Bioderma

Photoderm Mineral Compact Light SPF50+

Anyway, it doesn't matter if it reflects or absorbs, Titanium Dioxide is a pretty awesome sunscreen agent for two main reasons: it gives a nice broad spectrum coverage and it's highly stable. Its protection is very good between 290 - 350 nm (UVB and UVA II range), and less good at 350-400 nm (UVA I) range. Regular sized Titanium Dioxide also has a great safety profile, it's non-irritating and is pretty much free from any health concerns (like estrogenic effect worries with some chemical filters).

The disadvantage of Titanium Dioxide is that it's not cosmetically elegant, meaning it's a white, "unspreadable" mess. Sunscreens containing Titanium Dioxide are often hard to spread on the skin and they leave a disturbing whitish tint. The cosmetic industry is, of course, really trying to solve this problem and the best solution so far is using nanoparticles. The itsy-bitsy Nano-sized particles improve both spreadability and reduce the whitish tint a lot, but unfortunately, it also introduces new health concerns. 

The main concern with nanoparticles is that they are so tiny that they are absorbed into the skin more than we want them (ideally sunscreen should remain on the surface of the skin). Once absorbed they might form unwanted complexes with proteins and they might promote the formation of evil free radicals. But do not panic, these are concerns under investigation. A 2009 review article about the safety of nanoparticles summarizes this, "to date, in-vivo and in-vitro studies have not demonstrated percutaneous penetration of nanosized particles in titanium dioxide and zinc oxide sunscreens". The English translation is, so far it looks like sunscreens with nanoparticles do stay on the surface of the skin where they should be.  

All in all, Titanium Dioxide is a famous sunscreen agent and for good reason, it gives broad spectrum UV protection (best at UVB and UVA II), it's highly stable, and it has a good safety profile. It's definitely one of the best UV-filter agents we have today, especially in the US where new-generation Tinosorb filters are not (yet) approved. 

The first main difference is that while TiO2 gives a nice broad spectrum protection, Zinc Oxide has an even nicer and even broader spectrum protection. It protects against UVB, UVA II, and UVA I almost uniformly, and is considered to be the broadest range sunscreen available today. 

It's also highly stable and non-irritating. So much so that Zinc Oxide also counts as a skin protectant and anti-irritant. It's also often used to treat skin irritations such as diaper rash.

As for the disadvantages, Zinc Oxide is also not cosmetically elegant. It leaves a disturbing whitish tint on the skin, although, according to a 2000 research paper by Dr. Pinnell, it's slightly less white than TiO2. Still, it's white and disturbing enough to use Zinc Oxide nanoparticles more and more often. 

We wrote more about nanoparticles and the concerns around them here, but the gist is that if nanoparticles were absorbed into the skin that would be a reason for legitimate health concerns. But luckily, so far research shows that sunscreen nanoparticles are not absorbed but remain on the surface of the skin or in the uppermost (dead) layer of the skin. This seems to be true even if the skin is damaged, for example, sunburnt. 

All in all, if you've found a Zinc Oxide sunscreen that you are happy to use every single day, that's fantastic and we suggest you stick with it. It's definitely one of the best, or probably even the best option out there for sun protection available worldwide. 

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.