Kireyna

Eiyō – Nourishing And Balancing Serum

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).

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. 

The key skill of Ectoin is protection that applies also to the skin. Its main mode of action is binding water molecules (aka kosmotropic) and creating hydro complexes. These complexes then surround important biomolecules (e.g. cells, proteins, enzymes) and form a stabilizing hydration shell around them. 

This protection mechanism means good things when it comes to our skin: Ectoin has antioxidant, anti-inflammatory, pollution& light protecting, skin hydrating, barrier repairing as well as anti-aging properties. 

A placebo-controlled 10-person study examined a four-week treatment with 0.5% Ectoin in the crow's feet area and found a significant anti-wrinkle effect (-19% mean wrinkle depth) in 100% of the participants. Another double-blind, placebo-controlled clinical study with 24 participants used a 2% Ectoin cream twice a day for 4 weeks and found an improvement in all of the measured parameters, such as wrinkle volume, skin scaling, roughness, and elasticity. 

Another remarkable property of Ectoin is protecting the epidermal immune cells called Langerhans cells from UV damage. 0.3% and 0.5% Ectoin cream was used twice a day for 14 days on the forearm and then irradiated with 1.5 MED UV (one and a half times the UV dose that causes detectable redness). While the untreated, UV-stressed area showed a 40% decrease in viable Langerhans cells, 0.5% Ectoin showed 100% protection (and 0.3% showed ~95% protection). 

The soothing efficacy is also backed up by multiple in-vivo studies. A 20-person study compared 1% Ectoin cream to 0.25% hydrocortisone treatment on surfactant irritated skin and found similar effectiveness in reducing skin redness.  Another study with 23 females with sensitive skin found that a 1% Ectoin cream helped to tolerate a 0.5% or 1% retinol treatment much better.  

A tiny, 5-person study examined the long-term (7 days) skin hydration effect of 1% Ectoin. During the study, hydration levels increased up to 200% compared to placebo, and even 7 days after stopping the treatment hydration status was largely preserved. Higher concentration (5-7%) Ectoin treatments are also used as OTC medical products for the treatment of eczema or atopic skin. 

The anti-pollution magic properties are also well-established and Ectoin is currently the only anti-pollution active ingredient approved for use in medical products (e.g. inhalation solutions) in Europe. Clinical studies showed a reduction of inflammations in human lungs of patients with COPD (a pulmonary disease) and pollution-induced asthma. But coming back to the skin, Ectoin protects both from PMs (Particulate Matters, including ultrafine) as well as PAHs (Polycyclic Aromatic Hydrocarbons) and heavy metals. 

If that weren't enough, Ectoin is also shown to protect the skin from blue and visible light, and pigmentation resulting from environmental stress (think UV, pollution, oxidative stress). 

All in all, we think Ectoin is one of those under-the-radar actives that deserves more hype than it is currently getting. As an amazing all-around skin protectant, it is a useful addition to any skincare routine. 

On the downside, the biological role of LMW-HA in the skin is being a pro-inflammatory signaling agent and there is a study by another manufacturer called Evonik showing that HA versions with smaller than 50kDa molecular weight might be pro-inflammatory when put on the skin. Granted, the study was only done on reconstituted human epidermis, so it might or might not be like this on real human skin. 

If you wanna get confused and read much more about hyaluronic acid and what the different molecular weight versions might or might not do, click here and read our excruciatingly long description. 

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.