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Some By Mi Yuja Niacin 30 Days Blemish Care Serum Mask

Yuja Niacin 30 Days Blemish Care Serum Mask

Intense brightening care Mask containing Moisturizing Yuja Serum. A daily mask that can turn your skin into a clear, dewy skin while Yuja ingredient filled with moisture and nutrients locks up moisture in your skin.
Uploaded by: hzelnuts on

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Ingredient name what-it-does irr., com. ID-Rating
Water solvent
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
Glycereth-26 moisturizer/​humectant, emollient, viscosity controlling 0, 0
Niacinamide (2%) cell-communicating ingredient, skin brightening, anti-acne, moisturizer/​humectant superstar
Citrus Junos Fruit Extract (10,000 Ppm)
Methylpropanediol solvent
1,2-Hexanediol solvent
Hydroxyacetophenone antioxidant
Arginine skin-identical ingredient goodie
Acrylates/C10-30 Alkyl Acrylate Crosspolymer viscosity controlling
Butylene Glycol moisturizer/​humectant, solvent, viscosity controlling 0, 1
Hydroxyethylcellulose viscosity controlling
Allantoin soothing 0, 0 goodie
Carbomer viscosity controlling 0, 1
Propanediol solvent, moisturizer/​humectant
Polyglyceryl-4 Caprate emulsifying
Polyglyceryl-6 Caprylate emulsifying
Adenosine cell-communicating ingredient goodie
Ethylhexylglycerin preservative
Disodium EDTA chelating, viscosity controlling
Citrus Tangerina (Tangerine) Peel Oil
Coptis Japonica Root Extract soothing, antioxidant goodie
Citrus Paradisi (Grapefruit) Peel Oil perfuming icky
Panthenol soothing, moisturizer/​humectant 0, 0 goodie
Tocopherol antioxidant 0-3, 0-3 goodie
Portulaca Oleracea Extract soothing, antioxidant goodie
Helianthus Annuus (Sunflower) Seed Oil emollient 0, 0 goodie
Pogostemon Cablin Oil perfuming
Cymbopogon Martini Oil
Arbutin antioxidant, skin brightening goodie
3-O-Ethyl Ascorbic Acid antioxidant, skin brightening goodie
Tricholoma Matsutake Extract
Scutellaria Baicalensis Root Extract soothing, antioxidant, antimicrobial/​antibacterial, moisturizer/​humectant goodie
Oryza Sativa (Rice) Extract abrasive/​scrub
Angelica Keiskei Leaf/Stem Extract
Panax Ginseng Root Extract antioxidant, emollient goodie
Rosmarinus Officinalis (Rosemary) Leaf Extract antioxidant, soothing, antimicrobial/​antibacterial goodie
Hyaluronic Acid skin-identical ingredient, moisturizer/​humectant goodie
Hydrolyzed Hyaluronic Acid moisturizer/​humectant goodie
Sodium Hyaluronate skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Glutathione
Limonene perfuming, solvent icky
Geraniol perfuming icky

Some By Mi Yuja Niacin 30 Days Blemish Care Serum Mask
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. 

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. 

Glycerin - superstar
Also-called: Glycerol | What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0
  • 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 at higher concentrations up to 20-40% (around 10% is a good usability-effectiveness sweet spot)
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

What-it-does: moisturizer/humectant, emollient, viscosity controlling | Irritancy: 0 | Comedogenicity: 0

It's a nice glycerin-based humectant and emollient that gives skin a smooth and luxurious feel.

Niacinamide (2%) - superstar
Also-called: vitamin B3, nicotinamide | What-it-does: cell-communicating ingredient, skin brightening, anti-acne, moisturizer/humectant
  • A multi-functional skincare superstar with several proven benefits for the skin
  • Great anti-aging, wrinkle smoothing ingredient used at 4-5% concentration
  • Fades brown spots alone or in combination with amino sugar, acetyl glucosamine
  • Increases ceramide synthesis that results in a stronger, healthier skin barrier and better skin hydration
  • Can help to improve several skin conditions including acne, rosacea, and atopic dermatitis
Read all the geeky details about Niacinamide here >>

We don't have description for this ingredient yet.

What-it-does: solvent

It's a type of glycol that - according to the manufacturer - is an extremely good replacement for other glycols like propylene or butylene glycol. Its main job is to be a solvent, but it has also very good antimicrobial properties and acts as a true preservative booster. Also helps with skin hydration without stickiness or tacky feel.

What-it-does: solvent

A really multi-functional helper ingredient that can do several things in a skincare product: it can bring a soft and pleasant feel to the formula, it can act as a humectant and emollient, it can be a solvent for some other ingredients (for example it can help to stabilize perfumes in watery products) and it can also help to disperse pigments more evenly in makeup products. And that is still not all: it can also boost the antimicrobial activity of preservatives

What-it-does: antioxidant

A handy multifunctional ingredient that works as a preservative booster, as well as an antioxidant and soothing agent

Arginine - goodie

A semi-essential (infants cannot synthesize it, but adults can) amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor, a skin hydrator and might also help to speed up wound healing

Arginine usually has a positive charge (cationic) that makes it substantive to skin and hair (those are more negatively charged surfaces) and an excellent film former.  Thanks to the positive charge, it also creates a complex with AHAs (AHAs like to lose a hydrogen ion and be negatively charged, so the positive and the negative ions attract each other) that causes a "time-release AHA effect" and reduces the irritation associated with AHAs

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: moisturizer/humectant, solvent, viscosity controlling | 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.

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. 

Also-called: HEC | What-it-does: viscosity controlling, emulsion stabilising

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. 

Allantoin - goodie
What-it-does: soothing | Irritancy: 0 | Comedogenicity: 0

Super common soothing ingredient. It can be found naturally in the roots & leaves of the comfrey plant, but more often than not what's in the cosmetic products is produced synthetically. 

It's not only soothing but it' also skin-softening and protecting and can promote wound healing.

What-it-does: viscosity controlling, emulsion stabilising | Irritancy: 0 | Comedogenicity: 1

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.

Also-called: Zemea | What-it-does: solvent, moisturizer/humectant

Propanediol is a natural alternative for the often used and often bad-mouthed propylene glycol. It's produced sustainably from corn sugar and it's Ecocert approved. 

It's quite a multi-tasker: can be used to improve skin moisturization, as a solvent, to boost preservative efficacy or to influence the sensory properties of the end formula. 

What-it-does: emulsifying

A water-loving emollient that is used as a solubilizer in water-based, toner-like formulas. Solubilizers are handy helper ingredients to dissolve small amounts of oil-loving materials (such as essential oils or fragrances) into watery liquids. Polyglyceryl-4 Caprate also has some emollient properties, making the skin feel nice and smooth. 

What-it-does: emulsifying

We don't have description for this ingredient yet.

Adenosine - goodie

Adenosine is an important little compound in our body that has a vital cell-signalling role. Research on smearing it on our face is also promising and shows so far a couple of things:

  • It can help with wound healing
  • It’s a good anti-inflammatory agent
  • It might even help with skin’s own collagen production and improve skin firmness and elasticity
  • It helps with barrier repair and protection
  • It might be even useful for the hair helping with hair thickness and hair growth
What-it-does: preservative, deodorant

If you have spotted ethylhexylglycerin on the ingredient list, most probably you will see there also the current IT-preservative, phenoxyethanol. They are good friends because ethylhexylglycerin can boost the effectiveness of phenoxyethanol (and other preservatives) and as an added bonus it feels nice on the skin too.

Also, it's an effective deodorant and a medium spreading emollient

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.

It is typically used in tiny amounts, around 0.1% or less.

Also-called: Tangerine Oil

We don't have description for this ingredient yet.

Also-called: Japanese Goldthread Root Extract | What-it-does: soothing, antioxidant

The extract coming from the root of the traditional medicinal herb, Coptis Japonica or Japanese Goldthread. The plant is used traditionally in East Asia for its anti-inflammatory, antioxidant and antimicrobial abilities.

Other than that, there is also an abstract from the International Journal of Cosmetic Science that found Coptis Japonica Root Extract and its active component called berberine to show potent inhibition of triglyceride (aka fat) accumulation and subcutaneous preadipocytes (the cells that become later fat cells) differentiation meaning that Goldthread Extract might also be useful in slimming and anti-cellulite products.

Also-called: Pink Grapefruit Peel Oil | What-it-does: perfuming

The essential oil coming from the peel of the pink grapefruit. In general, the main component of citrus peel oils is limonene (around 90% for grapefruit peel), a super common fragrant ingredient that makes everything smell nice (but counts as a frequent skin sensitizer). Similar to other essential oils, grapefruit peel has also antibacterial and antifungal acitivity

Other than that, citrus peels contain the problematic compounds called furanocoumarins that make them (mildly) phototoxic. So be careful with grapefruit peel oil, especially if it's in a product for daytime use.  

Panthenol - goodie
Also-called: Pro-Vitamin B5 | What-it-does: soothing, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

An easy-to-formulate, commonly used, nice to have ingredient that’s also called pro-vitamin B5. As you might guess from the “pro” part, it’s a precursor to vitamin B5 (whose fancy name is pantothenic acid). 

Its main job in skincare products is to moisturise the skin. It’s a humectant meaning that it can help the skin to attract water and then hold onto it. There is also research showing that panthenol can help our skin to produce more lovely lipids that are important for a strong and healthy skin barrier. 

Another great thing about panthenol is that it has anti-inflammatory and skin protecting abilities. A study shows that it can reduce the irritation caused by less-nice other ingredients (e.g. fragrance, preservatives or chemical sunscreens) in the product.

Research also shows that it might be useful for wound healing as it promotes fibroblast (nice type of cells in our skin that produce skin-firming collagen) proliferation. 

If that wasn’t enough panthenol is also useful in nail and hair care products. A study shows that a nail treatment liquide with 2% panthenol could effectively get into the nail and significantly increase the hydration of it.

As for the hair the hydration effect is also true there. Panthenol might make your hair softer, more elastic and helps to comb your hair more easily. 

Tocopherol - goodie
Also-called: Vitamin E | What-it-does: antioxidant | Irritancy: 0-3 | Comedogenicity: 0-3
  • Primary fat-soluble antioxidant in our skin
  • Significant photoprotection against UVB rays
  • Vit C + Vit E work in synergy and provide great photoprotection
  • Has emollient properties
  • Easy to formulate, stable and relatively inexpensive
Read all the geeky details about Tocopherol here >>

Also-called: Purslane Extract | What-it-does: soothing, antioxidant

Portulaca Oleracea is a nice succulent with bright yellow flowers and edible nutritious vegetables. It's a famous plant in Korean traditional medicine to treat infection and irritated skin.

Modern research confirms that it's loaded with skin-goodies: it's the richest green plant source of omega-3 fatty acids (α-linolenic acid), contains NMFs (polysaccharides and amino acids),  vitamins (β-carotene), minerals, and antioxidants (yellow betaxanthins and reddish betacyanins). Thanks to all its beneficial components, Purslane Extract has several magic properties: it's a great anti-inflammatory and antioxidant agent and also has wound healing abilities

Also-called: Sunflower Oil | What-it-does: emollient | Irritancy: 0 | Comedogenicity: 0

Sunflower does not need a big intro as you probably use it in the kitchen as cooking oil, or you munch on the seeds as a healthy snack or you adore its big, beautiful yellow flower during the summer - or you do all of these and probably even more. And by even more  we mean putting it all over your face as sunflower oil is one of the most commonly used plant oils in skincare.

It’s a real oldie: expressed directly from the seeds, the oil is used not for hundreds but thousands of years. According to The National Sunflower Association, there is evidence that both the plant and its oil were used by American Indians in the area of Arizona and New Mexico about 3000 BC. Do the math: it's more than 5000 years – definitely an oldie.

Our intro did get pretty big after all (sorry for that), so let's get to the point finally: sunflower oil - similar to other plant oils - is a great emollient that makes the skin smooth and nice and helps to keep it hydrated. It also protects the surface of the skin and enhances the damaged or irritated skin barrier. Leslie Bauman notes in Cosmetic Dermatology that one application of sunflower oil significantly speeds up the recovery of the skin barrier within an hour and sustains the results 5 hours after using it.

It's also loaded with fatty acids (mostly linoleic (50-74%)  and oleic (14-35%)). The unrefined version (be sure to use that on your skin!) is especially high in linoleic acid that is great even for acne-prone skin. Its comedogen index is 0, meaning that it's pretty much an all skin-type oil

Truth be told, there are many great plant oils and sunflower oil is definitely one of them.

Also-called: Patchouli Essential Oil;Pogostemon Cablin Leaf Oil | What-it-does: perfuming

If you are into perfumes, you must know patchouli as an important essential oil in the perfume industry. It boasts a pleasant woody, earthy and camphoraceous scent and has fixative properties (makes the fragrance long-lasting).

Its composition is pretty unique: it does not contain any of the EU's 26 most common fragrance allergens, but its most important components are patchoulol (30%) and alpha-patchoulene (6%) which are responsible for its aroma and antifungal properties.

Among essential oils, the allergen profile of patchouli counts as pretty good (much better than ylang-ylang or lemongrass oils), but if your skin is sensitive, it's still best to avoid it.

Also-called: Palmarosa Oil

We don't have description for this ingredient yet.

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.)

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: Form of Vitamin C, 3-O-Ethyl Ascorbate, EAC;Ethyl Ascorbic Acid | What-it-does: antioxidant, skin brightening

A very stable and promising form of the skincare superstar, Vitamin C. If you do not know why Vitamin C is such a big deal in skin care, you can catch up here. In short, Vitamin C has three proven magic abilities: antioxidant, collagen booster, and skin brightener. The problem, though, is that it's very unstable, turns brown and becomes ineffective in no time (after a few month) and the cosmetics industry is trying to come up with smart derivatives that are stable and have the magic properties of pure Vitamin C. 

Ethyl Ascorbic Acid or EAC for short is an "etherified derivative of ascorbic acid" that consists of vitamin C and an ethyl group bound to the third carbon position. This makes Vitamin C very stable and soluble in both water and oil.

However, for a Vitamin C derivative to work it's not enough just to be stable, they also have to be absorbed into the skin and be converted there to pure Vitamin C. We have good news regarding the absorption: on top of manufacturer claims, there is some data (animal study) demonstrating in can get into the skin, and it seems to be better at it than Ascorbyl Glucoside, another vitamin C derivative.

Regarding conversion, we can cite only a manufacturers claim saying that EAC is metabolized in the skin into pure ascorbic acid (and the ascorbic acid content of EAC is very high - 86,4% - compared to the usual 50-60% Vitamin C content of other derivatives). 

As for the three magic abilities of Vitamin C, we again mostly have only the manufacturer's claims, but at least those are very promising. EAC seems to have both an antioxidant and anti-inflammatory effect, and it's claimed to be able to boost the skin's collagen production. The strong point of EAC though is skin brightening. On top of manufacturer claims, there is also clinical in-vivo (tested on real people) data showing that 2% EAC can improve skin tone and whiten the skin. 

Overall, Ethyl Ascorbic Acid is a very promising but not a fully proven Vitamin C derivative. It's worth a try, especially if you are after Vitamin C's skin-brightening effects. 

We don't have description for this ingredient yet.

Also-called: Skullcap Root Extract | What-it-does: soothing, antioxidant, antimicrobial/antibacterial, astringent, moisturizer/humectant

A traditional Chinese herbal medicine loaded with potent antioxidant and anti-inflammatory flavonoids such as baicalin, baicalein, and wogonin.

If that would not be enough, Skullcap Root is also claimed to have antimicrobial and antifungal properties (also against P.acnes and Malassezia furfur) as well as some skin-brightening activity. A multi-functional skin-goodie.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

Also-called: True Ginseng, Ginseng, Korean Ginseng | What-it-does: antioxidant, emollient

A  traditional Korean medicine used for more than 2000 years. Regarding skin care, its main thing seems to be enhancing skin nutrition and metabolism as a result of improving blood circulation.

It also contains biologically active components referred to as ginseng saponins (ginsenosides) that have potent antioxidant properties

Also-called: Rosemary Leaf Extract | What-it-does: antioxidant, soothing, antimicrobial/antibacterial

The extract coming from the lovely herb, rosemary. It contains lots of chemicals, including flavonoids, phenolic acids, and diterpenes. Its main active is rosmarinic acid, a potent antioxidant, and anti-inflammatory. It has also anti-bacterial, astringent and toning properties. 

The leaves contain a small amount of essential oil (1-2%) with fragrant components, so if you are allergic to fragrance, it might be better to avoid it. 

  • It’s naturally in our skin and behaves there like a sponge
  • It can bind up to 1000 times its own weight in water
  • It is a big molecule from repeated subunits (polymer) so different molecular weight versions exist (unfortunately there is no way to determine MW from INCI list only)
  • High-molecular-weight-HA (>500 kDa) is an excellent surface hydrator, skin protectant and can act as an osmotic pump helping water-soluble actives to penetrate deeper into the skin
  • Low-molecular-weight-HA (< 500 kDa) can hydrate the skin somewhat deeper though it is still a big molecule and works mainly in the epidermis (outer layer of the skin)
  • Low-molecular-weight-HA might also help the skin to repair itself by increasing its self-defense (~ 200kDa used in the study)
  • Ultra-low-molecular-weight-HA (<50kDa) is a controversial ingredient and might work as a pro-inflammatory signal molecule
Read all the geeky details about Hyaluronic Acid here >>

What-it-does: moisturizer/humectant

Hydrolyzed Hyaluronic Acid is a low molecular weight, chemically chopped up version of the naturally big molecule and current IT-moisturizer, Hyaluronic Acid (HA). 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 retain water, making it plump and elastic. As HA is a polymer, the subunits can be repeated many times (as a high-molecular-weight version), or just a few times (as a low-molecular-weight version).

We wrote in detail at HA about how different molecular weight versions do different things both as a component of the skin and as a skincare ingredient, so click here and read about all the details. Hydrolyzed Hyaluronic Acid can also come in different molecular-weight versions with different properties:

  • 100-300 kDa version: apart from moisturizing, this size might also help the skin to repair itself by increasing its self-defense. It is also claimed to boost the wound healing process and is especially helpful for sensitive skin types (acne, rosacea, inflammation-related skin diseases). 
  • 50k Da version: this is the size that is claimed to be able to absorb into the skin and plump up wrinkles, so it is used mainly as an "anti-aging ingredient" 
  • below 50k, around 10k Da version: there is a Japanese version trade named Hyalo-Oligo that has only a 10k molecular weight and is claimed to penetrate the skin very well, have a unique touch and give deep and long-lasting moisturization. Based on the Evonik-research and the natural role of LMW-HA in the body working as a pro-inflammatory signal molecule, this ultra-low molecular weight version is a controversial ingredient

If you wanna become a real HA-and-the-skin expert, you can read much 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: 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". 

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.

Limonene - icky
What-it-does: perfuming, solvent, deodorant

A super common and cheap fragrance ingredient. It's in many plants, e.g. rosemary, eucalyptus, lavender, lemongrass, peppermint and it's the main component (about 50-90%) of the peel oil of citrus fruits.

It does smell nice but the problem is that it oxidizes on air exposure and the resulting stuff is not good for the skin. Oxidized limonene can cause allergic contact dermatitis and counts as a frequent skin sensitizer

Limonene's nr1 function is definitely being a fragrance component, but there are several studies showing that it's also a penetration enhancer, mainly for oil-loving components.

All in all, limonene has some pros and cons, but - especially if your skin is sensitive - the cons probably outweigh the pros.  

Geraniol - icky
What-it-does: perfuming

Geraniol is a common fragrance ingredient. It smells like rose and can be found in rose oil or in small quantities in geranium, lemon and many other essential oils. 

Just like other similar fragrance ingredients (like linalool and limonene) geraniol also oxidises on air exposure and becomes allergenic. Best to avoid if you have sensitive skin.

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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 skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
A real oldie but a goodie. Great natural moisturizer and skin-identical ingredient that plays an important role in skin hydration and general skin health. [more]
what‑it‑does moisturizer/humectant | emollient | viscosity controlling
irritancy, com. 0, 0
It's a nice glycerin-based humectant and emollient that gives skin a smooth and luxurious feel.
what‑it‑does cell-communicating ingredient | skin brightening | anti-acne | moisturizer/humectant
A multi-functional skincare superstar that has clinically proven anti-aging, skin lightening, anti-inflammatory and barrier repair properties. [more]
what‑it‑does solvent
A type of glycol. Its main job is to be a solvent, but it has also very good antimicrobial properties and acts as a true preservative booster. [more]
what‑it‑does solvent
A multi-functional helper ingredient that acts as a humectant and emollient. It's also a solvent and can boost the effectiveness of preservatives. [more]
what‑it‑does antioxidant
A handy multifunctional ingredient that works as a preservative booster, as well as an antioxidant and soothing agent.
what‑it‑does skin-identical ingredient
An amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor and might also help to speed up wound healing.  [more]
what‑it‑does viscosity controlling
A common helper ingredient that stabilizes emulsions and helps to thicken up products. [more]
what‑it‑does moisturizer/humectant | solvent | viscosity controlling
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 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 soothing
irritancy, com. 0, 0
Super common soothing ingredient. It can be found naturally in the roots & leaves of the comfrey plant, but more often than not what's in the cosmetic products is produced synthetically. It's not only soothing but it' [more]
what‑it‑does viscosity controlling
irritancy, com. 0, 1
A handy white powder that magically converts a liquid into a nice gel formula. [more]
what‑it‑does solvent | moisturizer/humectant
A natural corn sugar derived glycol. It can be used to improve skin moisturization, as a solvent, to boost preservative efficacy or to influence the sensory properties of the end formula. [more]
what‑it‑does emulsifying
A water-loving emollient that is used as a solubilizer in water-based, toner-like formulas. Solubilizers are handy helper ingredients to dissolve small amounts of oil-loving materials (such as essential oils or fragrances) into watery liquids. [more]
what‑it‑does emulsifying
what‑it‑does cell-communicating ingredient
An important compound in our body that has a vital cell-signalling role. It is wound healing, anti-inflammatory and can help with barrier repair. [more]
what‑it‑does preservative
It can boost the effectiveness of phenoxyethanol (and other preservatives) and as an added bonus it feels nice on the skin too. [more]
what‑it‑does chelating | viscosity controlling
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 soothing | antioxidant
The extract coming from the root of the traditional medicinal herb, Coptis Japonica or Japanese Goldthread. The plant is used traditionally in East Asia for its anti-inflammatory, antioxidant and antimicrobial abilities. Other than that, there is also an abstract from the International Journal of Cosmetic Science that found Coptis Japonica Root Extract and its active component called b [more]
what‑it‑does perfuming
The essential oil coming from the peel of the pink grapefruit. Its main component is limonene, a super common fragrant ingredient that makes everything smell nice. [more]
what‑it‑does soothing | moisturizer/humectant
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Pro-Vitamin B5 is a goodie that moisturises the skin, has anti-inflammatory, skin protecting and wound healing properties. [more]
what‑it‑does antioxidant
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Pure Vitamin E. Great antioxidant that gives significant photoprotection against UVB rays. Works in synergy with Vitamin C. [more]
what‑it‑does soothing | antioxidant
Purslane Extract - a traditional Korean medicinal plant with skin-soothing, antioxidant and wound healing abilities. [more]
what‑it‑does emollient
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Sunflower Oil - it's a great emollient that protects & enhances the skin barrier. [more]
what‑it‑does perfuming
Patchouli essential oil that has a woody, earthy and camphoraceous scent and also has fixative properties. Also has fixative and antifungal properties. [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 antioxidant | skin brightening
A stable form of Vitamin C, whose strong point is skin-brightening. It might also have antioxidant, anti-inflammatory and collagen boosting abilities. [more]
what‑it‑does soothing | antioxidant | antimicrobial/antibacterial | moisturizer/humectant
A traditional Chinese herbal medicine loaded with potent antioxidant and anti-inflammatory flavonoids such as baicalin, baicalein, and wogonin.If that would not be enough, Skullcap Root is also claimed to have antimicrobial and antifungal properties (also against P.acnes and Malassezia furfur) as well  [more]
what‑it‑does abrasive/scrub
what‑it‑does antioxidant | emollient
Ginseng - A traditional Korean medicine that has antioxidant properties, and is known to improve blood circulation. [more]
what‑it‑does antioxidant | soothing | antimicrobial/antibacterial
Rosemary leaf extract - Its main active is rosmarinic acid, a potent antioxidant, and anti-inflammatory. It has also anti-bacterial, astringent and toning properties. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
A famous natural moisturizing factor that can bind up to 1000 times its own weight in water. Works as an excellent surface hydrator in skincare. [more]
what‑it‑does moisturizer/humectant
Hydrolyzed Hyaluronic Acid is a low molecular weight, chemically chopped up version of the naturally big molecule and current IT-moisturizer, Hyaluronic Acid (HA). The TL; [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 perfuming | solvent
A super common fragrance ingredient found naturally in many plants including citrus peel oils, rosemary or lavender. It autoxidizes on air exposure and counts as a common skin sensitizer. [more]
what‑it‑does perfuming
A common fragrance ingredient that smells like rose and can be found in rose oil. [more]