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Ketrel Tretinoin 0.05

Tretinoin 0.05

Tretinoin cream 0.05
Uploaded by: joeyknoef on

Ketrel Tretinoin 0.05
Ingredients explained

Tretinoin - superstar
Also-called: All-Trans-Retinoic Acid, Form of Retinoids | What-it-does: cell-communicating ingredient
  • Tretinoin (a metabolite of vitamin A) is the gold standard anti-aging ingredient that is also FDA-approved (and it's the only one so far!)
  • It's an all around skin issue fixer as it works at the skin cell level and makes your skin cells behave in a healthy and normal way
  • It makes the skin less wrinkled, firmer, smoother and tighter, everything you could want from an anti-aging ingredient
  • It's also an effective acne treatment. It normalizes keratinization and makes the pores produce less sebum
  • It's also a skin lightener though not as effective as gold-standard hydroquinone.
  • Side effects with tretinoin are very common. Irritation, skin flaking, redness, and drier skin are usual
  • Do not use tretinoin (or any form of retinoids) while pregnant
  • To minimize side effects introduce tretinoin slowly into your routine (see more how to use tips in geeky details)
Read all the geeky details about Tretinoin here >>

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. 

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.

What-it-does: emulsifying, surfactant/cleansing | Irritancy: 0 | Comedogenicity: 0

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

The number at the end refers to the oil-loving part and the bigger the number  the more emulsifying power it has. 20 is a weak emulsifier, rather called solubilizer used commonly in toners while 60 and 80 are more common in serums and creams.

This ingredient name is not according to the INCI-standard. :( What, why?!

A glycerin molecule combined with three fatty acids. It is the chemical structure of oils and does not denote an ingredient. 

Glycerol - superstar
Also-called: Glycerin | 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: Mineral Oil;Paraffinum Liquidum | What-it-does: emollient, solvent | Irritancy: 0 | Comedogenicity: 0-2

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.

Also-called: Butylated Hydroxy Toluene;BHT | What-it-does: antioxidant, preservative

It's the acronym for Butylated Hydroxy Toluene. It's a common synthetic antioxidant that's used as a preservative.

There is some controversy around BHT. It's not a new ingredient, it has been used both as a food and cosmetics additive since the 1970s. Plenty of studies tried to examine if it's a carcinogen or not. This Truth in Aging article details the situation and also writes that all these studies examine BHT when taken orally.

Also-called: BHA | What-it-does: antioxidant, preservative

It's the acronym for Butylated Hydroxy Anisole. It's a synthetic antioxidant that's used as a preservative

It's a somewhat controversial ingredient: The U.S. National Institutes of Health says that BHA is "reasonably anticipated to be a human carcinogen based on evidence of carcinogenicity in experimental animals" (source: wikipedia). But, and this is a big but: these experiments were made on animals and BHA was used in high doses as part of their diet. There is no evidence that the same is true when used in tiny amounts in cosmetics products. So you probably have nothing to worry about, but if you are a better safe than sorry type there are plenty of nice products without BHA to choose from. :) 

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. :))

What-it-does: preservative, perfuming | 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.

Also-called: lye | What-it-does: buffering

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.  

Also-called: Aqua;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. 

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

what‑it‑does cell-communicating ingredient
The gold-standard, and only FDA-approved anti-aging active ingredient. It works on the skin cell level and makes your skin cells behave in a healthy and normal way. It's not only an anti-aging miracle but is also an effective acne treatment and skin lightener. [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 viscosity controlling
irritancy, com. 0, 1
A handy white powder that magically converts a liquid into a nice gel formula. [more]
what‑it‑does emulsifying | surfactant/cleansing
irritancy, com. 0, 0
A common little helper ingredient that helps water and oil to mix together, aka emulsifier. [more]
A glycerin molecule combined with three fatty acids. It is the chemical structure of oils and does not denote an ingredient.  [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 emollient | solvent
irritancy, com. 0, 0-2
A clear, oily liquid that comes from refining crude oil. Even though it is a highly controversial ingredient, the scientific consensus is that it is a safe, non-irritating and effective emollient and moisturizer working mainly by occlusivity. [more]
what‑it‑does antioxidant | preservative
It's the acronym for Butylated Hydroxy Toluene. It's a common synthetic antioxidant that's used as a preservative.There is some controversy around BHT. [more]
what‑it‑does antioxidant | preservative
It's the acronym for Butylated Hydroxy Anisole. It's a synthetic antioxidant that's used as a preservative.  It's a somewhat controversial ingredient: The U.S. National Institutes of Health says that BHA is "reasonably anticipated to be a human carcinogen based on evidence of carcinogenicity in experimental animals" [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 preservative | perfuming
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 buffering
Lye - A solid white stuff that’s very alkaline and used in small amount to adjust the pH of the product.  [more]
what‑it‑does solvent
Normal (well kind of - it's purified and deionized) water. Usually the main solvent in cosmetic products. [more]