Rejuvenate Daily Serum
Intraceuticals Rejuvenate Daily SerumIngredients 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 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.
A corn sugar derived, water-soluble, pale yellow syrup, that nicely moisturizes the skin. It has a light and smooth skin feel, it is non-tacky, and it can improve the after-feel of the formula. It is also mild and gentle, popular in sensitive skin formulas.
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.
Another advantage of squalane is that it is pretty much compatible with all skin types and skin conditions. It is excellent for acne-prone skin and safe to use even if you have fungi-related skin issues, like seborrhea or fungal acne.
The unsaturated (with double bonds) and hence less stable version of Squalane is Squalene, you can read about it here >>
Probably the most common silicone of all. It is a polymer (created from repeating subunits) molecule and has different molecular weight and thus different viscosity versions from water-light to thick liquid.
As for skincare, it makes the skin silky smooth, creates a subtle gloss and forms a protective barrier (aka occlusive). Also, works well to fill in fine lines and wrinkles and give skin a plump look (of course that is only temporary, but still, it's nice). There are also scar treatment gels out there using dimethicone as their base ingredient. It helps to soften scars and increase their elasticity.
As for hair care, it is a non-volatile silicone meaning that it stays on the hair rather than evaporates from it and smoothes the hair like no other thing. Depending on your hair type, it can be a bit difficult to wash out and might cause some build-up (btw, this is not true to all silicones, only the non-volatile types).
A common functional ingredient that helps to keep the oil-loving and water-loving ingredients together (emulsifier), stabilizes and thickens the products.
Chemically speaking, it is ethoxylated Cetearyl alcohol, meaning that some ethylene oxide is added to the fatty alcohol to increase the water-soluble part in the molecule. The result is that the mainly oil soluble, emollient fatty alcohol is converted to an emulsifier molecule that keeps oil and water mixed in creams. The number in the name of Ceteareth emulsifiers refers to the average number of ethylene oxide molecules added and 20 makes a good emulsifier.
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.
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).
- Green tea is one of the most researched natural ingredients
- The active parts are called polyphenols, or more precisely catechins (EGCG being the most abundant and most active catechin)
- There can be huge quality differences between green tea extracts. The good ones contain 50-90% catechins (and often make the product brown and give it a distinctive smell)
- Green tea is proven to be a great antioxidant, UV protectant, anti-inflammatory, anticarcinogenic and antimicrobial
- Because of these awesome properties green tea is a great choice for anti-aging and also for skin diseases including rosacea, acne and atopic dermatitis
The extract coming from the juice containing leaves of the Aloe vera plant. It's usually a hydroglycolic extract (though oil extract for the lipid parts also exists) that has similar moisturizing, emollient and anti-inflammatory properties as the juice itself. We have written some more about aloe here.
The extract coming from ginger, the lovely spice that we all know from the kitchen. It is also a medicinal plant used both in Chinese and Ayurvedic medicine for pretty much everything you can imagine (muscular pain, sore throat, nausea, fever or cramps, just to give a few examples).
As for ginger and skincare, the root extract contains the biologically active component called gingerol that has potent antioxidant and anti-inflammatory properties. Combined with Bisabolol, the duo works synergistically to sooth the skin and take down redness.
Other than that, ginger also contains moisturizing polysaccharides, amino acids, and sugars, and it is also quite well known to increase blood circulation and have a toning effect.
Last but not least, Ginger also has some volatile, essential oil compounds (1-3%). Those are mostly present in ginger oil, but small amounts might be in the extract as well (around 0.5% based on manufacturer info).
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).
SAP (the vit C derivative, not the enterprise software, obvs) is a promising derivative that has great stability up to pH 7. The challenge with it though is skin penetration. Unfortunately, it seems to be limited, or to quote a great article from the Journal of Cosmetic Dermatology "topically applied ascorbyl phosphate salts are, at very best, poorly absorbed in comparison with AA". Regarding conversion to AA, there seems to be no data about it, so we can neither deny nor confirm it.
We have better news regarding the three magic abilities of vitamin C: there is in-vivo (tested on real people) data showing that SAP does have photo-protective (aka antioxidant) properties, though less than pure AA. SAP might also aid collagen boosting; in-vitro (made in the lab) data shows that it works, but is less effective than another vitamin C derivative, called MAP (that seems to be as effective as pure AA). As for skin-brightening, there is a trade publication with in-vivo data showing that SAP can fade brown spots.
Another thing SAP might be able to do is to help with acne. A 2005 study showed in vitro (in test tubes) that 1% SAP has a strong antimicrobial activity on evil acne causing P. acnes and it also showed in vivo (on real people) that 5% SAP can strongly improve the inflammatory and non-inflammatory lesions of acne vulgaris. In fact, the results were comparable or even slightly better than with 5% benzoyl peroxide.
And there is even more regarding SAP and acne. A nice double-blind study from 2009 showed that 5% SAP reduced the inflammatory lesions by 20.14% and 48.82% within 4 and 8 weeks respectively and when combined with 0.2% retinol the results were even better. With this combination treatment, the improvement was 29.28% after 4 weeks and 63.10% after 8 weeks of application.
Aside from research studies, anecdotal evidence also supports SAP being a promising vitamin C derivative. One of the best-selling (vitamin C) serums in Sephora is the Ole Henriksen Truth Serum, while on Amazon it's the OzNaturals Vitamin C 20 Serum. Another popular choice is the Mad Hippie Vitamin C serum, and all of these contain vitamin C in the form of SAP.
Overall, we think SAP is a goody! In terms of anti-aging, it's probably not as effective as pure Ascorbic Acid, but it's totally worth a try. However, if your skin is acne-prone, SAP is your form of Vitamin C and it's a must-try.
It's an ester form of vitamin A (retinol + palmitic acid) that belongs to the "retinoid family". The retinoid family is pretty much the royal family of skincare, with the queen being the FDA-approved anti-aging ingredient tretinoin. Retinol is also a very famous member of the family, but it's like Prince William, two steps away from the throne. Retinyl palmitate will be then little Prince George, quite far (3 steps) away from the throne.
By steps, we mean metabolic steps. Tretinoin, aka retinoic acid, is the active ingredient our skin cells can understand and retinyl palmitate (RP) has to be converted by our metabolic machinery to actually do something. The conversion is a 3 step one and looks like this:
retinyl palmitate --> retinol -- > retinaldehyde --> all-trans-retinoic acid
As we wrote in our lengthy retinol description the problem is that the conversion is not terribly effective. The evidence that RP is still an effective anti-aging ingredient is not very strong, in fact, it's weak. Dr. Leslie Baumann in her fantastic Cosmetic Dermatology book writes that RP is topically ineffective.
What's more, the anti-aging effectiveness is not the only questionable thing about RP. It also exibits questionable behaviour in the presence of UV light and was the center of a debate between the non-profit group, EWG (whose intentions are no doubt good, but its credibility is often questioned by scientists) and a group of scientists and dermatologists lead by Steven Q. Wang, MD, director of dermatologic surgery at Memorial-Sloan Kettering Cancer Centre.
Dr. Leslie Baumann wrote a great review of the debate and summarized the research available about retinyl palmitate here. It seems that there is a study showing RP being photo protective against UVB rays but there is also a study showing RP causing DNA damage and cytotoxicity in association with UVA.
We think that the truth lies somewhere in the middle, and we agree with Dr. Baumann's conclusion: "sufficient evidence to establish a causal link between RP and skin cancer has not been produced. Nor, I’m afraid, are there any good reasons to recommend the use of RP". We would add especially during the day!
Bottom line: If you wanna get serious about retinoids, RP is not your ingredient (retinol or tretinoin is!). However, if you use a product that you like and it also contains RP, there is no reason to throw it away. If possible use it at night, just to be on the safe side.
- 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
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.
It's one of the active parts of Chamomile that contains about 30% of bisabolol. It's a clear oily fluid that is used in skincare as a nice anti-inflammatory and soothing ingredient.
- 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
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.
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).
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.
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.
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 even less.
It’s a little helper ingredient that helps to set the pH of a cosmetic formulation to be just right. It’s very alkaline (you know the opposite of being very acidic): a 1% solution has a pH of around 10.
It does not have the very best safety reputation but in general, you do not have to worry about it.
What is true is that if a product contains so-called N-nitrogenating agents (e.g.: preservatives like 2-Bromo-2-Nitropropane-1,3-Diol, 5-Bromo-5-Nitro- 1,3-Dioxane or sodium nitrate - so look out for things with nitro, nitra in the name) that together with TEA can form some not nice carcinogenic stuff (that is called nitrosamines). But with proper formulation that does not happen, TEA in itself is not a bad guy.
But let’s assume a bad combination of ingredients were used and the nitrosamines formed. :( Even in that case you are probably fine because as far as we know it cannot penetrate the skin.
But to be on the safe side, if you see Triethanolamine in an INCI and also something with nitra, nitro in the name of it just skip the product, that cannot hurt.
|what‑it‑does||skin-identical ingredient | emollient|
|irritancy, com.||0, 1|
|irritancy, com.||0, 1|
|what‑it‑does||emulsifying | surfactant/cleansing|
|irritancy, com.||3, 2|
|what‑it‑does||soothing | moisturizer/humectant|
|irritancy, com.||0, 0|
|what‑it‑does||skin-identical ingredient | moisturizer/humectant|
|irritancy, com.||0, 0|
|what‑it‑does||antioxidant | soothing|
|what‑it‑does||soothing | emollient | moisturizer/humectant|
|what‑it‑does||antioxidant | soothing | perfuming|
|what‑it‑does||antioxidant | anti-acne|
|irritancy, com.||1-3, 1-3|
|irritancy, com.||0-3, 0-3|
|irritancy, com.||0, 0|
|what‑it‑does||skin-identical ingredient | moisturizer/humectant|
|irritancy, com.||0, 0|
|irritancy, com.||0, 1|
|what‑it‑does||moisturizer/humectant | emollient|
|what‑it‑does||chelating | viscosity controlling|
|irritancy, com.||0, 2|