Phytosteryl Macadamiate is the combination of phytosterol and fatty acids coming from Macadamia oil. It is a botanical version of cholesteryl esters found in skin surface lipids. It comes to the ingredient list as part of L22, a skin surface lipid mimetic whose main job is barrier repair and skin hydration. 

Jojoba Oil/Macadamia Seed Oil Esters is the major component of a skin surface lipid mimetic mixture trade named L22.  So what the heck is a skin surface lipid mimetic mixture? Let's start with skin surface lipids (SLSs): these are the oily substances that your skin produces (mainly the sebaceous glands, a smaller part comes from the epidermis) to keep the skin nice and moisturized. The main components are fatty acids (FAs), triglycerides, cholesterol, cholesteryl esters, wax esters, and squalene. This mixture has a super important role in keeping the skin barrier healthy. So Jojoba Oil/Macadamia Seed Oil Esters is a jojoba and macadamia oil-derived ingredient that contains fatty acids, triglycerides, and wax esters. It comes to the formula with Squalene,  Phytosteryl Macadamiate (botanical sourced version of cholesteryl ester) and Phytosterols (botanical version of cholesterol) in the ratios found in young, healthy adult skin.  So the main skill of L22 is barrier repair and skin hydration and the manufacturer did several double-blind, vehicle-controlled studies to show it really works. It compared 3% of L22 with 3% of olive oil or 3% of caprylic/capric triglyceride alone or combined with Ceramide 2 in a vehicle. 60 minutes after the application, barrier recovery was by far the best by the L22 + Ceramide 2 (0.1%) combination, followed by L22 alone, and then by Olive + Ceramide 2 and Olive alone. Skin hydration was measured 4 hours after application and again, the L22 + Ceramide 2 combination performed the best followed by L22 alone. Another study compared 3% L22 with 3% petrolatum (the gold standard occlusive agent). After 1 hour, they performed similarly both for barrier repair and skin hydration, but after 2 weeks of use and a 1 week regression period, L22 showed significantly better results. So the bottom line is: if barrier repair is something that you are interested in, the skin surface lipids of L22 can definitely be worth a try. Even better, if the formula also contains Ceramide 2. 

Ectoin is a surprisingly well-researched, multi-functional active that can do from pollution & light protection to skin hydration, soothing, and barrier repair, several things to your skin. It is an extremolyte, a small stress-protection molecule that protects microorganisms living under extreme conditions such as salt lakes, hot springs, arctic ice, the deep sea, or deserts. It was discovered in 1985 in a microorganism living in a salt lake in the Egyptian desert. 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. 

Isosorbide Dicaprylate (IDC) is a smart, oil-loving skin hydrator and barrier builder molecule. It works synergistically with glycerin as it up-regulates Aquaporin 3 (AQP3), an important transmembrane protein that transports our beloved friend glycerin, along with its’ hydrating groupie water molecules that surround it, into the cell. To put it more simply - AQP3 makes sure that glycerin and water are well distributed in the outer layer of the skin and thus the skin is well-hydrated. IDC is also claimed to upregulate the expression of CD44 (a hyaluronic acid binding receptor), ceramide synthase (an enzyme required for ceramide synthesis), and decrease transepidermal water loss (TEWL).The clinical study done by the manufacturer showed that a direct comparison between 2% IDC versus 2% glycerin lotions revealed a three-fold advantage of IDC in giving skin hydration. Severely dry skin treated with 2% IDC + 2% glycerin showed 133% improvement, whereas 35% improvement was observed with moderately dry skin.

A nice-feeling, light emollient that makes the skin soft and smooth. It gives a fresh and gliding sensation with a powdery or soft after-feel depending on the exact grade used. It is a popular alternative to replace silicones. Chemically speaking, it is an alkane (stable, non-reacting hydrocarbon) that used to be produced from petrochemicals, but today's versions are vegetable based & readily biodegradable. 

An emollient liquid that usually comes to the formula combined with C12-15 Alkyl Benzoate and Dipropylene Glycol Dibenzoate as the trio works in synergy to solubilize hard to dissolve sunscreen agents while providing a nice, non-greasy skin feel. 

Acrylates/C12-22 Alkyl Methacrylate Copolymer is a big molecule created from repeating subunits (aka polymer) used as a film-former. It is great at improving the water and wear resistance of sunscreens and makeup products.

An oily liquid that makes your skin nice and smooth (aka emollient). It is also claimed to have some humectant and moisturizing properties without a greasy after-feel. But its real superpower is being an outstanding solvent for hard to solubilize sunscreen agents (that is most of the chemical sunscreen filters) making it an excellent emollient choice in high SPF products. 

The salt form of the water-soluble chemical sunscreen, Ensulizole. What we wrote there (UVB filter with a peak protection at 306 nm), applies here as well. In fact, the pure acid form (aka Phenylbenzimidazole Sulfonic Acid) can be incorporated into a sunscreen formula only if it is neutralized with a base (otherwise it is not water-soluble), so even if the acid form in on the ingredient list, what you have in the formula is a salt form, just like this one.  You can read more here >> 

A silicone-based, chemical sunscreen agent that protects the skin in the UVB range (290-320 nm) with a peak absorbance at 312 nm. It is a colorless to pale yellow liquid with nice and non-shiny (at least compared to most other sunscreens) sensorial properties.  It is a pretty good team player and can stabilize the famously unstable UVA filter, avobenzone and works especially well with Ensulizole to achieve high SPF protection. It is approved up to 10% as a sunscreen filter in the EU and most parts of the world, except for the United States. 

Ethylhexyl Dimethyl PABA is a chemical sunscreen agent that protects in the UVB range (290-320 nm) with a peak absorbance at 312nm. Other than that, we struggle to write anything positive about this guy, as it is photo unstable (looses 10% efficacy in 20 mins and 50% in 85 mins), not an unfrequent allergen in sunscreens and shows some endocrine effect in animal studies.  All this does not mean that it is not considered safe as used, it is (and is approved up to 8% in the EU and US and up to 3% in Japan), but we do think that there are plenty of other and better UV filters out there. 

This long-named molecule is a chemical sunscreen agent that protects the skin from the UVA II rays (320-350 nm mainly) with a peak absorbance at 335 nm. Unlike most other sunscreen filters, it is not oil, but water-soluble helping formulators to create less greasy sunscreens. It also has a good safety profile with very low skin penetration and is approved up to 10% in the EU and pretty much everywhere else except for the United States (due to old and bad FDA sunscreen regulations). 

4-Methylbenzylidene Camphor is a chemical sunscreen agent that protects in the UVB range (290-320 nm) with a peak absorbance at 301 nm. It is an oil-soluble powder that is slightly photo-unstable (it takes 65 minutes to lose 10% of its protecting power and 345 minutes to lose half of it), but it can still help to stabilize the famously unstable UVA filter, avobenzone.  Regarding its safety, we do not have the best news. Two possible concerns are that it absorbs into the body and might have some estrogenic activity there. But do not panic, the latter one was only shown in rats and is probably not the case in humans, and  4-Methylbenzylidene Camphor is considered safe as used. It is legally approved both in the EU and  Australia up to 4%, however, it is not approved in the US and in Japan.  Overall, we think there are better UVB filter choices out there than this guy, but if your favorite sunscreen contains it, you should probably just continue to use it. 

Benzophenone-5 is the sodium salt brother of Benzophenone-4, and just like that guy, this one also works mainly as a photoprotectant to extend product shelf life, or as a color-protectant for products in clear packages.