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Tink Caffeine + Allantoin Eye Contour Serum

Caffeine + Allantoin Eye Contour Serum

Caffeine & avocado oil eye serum
Uploaded by: ddaniels on

Tink Caffeine + Allantoin Eye Contour Serum
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. 

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. 

Avocado Oil - goodie
Also-called: Avocado Oil, Persea Americana Oil;Persea Gratissima Oil | What-it-does: antioxidant, emollient | Irritancy: 0 | Comedogenicity: 0-3

The oil coming from the pulp of one of the most nutritious fruits in the world, the avocado. It's loaded with the nourishing and moisturizing fatty acid, oleic (70%) and contains some others including palmitic (10%) and linoleic acid (8%). It also contains a bunch of minerals and vitamins A, E and D

Avocado oil has extraordinary skin penetration abilities and can nourish different skin layers. It's a very rich, highly moisturizing emollient oil that makes the skin smooth and nourished. Thanks to its vitamin E content it also has some antioxidant properties. As a high-oleic plant oil, it is recommended for dry skin

Also-called: Argan Oil | What-it-does: antioxidant, emollient

When it comes to cosmetic oils and hype, argan oil is for sure leading the way. Dubbed as the "liquid gold of Morocco", we have to admit we have some trouble determining why this oil enjoys such a special miracle status. Not that it's not good, it is good, even great but reading the research about argan and a bunch of other plant oils we just do not see the big, unique differentiating factor (though that might be our fault not reading enough, obvs.)

So, argan oil comes from the kernel of the argan fruit that comes from the argan tree that grows only in Morocco. The tree is slow growing and getting the oil is a hard job. The traditional process is that the ripe argan fruits fall from the tree, then goats eat them up and poop out the seeds. The seeds are collected and smashed with a stone to get the kernels inside. This part is the hard one as the seeds have extremely hard shells. Once the kernels are obtained, the oil is pressed out from them (the kernels contain about 50% oil).

As for skincare, argan oil is loaded with lots of skin goodies (but so are many other plant oils): it contains 80% nourishing and moisturizing unsaturated fatty acids, mainly oleic (38-50%), linoleic (28-38%) and palmitic (10-18%). It also contains a relatively large amount of antioxidant vitamin E (600-900 mg/kg, about twice as much as olive), small amounts of antioxidant phenols (including caffeic acid, ferulic acid, and epicatechin), as well as some rare sterols with soothing and anti-inflammatory properties. 

Thanks to all the above goodness in argan oil, it can greatly nourish and moisturize the skin and hair. It's also claimed to be able to neutralize collagen-damaging free radicals, help reduce scars, and revitalize and improve skin elasticity. You can even read that argan might help acne-prone skin, but being a high oleic oil, we would be careful with that

All in all, argan oil is a real goodie but we do not fully understand the special miracle status it enjoys.

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 >>

We don't have description for this ingredient yet.

What-it-does: viscosity controlling

A big molecule from repeated subunits that is used to form gel-like textures and create a film on the skin. 

What-it-does: emulsifying

We don't have description for this ingredient yet.

Caffeine - goodie
What-it-does: antioxidant, perfuming

Hello, our favorite molecule that helps us wake up in the morning and then keeps us going through the day. As a super well-known stimulant from coffee, tea and plenty of other soft drinks, Caffeine needs no introduction. So we will skip right to the part where we talk about what the hell it does in so-so many cosmetic products.

Looking at the research, we were surprised to find how versatile Caffeine is. It is a small, water-loving molecule with pretty good skin penetration abilties. Once in the skin, it has nice antioxidant properties, meaning that it reduces the formation of evil free radicals and it might even be useful in preventing UV-induced skin cancers. 

A well-known thing about Caffeine is that it improves the microcirculation of the blood vessels. Though conventional wisdom and anecdotal evidence says that this property is helpful for dark under-eye circles and puffy eyes, we have to mention that the double-blind research we have found about a 3% caffeine gel concluded that "the overall efficacy of the selected caffeine gel in reducing puffy eyes was not significantly different from that of its gel base."  But you know, the proof is in the pudding.

Another thing Caffeine is used for in body care products is its anti-cellulite effects. In theory, it can speed up the lipolysis process (the "fat burning"  by our cells) and stimulate the draining lymph system that might lead to the improvement of cellulite. But here again, the evidence that it actually makes a measurable, let alone visible,  improvement on actual human beings is limited (we could find only some animal skin studies or caffeine being combined with other actives). 

Last, but not least, we have to write about caffeine and hair growth. The theory is that it can inhibit the activity of the 5-α-reductase enzyme that plays an important role in hair loss and allows a renewed growth phase of the hair. We have found some recent and promising research to back this up. A 2017 study compared a 0.2% caffeine liquid with a 5% Minoxidil  (an FDA approved active to treat baldness) solution and found that  "a caffeine-based topical liquid should be considered as not inferior to minoxidil 5% solution in men with androgenetic alopecia", or English translation means that the caffeine liquid was pretty much as good as the FDA-approved Minoxidil stuff. Not bad!

Overall, we think that caffeine is a very versatile and biologically active ingredient. Even though some of its effects are more hyped up than backed up, it is still a nice to have on many ingredient lists. 

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.

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. 

We don't have description for this ingredient yet.

Also-called: Vitamin E Acetate;Tocopheryl Acetate | What-it-does: antioxidant | Irritancy: 0 | Comedogenicity: 0

It’s the most commonly used version of pure vitamin E in cosmetics. You can read all about the pure form here. This one is the so-called esterified version. 

According to famous dermatologist, Leslie Baumann while tocopheryl acetate is more stable and has a longer shelf life, it’s also more poorly absorbed by the skin and may not have the same awesome photoprotective effects as pure Vit E. 

Ferulic Acid - goodie

Ferulic Acid (FA) is a goodie that can be found naturally in plant cell walls. There is a lot of it especially in the bran of grasses such as rice, wheat and oats. 

FA - whose main job is to be an antioxidant - owes its fame to a 2005 research that discovered that adding in 0.5% FA to a 15% Vitamin C + 1% Vitamin E solution not only stabilizes the highly unstable, divaish Vit C, but it also doubles the photoprotection abilities of the formula. 

Couple of other studies show that FA just by itself is also a nice addition to cosmetic formulations: it can penetrate the skin (which is kind of important to do the job) and it has protecting properties against UV caused skin damage.

So if you spot it on the ingredient list be happy about it. :)

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: 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. 

Other than having a good safety profile and being quite gentle to the skin it has some other advantages too. It can be used in many types of formulations as it has great thermal stability (can be heated up to 85°C) and works on a wide range of pH levels (ph 3-10). 

It’s often used together with ethylhexylglycerin as it nicely improves the preservative activity of phenoxyethanol.

A white powdery thing that's the major component of glass and sand. In cosmetics, it’s often in products that are supposed to keep your skin matte as it has great oil-absorbing abilities. It’s also used as a helper ingredient to thicken up products or suspend insoluble particles. 

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.  

Also, if your skin is sensitive, fragrance is again not your best friend. It’s the number one cause of contact allergy to cosmetics. It’s definitely a smart thing to avoid with sensitive skin (and fragrance of any type - natural is just as allergic as synthetic, if not worse!). 

What-it-does: buffering

Citric acid comes from citrus fruits and is an AHA. If these magic three letters don’t tell you anything, click here and read our detailed description on glycolic acid, the most famous AHA. 

So citric acid is an exfoliant, that can - just like other AHAs - gently lift off the dead skin cells of your skin and make it more smooth and fresh. 

There is also some research showing that citric acid with regular use (think three months and 20% concentration) can help sun-damaged skin, increase skin thickness and some nice hydrating things called glycosaminoglycans in the skin. 

But according to a comparative study done in 1995, citric acid has less skin improving magic properties than glycolic or lactic acid. Probably that’s why citric acid is usually not used as an exfoliant but more as a helper ingredient in small amounts to adjust the pH of a formulation. 

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 antioxidant | emollient
irritancy, com. 0, 0-3
Avocado oil - a highly moisturizing, rich emollient oil that is loaded with fatty acids (oleic - 70%) and vitamin A, E and D. [more]
what‑it‑does antioxidant | emollient
Argan oil - the "liquid gold of Morocco" that contains 80% unsaturated fatty acids (oleic and linoleic mainly), and antioxidant vitamin E and phenols. It's highly nourishing and moisturizing both for skin and hair. [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 viscosity controlling
A big molecule from repeated subunits that is used to form gel-like textures and create a film on the skin.  [more]
what‑it‑does emulsifying
what‑it‑does antioxidant | perfuming
The well-known stimulant from coffee. It has nice antioxidant properties and can improve the microcirculation. Might be helpful for dark circles, puffy eyes, as well as cellulite and hair loss. [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 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 antioxidant
irritancy, com. 0, 0
A form of vitamin E that works as an antioxidant. Compared to the pure form it's more stable, has longer shelf life, but it's also more poorly absorbed by the skin. [more]
what‑it‑does antioxidant | antimicrobial/antibacterial
A great antioxidant that is most famous for stabilizing the highly unstable Vitamin C. It also doubles the photoprotection abilities of Vit C+E formulas. [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 preservative
Pretty much the current IT-preservative. It’s safe and gentle, and can be used up to 1% worldwide. [more]
what‑it‑does viscosity controlling
A white powdery thing that can mattify the skin and thicken up cosmetic products. [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 buffering
An AHA that comes from citrus fruits. It is usually used as a helper ingredient to adjust the pH of the formula. [more]