Highlights
Skim through
| Ingredient name | what-it-does | irr., com. | ID-Rating |
|---|---|---|---|
| Water | solvent | ||
| Glycerine | skin-identical ingredient, moisturizer/humectant | 0, 0 | superstar |
| Mineral Oil | emollient, solvent | 0, 0-2 | |
| Squalane | skin-identical ingredient, emollient | 0, 1 | goodie |
| Butylene Glycol | moisturizer/humectant, solvent | 0, 1 | |
| Petrolatum | emollient | ||
| Butyrospermum Parkii Butter | emollient | goodie | |
| Honey | soothing, moisturizer/humectant, antimicrobial/antibacterial | goodie | |
| Prunus Persica Leaf Extract | emollient, moisturizer/humectant | ||
| Betaine | moisturizer/humectant | goodie | |
| Sodium Hyaluronate | skin-identical ingredient, moisturizer/humectant | 0, 0 | goodie |
| Steareth-6 | emulsifying, surfactant/cleansing | ||
| Sodium Hydroxide | buffering | ||
| Carbomer | viscosity controlling | 0, 1 | |
| Tetrasodium EDTA | chelating | ||
| Methylparaben | preservative | 0, 0 | |
| Ethylparaben | preservative |
Matsukiyo Body Milk (fragrance-free)Ingredients explained
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.
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.
- A natural moisturizer that’s also in our skin
- A super common, safe, effective and cheap molecule used for more than 50 years
- Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
- Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
- High-glycerin moisturizers are awesome for treating severely dry skin
The famous or maybe rather infamous mineral oil. The clear oily liquid that is the "cheap by-product" of refining crude oil and the one that gets a lot of heat for its poor provenance. It is a very controversial ingredient with pros and cons and plenty of myths around it. So let us see them:
The pros of mineral oil
Trust us, if something is used for more than 100 years in cosmetic products, it has advantages. Chemically speaking, cosmetic grade mineral oil is a complex mixture of highly refined saturated hydrocarbons with C15-50 chain length. It is not merely a "by-product" but rather a specifically isolated part of petroleum that is very pure and inert.
It is a great emollient and moisturizer working mainly by occlusivity. Occlusivity is one of the basic mechanisms of how moisturizers work and it means that mineral oil sits on top of the skin and hinders so-called trans-epidermal water loss, i.e water evaporating out of your skin. When compared to heavy-duty plant oil, extra virgin coconut oil, the two of them were equally efficient and safe as moisturizers in treating xerosis, a skin condition connected to very dry skin.
The other thing that mineral oil is really good at is being non-irritating to the skin. The chemical composition of plant oils is more complex with many more possible allergens or irritating components, while mineral oil is simple, pure and sensitivity to it is extremely rare. If you check out the classic French pharmacy brands and their moisturizers for the most sensitive, allergy prone skin, they usually contain mineral oil. This is no coincidence.
The cons of mineral oil
The pros of mineral oil can be interpreted as cons if we look at them from another perspective. Not penetrating the skin but mostly just sitting on top of it and not containing biologically active components, like nice fatty acids and vitamins mean that mineral oil does not "nourish" the skin in the way plant oils do. Mineral oil does not give the skin any extra goodness, it is simply a non-irritating moisturizer working mainly by occlusivity.
The myths around mineral oil
Badmouthing mineral oil is a favorite sport of many, it is a cheap material and being connected to petrolatum makes it fairly easy to demonize.
While it is true that industrial grade mineral oil contains carcinogenic components (so-called polycyclic compounds), these are completely removed from cosmetic and food grade mineral oil and there is no scientific data showing that the pure, cosmetic grade version is carcinogenic.
What is more, in terms of the general health effects of mineral oils used in cosmetics, a 2017 study reviewed the data on their skin penetration and concluded that "the cosmetic use of mineral oils and waxes does not present a risk to consumers due to a lack of systemic exposure."
Another super common myth surrounding mineral oil is that it is comedogenic. A 2005 study titled "Is mineral oil comedogenic?" examined this very question and guess what happened? The study concluded that "based on the animal and human data reported, along with the AAD recommendation, it would appear reasonable to conclude that mineral oil is noncomedogenic in humans."
Overall, we feel that the scaremongering around mineral oil is not justified. For dry and super-sensitive skin types it is a great option. However, if you do not like its origin or its heavy feeling or anything else about it, avoiding it has never been easier. Mineral oil has such a bad reputation nowadays that cosmetic companies hardly dare to use it anymore.
It seems to us that squalane is in fashion and there is a reason for it. Chemically speaking, it is a saturated (no double bonds) hydrocarbon (a molecule consisting only of carbon and hydrogen), meaning that it's a nice and stable oily liquid with a long shelf life.
It occurs naturally in certain fish and plant oils (e.g. olive), and in the sebum (the oily stuff our skin produces) of the human skin. As f.c. puts it in his awesome blog post, squalane's main things are "emolliency, surface occlusion, and TEWL prevention all with extreme cosmetic elegance". In other words, it's a superb moisturizer that makes your skin nice and smooth, without being heavy or greasy.
Another advantage of squalane is that it is pretty much compatible with all skin types and skin conditions. It is excellent for acne-prone skin and safe to use even if you have fungi-related skin issues, like seborrhea or fungal acne.
The unsaturated (with double bonds) and hence less stable version of Squalane is Squalene, you can read about it here >>
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.
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.
The famous Vaseline or Petroleum Jelly. Just like mineral oil, it is also a by-product of refining crude oil, aka petroleum, and it is also a mixture of hydrocarbons but with bigger (C18-90+) carbon chain length.
The unique thing about petrolatum is that it is the most effective occlusive agent known today. While the occlusivity of mineral oil is in the same league as the occlusivity of plant oils, petrolatum is in a league of its own. It sits on top of the skin and hinders so-called transepidermal water loss (TEWL) like nothing else.
This comes in handy healing cracked lips or severely dry skin patches, though overdoing it (i.e. reducing TEWL by more than 40%) is not good as it can create a nice moist place for fungi and bacteria to grow.
As for petrolatum and safety, we can write here pretty much the exact same thing as we have written at mineral oil. There is no evidence whatsoever that cosmetic, USP grade petrolatum is carcinogenic. It also does not absorb into the skin but sits on top of it and that in itself greatly minimises health risks. It also has a long history of safe use, as it was first used as a skincare product more than 100 years ago, in 1872 to be precise.
It is also non-comedogenic, though its pure form is very heavy and greasy so combination and oily skin types might want to avoid it anyway.
Overall, it is the gold-standard occlusive agent known today and a tub of Vaseline comes in handy in any household to heal cracked lips or other severely dry skin patches.
Unless you live under a rock you must have heard about shea butter. It's probably the most hyped up natural butter in skincare today. It comes from the seeds of African Shea or Karite Trees and used as a magic moisturizer and emollient.
But it's not only a simple emollient, it regenerates and soothes the skin, protects it from external factors (such as UV rays or wind) and is also rich in antioxidants (among others vitamin A, E, F, quercetin and epigallocatechin gallate). If you are looking for rich emollient benefits + more, shea is hard to beat.
We all know honey as the sweet, gooey stuff that is lovely to sweeten a good cup of tea and we have good news about putting honey all over our skin. It is just as lovely on the skin as it is in the tea.
The great review article about honey in the Journal of Cosmetic Dermatology writes that it is arguably the oldest skincare ingredient and evidence from around 4500 BC mentions honey in some eye cream recipes. Chemically speaking, it is a bee-derived, supersaturated sugar solution. About 95% of honey dry weight is sugar and the other 5% consists of a great number of other minor components including proteins, amino acids, vitamins, enzymes, and minerals.
This unique and complex chemical composition gives honey a bunch of nice skin care properties: it is very moisturizing, has soothing and antioxidant abilities as well as significant antibacterial and antifungal magic powers. There is also a lot of empirical evidence with emerging scientific backup that honey dressing promotes the healing of wounds and burns.
One tricky thing about honey though, is that it can have lots of different floral sources and different types of honey have a somewhat different composition and thus somewhat different properties. For example, the darker the honey the richer it is in antioxidant phenolic compounds. Two special types of honey are acacia and manuka. The former is unique and popular because of its higher than usual fructose content that makes it more water-soluble and easier to stabilize in cosmetic formulas. The latter comes from the Leptospermum Scoparium tree native to New Zeland and its special thing is its extra strong antibacterial power due to a unique component called methylglyoxal.
Overall, honey is a real skin-goodie in pretty much every shape and form, and it is a nice one to spot on the ingredient list.
We don't have description for this ingredient yet.
A sugar beet-derived amino acid derivative with nice skin protection and moisturization properties. Betaine's special thing is being an osmolyte, a molecule that helps to control cell-water balance. It is also a natural osmoprotectant, meaning that it attracts water away from the protein surface and thus protects them from denaturation and increases their thermodynamic stability.
It also gives sensorial benefits to the formula and when used in cleansers, it helps to make them milder and gentler.
It’s the - sodium form - cousin of the famous NMF, hyaluronic 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".
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).
We don't have description for this ingredient yet.
The unfancy name for it is lye. It’s a solid white stuff that’s very alkaline and used in small amounts to adjust the pH of the product and make it just right.
For example, in case of AHA or BHA exfoliants, the right pH is super-duper important, and pH adjusters like sodium hydroxide are needed.
BTW, lye is not something new. It was already used by ancient Egyptians to help oil and fat magically turn into something else. Can you guess what? Yes, it’s soap. It still often shows up in the ingredient list of soaps and other cleansers.
Sodium hydroxide in itself is a potent skin irritant, but once it's reacted (as it is usually in skin care products, like exfoliants) it is totally harmless.
A big molecule created from repeated subunits (a polymer of acrylic acid) that magically converts a liquid into a nice gel formula. It usually has to be neutralized with a base (such as sodium hydroxide) for the thickening to occur and it creates viscous, clear gels that also feel nice and non-tacky on the skin. No wonder, it is a very popular and common ingredient. Typically used at 1% or less in most formulations.
A handy 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.
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. :))
A very common type of feared-by-everyone-mostly-without-scientific-reason paraben. It's a cheap, effective and well-tolerated ingredient to make sure the cosmetic formula does not go wrong too soon. Read more about parabens here >>
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| what‑it‑does | solvent |
| what‑it‑does | skin-identical ingredient | moisturizer/humectant |
| irritancy, com. | 0, 0 |
| what‑it‑does | emollient | solvent |
| irritancy, com. | 0, 0-2 |
| what‑it‑does | skin-identical ingredient | emollient |
| irritancy, com. | 0, 1 |
| what‑it‑does | moisturizer/humectant | solvent |
| irritancy, com. | 0, 1 |
| what‑it‑does | emollient |
| what‑it‑does | emollient |
| what‑it‑does | soothing | moisturizer/humectant | antimicrobial/antibacterial |
| what‑it‑does | emollient | moisturizer/humectant |
| what‑it‑does | moisturizer/humectant |
| what‑it‑does | skin-identical ingredient | moisturizer/humectant |
| irritancy, com. | 0, 0 |
| what‑it‑does | emulsifying | surfactant/cleansing |
| what‑it‑does | buffering |
| what‑it‑does | viscosity controlling |
| irritancy, com. | 0, 1 |
| what‑it‑does | chelating |
| what‑it‑does | preservative |
| irritancy, com. | 0, 0 |
| what‑it‑does | preservative |