Follow us on our new Insta page »
Astra Siero Vitamin C

Siero Vitamin C

Serum suitable for those who want to prevent skin aging. Applied after daily facial cleansing and before cream, it completes the beauty treatment and helps keep the skin smooth, luminous and uniform.
Uploaded by: morgana on

Astra Siero Vitamin C
Ingredients explained

Also-called: Water | 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. 

We don't have description for this ingredient yet.

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 for dry skin at higher concentrations up to 20-40%
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

Also-called: Form of Vitamin C, SAP | What-it-does: antioxidant, anti-acne

The sodium salt form of skincare superstar, vitamin C. If you do not know what the big fuss about vitamin C is, you are missing out and you have to click here and read all the geeky details about it.

Pure vitamin C (aka ascorbic acid, AA) is great and all, but its lack of stability is a big challenge for the cosmetics industry. One solution is to create stable derivatives that can be absorbed into the skin, convert there to AA and do all the magic AA is proven to do (which is being an antioxidant, a collagen booster, and a skin brightener).

What-it-does: emollient, perfuming | Irritancy: 3 | Comedogenicity: 3-5

A  clear, colorless oil-like liquid that makes the skin feel smooth and nice (aka emollient) and it does so without it being greasy.

What's more, it can even reduce the heavy, greasy feel in products with high oil content. It's also fast-spreading meaning that it gives the formula a good, nice slip. It absorbs quickly into the skin and helps other ingredients to penetrate quicker and deeper. 

We don't have description for this ingredient yet.

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

We don't have description for this ingredient yet.

Thioctic Acid - goodie
Also-called: Alpha-Lipoic Acid | What-it-does: antioxidant

Alpha-Lipoic Acid (ALA) is a great antioxidant that's also part of the body's natural antioxidant system. It's soluble both in water-rich and lipid-rich environments so it's versatile and can interact with many types of evil oxidants as well as other nice antioxidants. 

ALA seems to be a great choice for topical use as studies show it can penetrate the skin rapidly where it's converted to DHLA (dihydrolipoic acid), an even more potent antioxidant molecule.  A nicely designed (we mean double-blind, placebo-controlled) 12-week study from 2003 confirmed that 5% ALA cream can decrease skin roughness and improve general signs of photoaging statistically significantly.  A slight catch, though, is that burning and warmth in the skin was quite a common side effect, especially in the first 4 weeks. 

Resveratrol - goodie
What-it-does: antioxidant

If you are looking for a reason why red wine is good for you, good news, you have found it! Resveratrol, aka the "red grape antioxidant" is the thing that's suspected to keep the French from coronary heart disease despite their not so healthy eating habits (such as high saturated fat intake).

So resveratrol, found in the seed and skin of the red grape (and berries), is a pretty well-known and well-studied molecule that has potent antioxidant, anti-inflammatory, and anticarcinogenic abilities. Most of the studies were done examining resveratrol's promising anti-cancer properties, but as for skin care, it shows a potent protective effect against UV-caused oxidative stress as well as promising effects against multiple types of skin cancer including the most severe one, melanoma (as an adjuvant therapy). 

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

What-it-does: emollient

A super common emollient that makes your skin feel nice and smooth. It comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. It’s a nice ingredient that just feels good on the skin, is super well tolerated by every skin type and easy to formulate with. No wonder it’s popular. 

Squalane - goodie
What-it-does: skin-identical ingredient, emollient | Irritancy: 0 | Comedogenicity: 1

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.

Also-called: Alphaflow | What-it-does: emollient, perfuming, solvent

A hydrocarbon-based emollient that can come in different viscosities from silky-light through satiny-smooth to luxurious, rich. It forms a non-occlusive film on the surface of the skin and brings gloss without greasiness to the formula. It's a very pure and hypoallergenic emollient that's also ideal for baby care products. 

Mandelic Acid - goodie
  • Mandelic acid is an AHA that comes from bitter almond
  • It can gently lift off dead surface skin cells and make the skin more smooth and even
  • It has antibacterial properties
  • It’s promising against acne and post inflammatory hyperpigmentation
  • It’s light sensitive, so choose a product with opaque packaging
Read all the geeky details about Mandelic Acid here >>

Also-called: Sepinov EMT 10 | What-it-does: viscosity controlling, emulsion stabilising

This long-named, polymer molecule (big molecule from repeated subunits) is a helper ingredient that's good at emulsifying and stabilizing oils into water-based formulas. It also acts as a thickening and gelling agent that creates nice, non-sticky and supple textures. It works over a very wide pH range (3-12) and can be used to thicken up low-ph formulas, such as exfoliants. Its recommended used range is 0.3-3%.

It's a helper ingredient that helps to thicken up formulas and form a nice gel texture. It leaves a rich, elegant feel with a velvety finish on the skin and works over a wide pH range.

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

What-it-does: moisturizer/humectant, solvent | Irritancy: 0 | Comedogenicity: 0
  • It's a helper ingredient that improves the freeze-thaw stability of products
  • It's also a solvent, humectant and to some extent a penetration enhancer
  • It has a bad reputation among natural cosmetics advocates but cosmetic scientists and toxicology experts do not agree (read more in the geeky details section)
Read all the geeky details about Propylene Glycol here >>

Lactic Acid - superstar
  • It’s the second most researched AHA after glycolic acid
  • It gently lifts off dead skin cells to reveal newer, fresher, smoother skin
  • It also has amazing skin hydrating properties
  • In higher concentration (10% and up) it improves skin firmness, thickness and wrinkles
  • Choose a product where you know the concentration and pH value because these two greatly influence effectiveness
  • Don’t forget to use your sunscreen (in any case but especially so next to an AHA product)
Read all the geeky details about Lactic Acid here >>

A common little helper ingredient that helps water and oil to mix together, aka emulsifier.

What-it-does: preservative

It’s pretty much the current IT-preservative. It’s safe and gentle, but even more importantly, it’s not a feared-by-everyone-mostly-without-scientific-reason paraben.

It’s not something new: it was introduced around 1950 and today it can be used up to 1% worldwide. It can be found in nature - in green tea - but the version used in cosmetics is synthetic. 

Parfum - icky
Also-called: Fragrance, Parfum;Parfum/Fragrance | What-it-does: perfuming

Exactly what it sounds: nice smelling stuff put into cosmetic products so that the end product also smells nice. Fragrance in the US and parfum in the EU is a generic term on the ingredient list that is made up of 30 to 50 chemicals on average (but it can have as much as 200 components!). 

If you are someone who likes to know what you put on your face then fragrance is not your best friend - there's no way to know what’s really in it.  

What-it-does: perfuming

Citronellol is a very common fragrance ingredient with a nice rose-like odor. In the UK, it’s actually the third most often listed perfume on the ingredient lists. 

It can be naturally found in geranium oil (about 30%) or rose oil (about 25%). 

Coumarin - icky
What-it-does: perfuming

A common fragrance ingredient that has a sweet, vanilla, nutty scent. When diluted it smells like freshly-mown hay.

It’s one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” on the label) because of allergen potential. Best to avoid if your skin is sensitive.

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 emulsifying | surfactant/cleansing
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 antioxidant | anti-acne
The sodium salt form of skincare superstar, vitamin C. If you do not know what the big fuss about vitamin C is, you are missing out and you have to click here and read all the geeky details about it. Pure vitamin C (aka ascorbic acid, AA) is great and all, but its lack of stability is a big challenge for the cosmetics industry. [more]
what‑it‑does emollient | perfuming
irritancy, com. 3, 3-5
A clear, colorless oil-like liquid that's used as a fast-spreading, non-greasy emollient. [more]
what‑it‑does emollient
irritancy, com. 0, 0
what‑it‑does antioxidant
Alpha-Lipoic Acid (ALA) is a great antioxidant that's also part of the body's natural antioxidant system. It's soluble both in water-rich and lipid-rich environments so it's versatile and can interact with many types of evil oxidants as well as other nice antioxidants. ALA seems to be a great choice for topical use as studies show it can penetrate the skin rapidl [more]
what‑it‑does antioxidant
A pretty well-known antioxidant that can be found in the skin and seeds of grapes, berries, and peanuts. It also has anti-inflammatory and anti-cancer (including skin cancer) magic properties. [more]
what‑it‑does emollient
A very common emollient that makes your skin feel nice and smooth. Comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. [more]
what‑it‑does skin-identical ingredient | emollient
irritancy, com. 0, 1
An emollient and natural moisturizer that can be found also in the sebum (oily stuff our skin produces). It leaves a nice non-greasy, non-heavy feeling on the skin. [more]
what‑it‑does emollient | perfuming | solvent
A hydrocarbon-based emollient that can come in different viscosities from silky-light to luxurious, rich. It forms a non-occlusive film on the surface of the skin. [more]
what‑it‑does exfoliant | antimicrobial/antibacterial
An AHA that comes from bitter almond. Its exfoliation action is slower but also safer than glycolic acid. It's also antibacterial and is a promising ingredient against acne and post inflammatory hyperpigmentation. [more]
what‑it‑does viscosity controlling
A helper ingredient that's good at stabilizing water-based formulas and also serves as a thickener. [more]
what‑it‑does viscosity controlling
A helper ingredient that helps to thicken up formulas and form a nice gel texture. It leaves a rich, elegant feel with a velvety finish on the skin.
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 moisturizer/humectant | solvent
irritancy, com. 0, 0
A common glycol that improves the freeze-thaw stability of products. It's also a solvent, humectant and to some extent a penetration enhancer. [more]
what‑it‑does exfoliant | moisturizer/humectant | buffering
A superstar AHA that not only exfoliates skin but is also a very good moisturizer. In higher concentration (10% and up) it can even improve skin firmness, thickness, and wrinkles. [more]
what‑it‑does emulsifying | surfactant/cleansing
A common little helper ingredient that helps water and oil to mix together, aka emulsifier.
what‑it‑does preservative
Pretty much the current IT-preservative. It’s safe and gentle, and can be used up to 1% worldwide. [more]
what‑it‑does perfuming
The generic term for nice smelling stuff put into cosmetic products so that the end product also smells nice. It is made up of 30 to 50 chemicals on average. [more]
what‑it‑does perfuming
A common fragrance ingredient with a nice rose-like smell. [more]
what‑it‑does perfuming
A common fragrance ingredient that has a sweet, vanilla, nutty scent. When diluted it smells like freshly-mown hay. [more]