Ever White

Let It Glow Strawberry Clay Mask

No matter the color, bentonite is excellent at absorbing things: it can suck up the sebum and gunk from the skin and make it instantly smooth and matte. Not only that, but bentonite has a negative ionic charge and thus can attract things with a positive charge. Things with a positive charge include bad bacteria and toxins and bentonite clay masks can help to clear those out of the skin and pores (btw, bentonite is edible and has the same detoxifying effect internally). 

Thanks to bentonite's effect against bad bacteria and pathogens, there is also some research showing that bentonite can help to calm skin infections, soothe skin allergies and might work for skin conditions like psoriasis and eczema.

On the other hand, the downside of bentonite being such a good absorbent is that it can suck up more than the excess sebum and used too often, it can easily dry out the skin. So use it for good measure, and never forget to moisturize afterwards.

A 2015 research paper on the potential of uses of algae in cosmetics summarizes that algae are rich sources of biologically active metabolites including antioxidants, anti-inflammatory agents, alginates, polysaccharides, and carotenoids. Currently, algae extracts are mostly used as moisturizing and thickening agents, but algae also have great potential to combat skin aging, pigmentation as well as working as an antimicrobial.

We have also browsed through Prospector to see what manufacturers say about their algae. There is, for example, an algae extract trade-named Lanablue that comes from blue-green algae (green algae is rare, less than 1% of the total macroalgae in the world) and is claimed to have retinoid like effects (i.e. reduce wrinkles, smooth skin) but without the side effects (though it seems now that the INCI name of Lanablue was changed to Aphanizomenon Flos-Aquae Extract). 

There is another algae extract from another manufacturer that comes from red algae (much more common, about 40% of total macroalgae worldwide) and is claimed to have not only moisturizing but also skin smoothing and densifying effects. 

Here is a brown algae extract (the most common type, about 59% of macroalgae), also just called Algae Extract on the product label that is simply claimed to be a free radical scavenger, aka antioxidant. These were just three random examples from three manufacturers all called Algae extract even though they all come from different algae with different claims.

Anyhow, the point is this; there are tons of different types of Algae Extracts out there. Unless the brand tells you what they use, it's impossible to know for sure. The most probable scenario for the Alge Extract is that it works as a moisturizer and emollient and it might have some additional anti-aging properties.

If you are into chemistry (if not, we understand, just skip this paragraph), the reason is that electrolytes (you know, the Na+ and Cl- ions) screen the electrostatic repulsion between the head groups of ionic surfactants and thus support the formation of long shaped micelles (instead of spherical ones) that entangle like spaghetti, and viola, a gel is formed. However, too much of it causes the phenomenon called "salting out", and the surfactant solution goes runny again. 

Other than that, salt also works as an emulsion stabilizer in water-in-oil emulsions, that is when water droplets are dispersed in the outer oil (or silicone) phase. And last but not least, when salt is right at the first spot of the ingredient list (and is not dissolved), the product is usually a body scrub where salt is the physical exfoliating agent. 

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. 

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.