AMADORIS

The Mask Breathe

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.

It also occurs naturally in our body and is used as a food additive. As cosmetic chemist Colins writes it, "its safety really is beyond any doubt".

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 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. 

Another pro is that lavender oil has some nice antimicrobial and antibacterial properties. It also has some local pain relieving and muscle relaxing magical powers. Lavender oil is also often claimed to have anti-inflammatory properties. We have found a study confirming this but it was the essential oil of the leaves and not the much more commonly used flowers and the two differ in their main chemical compounds very much. (The main components of the flower essential oil are linalyl acetate and linalool [around 80% the two together] while it is 1,8-Cineole [around 65%] in the essential oil of the leaves.)

Now, let us look at the cons: similar to a bunch of other essential oils, the main components of lavender oil are potentially irritating fragrant components. The two main components are linalyl acetate (about 50%) and linalool (about 35%) and both autoxidise on exposure to the air forming strong contact allergens. To make things even worse, lavender oil seems to be cytotoxic from concentrations as low as 0.25% (concentration up to 0.125% were ok). 

There is also an often cited Japanese study that made patch tests with lavender oil for 9 years and found a huge increase in lavender oil sensitivity in 1997 (from 1.1% in 1990 to 8.7% in 1997 and 13.9% in 1998). This was the year when using dried lavender flowers in pillows, wardrobes, and elsewhere became fashionable in Japan, so it seems that increased exposure to lavender results in increased risk of sensitivity.

Overall, it makes us sad to write bad things about such a lovely plant, but when it comes to skincare, you will be better off without lavender. 

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.

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 study made in the UK with 483 people tested the allergic reaction to 3% oxidised linalool and 2.3% had positive test results. 

Our intro did get pretty big after all (sorry for that), so let's get to the point finally: sunflower oil - similar to other plant oils - is a great emollient that makes the skin smooth and nice and helps to keep it hydrated. It also protects the surface of the skin and enhances the damaged or irritated skin barrier. Leslie Bauman notes in Cosmetic Dermatology that one application of sunflower oil significantly speeds up the recovery of the skin barrier within an hour and sustains the results 5 hours after using it.

It's also loaded with fatty acids (mostly linoleic (50-74%)  and oleic (14-35%)). The unrefined version (be sure to use that on your skin!) is especially high in linoleic acid that is great even for acne-prone skin. Its comedogen index is 0, meaning that it's pretty much an all skin-type oil. 

Truth be told, there are many great plant oils and sunflower oil is definitely one of them.

Soothing: the manufacturer tested out the soothing effect in vivo (meaning on humans that is always a good thing!) by measuring how 3% Biosaccharide Gum-1 decreased the tingling sensation caused by 10% lactic acid. The result was good: the tingling was decreased by 47%.

Moisturizing: Compared to famous hyaluronic acid, it turns out that the two are great together. HA has a quicker effect and provides more instant hydration (much more hydration was measured after 1h of application), while our nice sugar has a somewhat delayed effect demonstrating stronger hydration after 3h of application. After 8 hours both had similar moisturizing effect. 

Anti-aging: According to ex-vivo tests (meaning not on humans, so do not trust it too much) Biosaccharide Gum-1 can stimulate a protein in our skin called sirtuin-1. This is supposed to help our skin cells to live longer, and function better. 

Resurfacing:  The sirtuin-1 stimulation also results in quicker cell renewal - something that happens anyway but slows down as we age. And the quicker cell renewal is good because it helps the regeneration of the barrier function. That is especially nice for fragile, sensitive skin.

Touch: our fermented sugar is not only good to the skin, but it also feels great on the skin. It gives a nice “soft touch” feeling and makes the products pleasant to use. 

The bottom line is that the above info is from the manufacturer (and we could not find any relevant independent research) so obviously take it with a grain of salt. But Biosaccharide Gum-1 does look as an interesting and promising ingredient that’s why it earned our goodie rating. 

One of the biological activities of the centellosides is to be able to stimulate GAGs  (glycosaminoglycans - polysaccharides that are part of the liquidy stuff between our skin cells), and especially hyaluronic acid synthesis in our skin. This is probably one of the reasons why Centella Asiatica Extract has nice skin moisturizing properties that was confirmed by a 25 people, four weeks study along with Centella's anti-inflammatory effects.

Madecassoside can also help in burn wound healing through increasing antioxidant activity and enhancing collagen synthesis. Asiaticoside was shown to increase antioxidant levels on rats skin when applied at 0.2%. 

Centella Asiatica also often shows up in products that try to treat cellulite or striae. Of course, it cannot make a miracle but it might have some effect via regulating microcirculation and normalizing the metabolism in the cells of connective tissues. 

Bottom line: Gotu Kola is a great plant ingredient with proven wound healing, anti-inflammatory, and antioxidant properties. Nice to spot on any ingredient list.  

What's the problem?

Firstly, it's stability is only similar to that of pure ascorbic acid (AA), which means it is not really stable. A great study in the Journal of Cosmetic Dermatology compared a bunch of vitamin C derivatives and this derivative was the only one where the study said in terms of stability that it's "similar to AA". Not really that good.

Second, a study that examined the skin absorption of vitamin C found that ascorbyl palmitate did not increase the skin levels of AA. This does not mean that ascorbyl palmitate cannot penetrate the skin (because it can, it's oil soluble and the skin likes to absorb oil soluble things) but this means that it's questionable if ascorbyl palmitate can be converted into pure Vit C in the skin. Even if it can be converted, the palmitate part of the molecule is more than the half of it, so the efficacy will not be good and we have never seen a serum that contains a decent (and proudly disclosed) amount of AP.  We are highly skeptical what effect a tiny amount of AP has in a formula.

Third, another study that wanted to examine the antioxidant properties of AP was surprised to find that even though AP does have nice antioxidant properties; following UVB radiation (the same one that comes from the sun) it also promotes lipid peroxidation and cytotoxicity. It was only an in-vitro study meaning that it was done on cell cultures and not on real people, but still, this also does not support the use of AP too much. 

The only good thing we can write about Ascorbyl Palmitate is that there is an in-vitro (made in the lab, not on real people) study showing that it might be able to boost collagen production.

Regarding the skin-brightening properties of pure vitamin C, this is another magic property AP does not have, or at least there is no data, not even in-vitro, about it.

Overall, Ascorbyl Palmitate is our least favorite vitamin C derivative. It is there in lots of products in tiny amounts (honestly, we do not really understand why), however, we do not know about any vitamin C serum featuring AP in high amounts. That is probably no coincidence. If you are into vitamin C, you can take a look at more promising derivatives here. 

As for cosmetics, the CIR (Cosmetic Ingredient Review) concluded that the amount of BHT used in cosmetic products is low (usually around 0.01-0.1%),  it does not penetrate skin far enough to be absorbed into the bloodstream and it is safe to use in cosmetics.

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.