Liquid Peptides
Ingredients overview
Highlights
Key Ingredients
Skim through
Medik8 Liquid PeptidesIngredients 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
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.
A four amino acid peptide with the amino sequence of glycine-glutamine-proline-arginine. It is attached to palmitic acid (a fatty acid) to increase oil solubility and skin penetration.
It works by reducing the production of the signal molecule, interleukin-6 (IL-6) which promotes inflammation in the skin and less inflammation means slower degradation of important things (like collagen) that results in younger looking skin for a longer time.
It works in synergy with its pal, Palmitoyl Tripeptide-1 in the famous Matrixyl 3000 complex. You can read some more about the famous duo here.
A really famous peptide that is part of Matrixyl 3000, the most sold peptide complex in the word. Before we go and find out what the big deal with Matrixyl 3000 is, let's just focus on Palmitoyl Tripeptide-1 itself for a bit.
It's a small three amino acid (they are the building blocks of all proteins) peptide with the amino sequence of glycine-histidine-lysine, or GHK. GHK is attached to palmitic acid (a fatty acid) to increase oil solubility and skin penetration.
The GHK part is the important one as it's a type I collagen fragment. When collagen naturally breaks down in the skin, the resulting peptide fragments signal to the skin that it should get to work and create some nice, new collagen. Adding in collagen fragment peptides, like GHK, might trick the skin into thinking that collagen has broken down and it's time to create some more.
Therefore, Palmitoyl Tripeptide-1 is believed to be able to stimulate collagen production in the skin, and more collagen means fewer wrinkles and younger looking skin.
In Matrixyl 3000, Palmitoyl Tripeptide-1 is coupled with Palmitoyl Tetrapeptide-7 and the duo works in synergy to reduce wrinkles and give younger looking skin. According to the manufacturer's in-vivo (made on real people) test, applying 3% Matrixyl 3000 twice a day for 2 months resulted in all of the following things:
- 39.4% reduction in surface occupied by deep wrinkles
- 32.9% reduction in main wrinkle density
- 19.9% reduction in main wrinkle average depth
- 16% improvement in roughness
- 16.2% in lifting effect
- 5.5% improvement in elasticity
- 15.5% improvement in skin tone
Manufacturer results, of course, always have to be taken with a pinch of salt, but if you like peptides, the Matryxil 3000 duo is one of the best-proven and most well-known ones and it's something that is worth trying.
We don't have description for this ingredient yet.
Heptapeptide-15 Palmitate is the targeting peptide (a short chain of amino acids) that is part of the encapsulated copper peptide technology trade named X50 Antiaging. This smart guy sits at the outer part of the encapsulation shell and seeks out the all-important collagen-producing cells in the middle layer of the skin called fibroblasts.
Once Heptapeptide-15 Palmitate binds to the receptors of the fibroblast, the cell internalizes the capsule, and the payload (in this case Copper Palmitoyl Heptapeptide-14) is released. Continue here to read what the payload peptide is doing once it arrives at its target, the fibroblast cell.
We don't have description for this ingredient yet.
It's a pretty new peptide trade-named MATRIXYL™ synthe’6. The manufacturer claims that it can boost the production of 6 major components of the skin matrix (collagen I, III, IV, fibronectin, hyaluronic acid and laminin 5) that result in more even skin and fewer wrinkles particularly on the forehead and crow's feet. Using 2% of the active for two months daily, women reported a decrease in wrinkles by 31% up to 100%.
Though its name does not reveal it, Carnosine is a peptide, a small, two amino acid (β-Ala-His) one. It is naturally present in high concentrations in muscle and brain tissues, but the one used in cosmetic products is biomimetic, meaning that it is synthetically produced in a lab to copy the natural thing.
A 2017 review paper on topical peptides writes about Carnosine that it is a "well-documented aqueous antioxidant with wound healing activity".
Other than that we can write about manufacturer-done in-vitro (in the lab, not on real people) studies that show Carnosine to have anti-glycation properties. Glycation is the not-so-nice process that happens when we bombard our body with too much sugar that results in damaged body proteins and eventually in more wrinkles.
Also, a manufacturer done in vitro study shows that carnosine might have collagen-boosing magic power. However, the 2017 research paper also mentions that even though Carnosine is a small molecule, it is water soluble and does not penetrate the skin past the top layers so we have some doubt if the collagen-boosting works in real life. We could find one anti-aging study made on real people that mentions Carnosine, but it was combined with a bunch of other anti-aging actives so it is pretty much impossible to know what Carnosine did or did not.
One last thing to mention is that there is also a manufacturer done clinical study (done on real people) that shows carnosine being effective against the damages caused by infrared (IR) radiation. (source)
If you see a cosmetic product that claims that it has "Botox-like effect" then two things are almost certain: one, the product overpromises and two, it contains Argireline.
So this one is the famous peptide that's marketed by its manufacturer as the "Botox in a jar". The basis for this claim is that it targets the same wrinkle forming mechanism (wrinkles caused by facial muscle movement) as Botox, but the way it works is very different. In addition, the extent to which it can prevent muscles from contracting (and to smooth wrinkles) is very different (otherwise why would anyone use still Botox?).
The manufacturer did several studies to prove that Argireline really works and it does (just not as well as Botox). In-vivo (made on real people) tests showed that using 10% Argireline solution around the eyes for 15 days decreased wrinkles depth by 17%, while a 5% Argireline formula applied for 28 days did almost the same with a decrease in wrinkle depth by 16.26%. A Spanish University also did some research and found that Argireline increased the level of skin moisturization and decreased both the depth and width of wrinkles "significantly".
This means, Acetyl Hexapeptide-8 does have some ability to smooth wrinkles (but not as well as Botox - sorry, if we sound like a broken record). Also, we have to agree with TruthInAging, that it's not a collagen builder and not a preventer of structural aging (think vitamin C, AHAs or retinol); it's just a quick fix. If you are looking for one, this could be your thing. If you are more of a "let's treat this aging thing properly" type, then it's probably not your thing.
A five amino-acid peptide that is claimed to target expression wrinkles that appear due to facial movements. Its effect is similar to the older and more famous Argireline peptide. They achieve similar results but in a different way.
The two together work in a synergistic way (the solution is trade named Argirelox) hindering the muscle contraction process in two different stages. The in-vivo (made on real people) test by the manufacturer showed that after 28 days 5% Leuphasyl alone reduced wrinkles by 11% and 5% Leuphasyl + 5% Argireline reduced wrinkles on average by 25% with max values up to 47%.
A tripeptide (three amino acids attached to each other: Lys-Val-Lys) that's claimed to protect and boost collagen and improve skin texture.
The manufacturer did an in-vivo (made on real people) study with 45 volunteers and found that used twice daily for 84 days 1% and 2.5% Syn-Coll reduces the appearance of wrinkles by 7 and 12% respectively. In another study (also by the manufacturer) with 33 female Chinese volunteers, 77% of the participants felt that Syn-Coll visibly improved the firmness and elasticity of the skin after 4 weeks. What's more, 60% of the participants also noticed a reduction in the look of the pore size also after 4 weeks of treatment.
A four amino acid (Glycine – Glutamic acid – Lysine – Glycine) peptide that belongs to the group of signal peptides that mimic skin-protein breakdown products to trick the skin into creating some nice new skin proteins, such as collagen (if this sentence is not clear, here is a bit longer and nicer explanation).
According to its manufacturer, Tetrapeptide-21 shows superior collagen, hyaluronic acid and fibronectin (all nice and important skin elements) boosting activity, and can smooth and minimize all kinds of wrinkles. The in-vitro data (made on human dermal fibroblast culture) showed that compared to Matrixyl (the first-generation Matrixyl peptide called Palmitoyl Pentapeptide-4), the collagen production in the presence of Tetrapeptide-21 was almost 2-fold higher (and about 2.5-fold vs the control). This data was confirmed by an in-vivo study that compared on 60 volunteers 0.5% Tego Pep 4-17 (10ppm of Tetrapeptide-21), 5% Tego Pep 4-17 (100ppm of Tetrapeptide-21) and 10% Matrixyl (10ppm of Palmitoyl Pentapeptide-4) and found that Tetrapeptide-21 performed better after 8 weeks for skin volume, roughness and elasticity.
The manufacturer also did another 60 people anti-wrinkle study with 4% Tego Pep 4-17 (compared to vehicle) where they have some nice before and after pictures showing visible-to-the-naked-eye wrinkle reduction around the eye area.
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).
A naturally occurring fructose polysaccharide found in the roots and rhizomes of several plants, for example, chicory. It is used in skincare for its prebiotic activity, meaning that it reduces the growth of bad bacteria in favor of friendly microorganisms naturally present on the skin.
A skin protecting ingredient obtained by enzymatic synthesis from natural sugars (sucrose and maltose). It's claimed to be a bio-selective substrate that protects and stimulates the beneficial microbial skin flora without doing the same with pathogens and undesirable flora. It also stimulates the antimicrobial peptide release by keratinocytes (skin cells).
We don't have description for this ingredient yet.
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.
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.
A type of bucket or donut-shaped molecule with a water-loving outer side and an oil-loving inner side that is used mostly to encapsulate other actives in cosmetics.
We don't have description for this ingredient yet.
It's a common little helper ingredient that helps water and oil to mix together. Also, it can help to increase the solubility of some other ingredients in the formula.
It’s a handy multi-tasking ingredient that gives the skin a nice, soft feel. At the same time, it also boosts the effectiveness of other preservatives, such as the nowadays super commonly used phenoxyethanol.
The blend of these two (caprylyl glycol + phenoxyethanol) is called Optiphen, which not only helps to keep your cosmetics free from nasty things for a long time but also gives a good feel to the finished product. It's a popular duo.
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.
A 100% plant derived, natural (Ecocert approved) multi-functional ingredient that has emollient and moisturizing properties, can work as a co-emulsifier (meaning that next to other emulsifiers it can help water and oil to mix) and even more importantly has a strong antimicrobial activity.
Thanks to this last thing, it allows a lower percentage of traditional preservative or it might even be able to completely replace them.
A naturally occurring floral component with a delicate scent that can mask the odor of other raw materials but is not noticeable in the final product. It also has remarkable antimicrobial and preservative boosting abilities and can help to create "preservative-free" formulas.
We don't have description for this ingredient yet.
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.
It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It’s not a strong one and doesn’t really work against bacteria, but more against mold and yeast. To do that it has to break down to its active form, sorbic acid. For that to happen, there has to be water in the product and the right pH value (pH 3-4).
But even if everything is right, it’s not enough on its own. If you see potassium sorbate you should see some other preservative next to it too.
BTW, it’s also a food preservative and even has an E number, E202.
A helper ingredient that helps to make the products stay nice longer, aka preservative. It works mainly against fungi.
It’s pH dependent and works best at acidic pH levels (3-5). It’s not strong enough to be used in itself so it’s always combined with something else, often with potassium sorbate.
A mild, natural preservative that usually comes to the formula together with its other mild preservative friends, such as Benzoic Acid and/or Dehydroacetic Acid. Btw, it's also used as a food 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.
It's one of the most commonly used thickeners and emulsion stabilizers. If the product is too runny, a little xanthan gum will make it more gel-like. Used alone, it can make the formula sticky and it is a good team player so it is usually combined with other thickeners and so-called rheology modifiers (helper ingredients that adjust the flow and thus the feel of the formula). The typical use level of Xantha Gum is below 1%, it is usually in the 0.1-0.5% range.
Btw, Xanthan gum is all natural, a chain of sugar molecules (polysaccharide) produced from individual sugar molecules (glucose and sucrose) via fermentation. It’s approved by Ecocert and also used in the food industry (E415).
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| what‑it‑does | solvent |
| what‑it‑does | skin-identical ingredient | moisturizer/humectant |
| irritancy, com. | 0, 0 |
| what‑it‑does | moisturizer/humectant | solvent |
| irritancy, com. | 0, 1 |
| what‑it‑does | cell-communicating ingredient |
| what‑it‑does | cell-communicating ingredient |
| what‑it‑does | cell-communicating ingredient |
| what‑it‑does | cell-communicating ingredient |
| what‑it‑does | antioxidant | cell-communicating ingredient |
| what‑it‑does | cell-communicating ingredient | moisturizer/humectant |
| what‑it‑does | cell-communicating ingredient |
| what‑it‑does | cell-communicating ingredient |
| what‑it‑does | cell-communicating ingredient |
| what‑it‑does | skin-identical ingredient | moisturizer/humectant |
| irritancy, com. | 0, 0 |
| what‑it‑does | soothing | moisturizer/humectant |
| irritancy, com. | 0, 0 |
| what‑it‑does | preservative |
| what‑it‑does | emulsifying | surfactant/cleansing |
| irritancy, com. | 0, 0 |
| what‑it‑does | moisturizer/humectant | emollient |
| what‑it‑does | buffering |
| what‑it‑does | preservative |
| what‑it‑does | moisturizer/humectant |
| what‑it‑does | perfuming | solvent |
| what‑it‑does | viscosity controlling |
| what‑it‑does | viscosity controlling |
| irritancy, com. | 0, 1 |
| what‑it‑does | preservative |
| what‑it‑does | preservative |
| what‑it‑does | preservative |
| what‑it‑does | preservative |
| what‑it‑does | viscosity controlling |