin feel to more often used jojoba oil. The oil is ideal for products where a soft, smooth, silky feel is required whether it be on skin or hair.

Though its long name does not reveal it, this polymer molecule (big molecule from repeated subunits or monomers) is a relative to the super common, water-loving thickener, Carbomer. Both of them are big molecules that contain acrylic acid units, but Acrylates/C10-30 Alkyl Acrylate Crosspolymer also contains some other monomers that are hydrophobic, i.e. water-hating. 

This means that our molecule is part water- and part oil-loving, so it not only works as a thickener but also as an emulsion stabilizer. It is very common in gel-type formulas that also contain an oil-phase as well as in cleansers as it also works with most cleansing agents (unlike a lot of other thickeners). 

What-it-does: emollient | Irritancy: 0 | Comedogenicity: 1

Probably the most common silicone of all. It is a polymer (created from repeating subunits) molecule and has different molecular weight and thus different viscosity versions from water-light to thick liquid.

As for skincare, it makes the skin silky smooth, creates a subtle gloss and forms a protective barrier (aka occlusive). Also, works well to fill in fine lines and wrinkles and give skin a plump look (of course that is only temporary, but still, it's nice). There are also scar treatment gels out there using dimethicone as their base ingredient. It helps to soften scars and increase their elasticity. 

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As for hair care, it is a non-volatile silicone meaning that it stays on the hair rather than evaporates from it and smoothes the hair like no other thing. Depending on your hair type, it can be a bit difficult to wash out and might cause some build-up (btw, this is not true to all silicones, only the non-volatile types). 

What-it-does: viscosity controlling

A white, elastomeric silicone powder that gives a nice silky and powdery feel to the products. It also has some oil and sebum absorption capabilities. 

What-it-does: chelating

Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes.

What-it-does: emollient, emulsifying | Irritancy: 0 | Comedogenicity: 1-2

A super common, waxy, white, solid stuff that helps water and oil to mix together, gives body to creams and leaves the skin feeling soft and smooth.

Chemically speaking, it is the attachment of a glycerin molecule to the fatty acid called stearic acid. It can be produced from most vegetable oils (in oils three fatty acid molecules are attached to glycerin instead of just one like here) in a pretty simple, "green" process that is similar to soap making. It's readily biodegradable.

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It also occurs naturally in our body and is used as a food additive. As cosmetic chemist Colins writes it, "its safety really is beyond any doubt".

Also-called: HEC | What-it-does: viscosity controlling

A nice little helper ingredient that can thicken up cosmetic products and create beautiful gel formulas. It's derived from cellulose, the major component of the cell wall of green plants. It is compatible with most co-ingredients and gives a very good slip to the formulas. 

Also-called: Form of Vitamin C, MAP | What-it-does: skin brightening

A form of skincare superstar, Vitamin C. If you do not know, what the big deal about Vitamin C is, click here and read all about it, we will wait here for you. 

So now you know that pure vitamin C (aka ascorbic acid, AA) is really unstable and hard to formulate so the cosmetics industry is coming up with a bunch of derivatives to solve the problem and Magnesium Ascorbyl Phosphate (or MAP) is one of them.  

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MAP does solve the stability problem: it's stable up to pH 7, so far so good. What is not so good is that, as the great review study about vitamin C derivatives in the Journal of Cosmetic Dermatology writes, MAP is "at very best, poorly absorbed in comparison to AA." 

Moreover,  derivatives not only have to be absorbed into the skin, they also have to be converted into pure AA. The good news is that in-vitro data shows that MAP does convert, but the bad news is we do not really know if the same is true on real, living human skin. Even if it does, we don't know how good the conversion rate is (but to be fair the same is true for all other derivatives).

Regarding the three magic abilities of pure vitamin C (antioxidant, collagen booster, skin brightener), there is no published data about MAP's antioxidant or photoprotection capabilities. We have better news about the other two things: in-vitro data shows that MAP can boost collagen synthesis similar to AA (though in the case of AA it's proven in-vivo) and even better, MAP is proven to work as a skin brightener in-vivo (on real people). 

Bottom line: when it comes to vitamin C derivatives, MAP is definitely an option. We especially recommend it if you are after skin brightening as this seems to be the strongest point of MAP. 

 

What-it-does: preservative | Irritancy: 0 | Comedogenicity: 0

The most common type of feared-by-everyone-mostly-without-scientific-reason parabens. It's a cheap, effective and well-tolerated ingredient to make sure the cosmetic formula does not go wrong too soon

Apart from the general controversy around parabens (we wrote about it more here), there is a 2006 in-vitro (made in the lab not on real people) research about methylparaben (MP) showing that when exposed to sunlight, MP treated skin cells suffered more harm than non-MP treated skin cells. The study was not done with real people on real skin but still - using a good sunscreen next to MP containing products is a good idea. (Well, in fact using a sunscreen is always a good idea. :))

We don't have description for this ingredient yet.

What-it-does: preservative | Irritancy: 0 | Comedogenicity: 0

A very common type of feared-by-everyone-mostly-without-scientific-reason parabens. It's a cheap, effective and well-tolerated ingredient to make sure the cosmetic formula does not go wrong too soon.

What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

It’s the - sodium form - cousin of the famous NMFhyaluronic acid (HA). If HA does not tell you anything we have a super detailed, geeky explanation about it here.  The TL; DR version of HA is that it's a huge polymer (big molecule from repeated subunits) found in the skin that acts as a sponge helping the skin to hold onto water, being plump and elastic. HA is famous for its crazy water holding capacity as it can bind up to 1000 times its own weight in water.

As far as skincare goes, sodium hyaluronate and hyaluronic acid are pretty much the same and the two names are used interchangeably. As cosmetic chemist kindofstephen writes on reddit  "sodium hyaluronate disassociates into hyaluronic acid molecule and a sodium atom in solution". 

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In spite of this, if you search for "hyaluronic acid vs sodium hyaluronate" you will find on multiple places that sodium hyaluronate is smaller and can penetrate the skin better. Chemically, this is definitely not true, as the two forms are almost the same, both are polymers and the subunits can be repeated in both forms as much as you like. (We also checked Prospector for sodium hyaluronate versions actually used in cosmetic products and found that the most common molecular weight was 1.5-1.8 million Da that absolutely counts as high molecular weight).

What seems to be a true difference, though, is that the salt form is more stable, easier to formulate and cheaper so it pops up more often on the ingredient lists. 

If you wanna become a real HA-and-the-skin expert you can read way more about the topic at hyaluronic acid (including penetration-questions, differences between high and low molecular weight versions and a bunch of references to scientific literature).

What-it-does: buffering | Irritancy: 0 | Comedogenicity: 2

It’s a little helper ingredient that helps to set the pH of a cosmetic formulation to be just right. It’s very alkaline (you know the opposite of being very acidic): a 1% solution has a pH of around 10.

It does not have the very best safety reputation but in general, you do not have to worry about it. 

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What is true is that if a product contains so-called N-nitrogenating agents (e.g.: preservatives like 2-Bromo-2-Nitropropane-1,3-Diol, 5-Bromo-5-Nitro- 1,3-Dioxane or sodium nitrate - so look out for things with nitro, nitra in the name) that together with TEA can form some not nice carcinogenic stuff (that is called nitrosamines). But with proper formulation that does not happen, TEA in itself is not a bad guy. 

But let’s assume a bad combination of ingredients were used and the nitrosamines formed. :( Even in that case you are probably fine because as far as we know it cannot penetrate the skin. 

But to be on the safe side, if you see Triethanolamine in an INCI and also something with nitra, nitro in the name of it just skip the product, that cannot hurt.

You may also want to take a look at...

what‑it‑does solvent
Normal (well kind of - it's purified and deionized) water. Usually the main solvent in cosmetic products. [more]
what‑it‑does moisturizer/humectant | solvent
irritancy, com. 0, 1
An often used glycol that works as a solvent, humectant, penetration enhancer and also gives a good slip to the products. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
The big brother of glycerin. A natural moisturizing factor that compared to glycerin penetrates slower into the skin but gives longer lasting moisture and less sticky, better skin-feel. [more]
what‑it‑does antioxidant | skin brightening
One of the better-known skin brightening agents that's found naturally for example in bearberry. [more]
what‑it‑does emollient
Meadowfoam Oil - An emollient plant that is stable, non-greasy and rapidly absorbed. It gives a soft, smooth, silky skin feel. [more]
what‑it‑does viscosity controlling
A common helper ingredient that stabilizes emulsions and helps to thicken up products. [more]
what‑it‑does emollient
irritancy, com. 0, 1
A very common silicone that gives both skin and hair a silky smooth feel. It also forms a protective barrier on the skin and fills in fine lines. Also used for scar treatment. [more]
what‑it‑does viscosity controlling
A white, elastomeric silicone powder that gives a nice silky and powdery feel to the products. [more]
what‑it‑does chelating
Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes. [more]
what‑it‑does emollient | emulsifying
irritancy, com. 0, 1-2
Waxy, white, solid stuff that helps water and oil to mix together and leaves the skin feeling soft and smooth. [more]
what‑it‑does viscosity controlling
A nice little helper ingredient that can thicken up cosmetic products and create beautiful gel formulas. It's derived from cellulose, the major component of the cell wall of green plants. [more]
what‑it‑does skin brightening
A form of skincare superstar, Vitamin C - it has proven skin-brightening abilities (in-vivo) and it might be able to boost collagen production as well (in-vitro). [more]
what‑it‑does preservative
irritancy, com. 0, 0
The most common type of feared-by-everyone-mostly-without-scientific-reason parabens. It's a cheap, effective and well-tolerated ingredient to make sure the cosmetic formula does not go wrong too soon.  Apart from the general controversy around parabens (we wrote about it more here), there is a 2006 in-vitro (made in the lab not on real people) research about methylparaben (MP) sho [more]
what‑it‑does emulsifying | surfactant/cleansing
what‑it‑does preservative
irritancy, com. 0, 0
A very common type of feared-by-everyone-mostly-without-scientific-reason parabens. It's a cheap, effective and well-tolerated ingredient to make sure the cosmetic formula does not go wrong too soon. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
It's the salt form of famous humectant and natural moisturizing factor, hyaluronic acid. It can bind huge amounts of water and it's pretty much the current IT-moisturizer. [more]
what‑it‑does buffering
irritancy, com. 0, 2
Helps to set the pH of a cosmetic formulation to be right. It’s very alkaline. [more]