Renew Brightening Serum
Kri Skincare Renew Brightening 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.
We don't have description for this ingredient yet.
It's the flower water coming from the flowers of bitter orange (which is the sister of the sweet orange we all know and eat). In general, flower waters (also called hydrosols) are diluted versions of essential oils coming from the same plant. They contain the same components but in far less of a concentration.
So - similar to its essential oil big sister - orange flower water contains a lot of fragrant components and has a nice, sweet scent. It has some skin toning properties and can help to relax the body.
If your skin is super sensitive, it's a good idea to choose products without fragrant floral waters.
- 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
Also known as Sugarcane, Saccharum Officinarum is a handy moisturizing ingredient mostly used as a humectant. This means that it can help the skin to attract water and then to hold onto it.
It bears a close relationship to AHA superstar, Glycolic Acid that can be derived from it, so it's often claimed that Sugarcane Extract itself also exfoliates and brightens the skin. We could not find any research studies to back this up, but Saccharum Officinarum very often comes to the formula combined with other acid containing plant extracts trade named ACB Fruit Mix. According to manufacturer data, 5% of the fruit mix increases cellular renewal by 24%, while 4% pure Glycolic did the same by 33%. So maybe, a tiny bit of exfoliation, but if you want proven efficacy, stick to pure acids.
- It’s a polyhydroxy acid (PHA), that is often referred to as next generation AHA
- It gently lifts off dead skin cells form the skin surface making skin smooth and even
- In the long term it provides anti-aging benefits, like increased skin thickness and decreased wrinkles (though a tad less than even more proven superstar AHAs)
- It’s a great moisturizer and even helps to repair impaired skin barrier
- It’s antioxidant, and does not make your skin more sensitive to the sun
- It can be used even if your skin is very sensitive, rosacea prone or if you are post cosmetic procedure
We have to start by writing that there are about 900 citrus species in the world, and plenty of them are used to make different kinds of extracts used in cosmetics. This particular one, Citrus Aurantium Dulcis Fruit Extract is a very common ingredient, however, the species "Citrus Aurantium Dulcis" seem to exist only on ingredient lists and the real world calls this guy Citrus Sinensis or, you know, orange.
To complicate matters further, there are lots of varieties and lots of extraction methods, so it is a bit hard to know what you are getting with this one, but we will try our best to summarize the possibilities.
A very common scenario is that Citrus Aurantium Dulcis Fruit Extract is on the ingredient list for its mild, natural exfoliant properties. It contains mainly citric acid and some malic acid, AHA exfoliants known for their skin renewing properties. If that's the case, it is usually combined with other AHA containing fruits such as bilberry, sugar cane, lemon, and sugar maple in a super popular ingredient mix trade named ACB Fruit Mix.
But orange fruit is loaded with lots of other active compounds with a wide variety of possible effects. A well-known one is the antioxidant vitamin C, aka ascorbic acid, but the dosage will vary based on the extraction method, and it’s possible that some of the ascorbic acid content will degrade before extraction process even takes place. If you want vitamin C in your skincare, that is smart, but do not rely on orange fruit extract for it.
Flavonoids (hesperidin, naringin, luteolin, and ferulic acid) are also nice active compounds with possible antioxidant, anti-inflammatory, and vasoprotective effects. Some of them (namely hesperidin and luteolin) might even have skin brightening activity by inhibiting tyrosinase, the famous enzyme needed for melanin production.
The orange extract also contains carbohydrates, aka sugars (mostly glucose, fructose, and sucrose, but also some bigger polysaccharides such as pectin) giving the ingredient some moisturizing properties.
Some essential oil content is usually also present in citrus fruit extracts, which means a nice scent and antibacterial properties, but also some questionable compounds such as fragrance allergen limonene or phototoxic compound bergaptene. If the amount is big enough to worry about is questionable, probably not, however, the same question applies to all the nice beneficial compounds.
Overall, we think that the orange fruit extract is a very complex ingredient with lots of potentially good things in it, but we could not find proper in-vivo (made on real people) studies made with standardized extracts to validate what it really does or does not under real-world use cases.
If life gives the cosmetic industry lemon, it makes lemon fruit extract. As to why, we can write here extremely similar things to our shiny description of orange fruit extract. Being both of them citruses, they contain very similar active compounds with very similar (potential) effects on the skin.
Just like orange fruit, lemon fruit also contains citric acid so it is commonly used as a natural, mild exfoliating agent. If this is the case, it is usually combined with other AHA containing fruit extracts such as bilberry, sugar cane, orange, and sugar maple in a super popular ingredient mix trade named ACB Fruit Mix.
But, citrus fruits are chemically complex mixtures with a bunch of other active components such as vitamin C, flavonoids, phenolics, carbohydrates and essential oil (this latter one coming from the rind of the fruit, but still present in some amount in the fruit extract). These have the potential to give lemon extract antioxidant, antibacterial, anti-dandruff, venotonic and moisturizing properties, but the essential oil also brings some questionable compounds such as fragrance allergen limonene or phototoxic compound bergaptene. If your skin is sensitive, be careful with citrus extracts.
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).
The extract coming from the Sugar Maple tree, the one whose leaf is on the Canadian flag and gives us maple syrup.
The main reason it is used in skin care is that it contains natural AHA acids, namely Malic and Tartaric, and hence why it supposedly helps slough off dead skin cells in combination with other acid-containing fruit extracts as part of the trade name ACB Fruit Mix. The manufacturer claims that both malic and tartaric increase elasticity in the skin, but from our research, the only confirmed uses of these acids are as pH adjusters, especially in the tiny amounts they can be found in the Fruit Mix (less than 1%).
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.
|what‑it‑does||skin-identical ingredient | moisturizer/humectant|
|irritancy, com.||0, 0|
|what‑it‑does||exfoliant | chelating|
|what‑it‑does||skin-identical ingredient | moisturizer/humectant|
|irritancy, com.||0, 0|