BioAqua

Oat Rejuvenating & Moisturizing Facial Mask

Ok, so now we know what ceramides are, let's see what they do in our skin: research shows clearly that they play a super important role in keeping the skin barrier healthy and the skin hydrated. If ceramides in the skin are decreased, more water can evaporate from the skin and there is less water remaining in the skin. So ceramides form kind of a "water-proof" protecting layer and make sure that our skin remains nice and hydrated. 

Now the question is only this: If we put ceramides all over our face do they work as well as ceramides already naturally in our skin? Well, the answer is probably a no, but they do work to some extent. The BeautyBrains blog made a fantastic article about ceramides and they have listed a couple of examples about studies showing that ceramides - especially when used in certain ratios with cholesterol and fatty acids  - do hydrate the skin and can help to repair the skin barrier.

So far we were writing about ceramides in plural. It's because there are lots of different ceramides, a 2014 article writes that currently 12 base classes of ceramides are known with over 340 specific species. Chemically speaking, ceramides are the connection of a fatty acid and a sphingoid base and both parts can have different variations that result in the different types of ceramides. 

Our current one, Ceramide 1, or more recently called Ceramide EOP, was the first one that was identified in 1982 and it's a special snowflake. It contains the essential fatty acid, linoleic acid and has a unique structure. It's believed that ceramide 1 plays a "binding role" in the lipid layers of the extracellular matrix. Along with ceramides 4 and 7, they also play a vital role in epidermal integrity and serve as the main storage areas for linoleic acid (a fatty acid that's also very important for barrier repair).  

Oh, and one more thing: alkaline pH inhibits enzymes that help ceramide synthesis in our skin. So if you use a soap and you notice your skin is becoming dry, now you know why. 

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.

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!). 

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 complication, however, is that different extracts and distillates can be made from different parts of the plant (bark, twigs, and leaves are typically used) and different extraction methods from different parts produce different results. So if you see only Witch Hazel Extract or Witch Hazel Water on the ingredient list, it's a bit hard to know what you're actually getting but we will try to summarize the possibilities to give an idea.

The main biologically active components in Witch Hazel are hamamelitannin (a potent astringent and antioxidant), catechins (anti-inflammatory and antioxidant) and gallic acid (antibacterial). The bark extract contains by far the most hamamelitannin and it has the most gallic acid and catechins. The twigs contain fewer catechins, less gallic acid, and much less hamamelitannin (4.77% vs 0.18%). The leaves contain hardly any tannins (0.04%) or catechins and contain a medium amount of gallic acid (compared to the bark and twigs).

Witch Hazel also contains tiny amounts of the essential oil and fragrance component eugenol, but the amount is so small that it's probably not significant for the skin.

Apart from the differences in active components in different parts of the Witch Hazel bush, the extraction methods also vary. Witch Hazel Distillate contains 14% added alcohol according to the USP specifications  and alcohol is, at best drying, and at worst skin-damaging. Luckily, there are also alcohol-free distillates, so if you prefer no alcohol check the ingredient list carefully. Witch Hazel Extracts can also be made in different ways: browsing Ulprospector, we could find hydroglycolic, hydroalcoholic and glicerine/water based extracts.

Well-known skin care expert, Paula Begoun rates witch hazel as poor and says,  "depending on the form of witch hazel, you’re exposing your skin either to a sensitizing amount of alcohol or to tannins, or both." This might be the case if you are dealing with an alcoholic witch hazel bark water or extract, but looking at CosIng (the official INCI name listing of the EU), witch hazel bark water or witch hazel bark extract are not listed ingredients. Bark and leaf or bark and twig or all three are used together to create extracts, so the chance that there is too much hamamelitannin in the final cosmetic ingredient seems small. Also alcohol-free extracts and distillates exist; actually, the majority seem to be alcohol-free nowadays. So all in all, we think "Hamamelis Virginiana Extract" on the ingredient list is nothing to worry about.

We even found a German study that compared the efficacy of Hamamelis ointment to panthenol ointment for soothing the skin in children (from 27 days to 11 years old). They observed 309 children and concluded that both ointments were similarly effective but the one with Hamamelis was even better tolerated (98.2% vs. 92.3% tolerated well the ointments in the two groups).

All in all, Witch Hazel Extract is a sloppy INCI name (btw, not in the CosIng listing), and you do not really know what you're getting. Most probably though, you are getting a goody with nice astringent, soothing, antibacterial, and even antioxidant properties.

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. 

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.