Tropic

Eye Work

Second, still according to Estee Lauder research but now from 2012 the ingredient has anti-microbial and anti-inflammatory properties and holds promise in the treatment of acne and rosacea. For the former one 5% was needed to show effectiveness, but for reducing skin sensitivity already 1% showed results. 

The anti-acne effect is confirmed also by US manufacturer, Barnet, that says that Lactobacillus ferment is helpful in killing harmful bacteria and creating a healthy balanced microflora. Compared to well-known anti-acne and anti-inflammatory salicylic acid the probiotic worked faster at reducing the size and redness of acne lesions. 

It also goes by the trade name Leucidal Liquid SF and can serve in the formula as a natural preservative. 

Bottom line: It’s not the most proven ingredient (yet) but definitely a very promising one especially if you have sensitive skin, acne or rosacea.  

A well-known thing about Caffeine is that it improves the microcirculation of the blood vessels. Though conventional wisdom and anecdotal evidence says that this property is helpful for dark under-eye circles and puffy eyes, we have to mention that the double-blind research we have found about a 3% caffeine gel concluded that "the overall efficacy of the selected caffeine gel in reducing puffy eyes was not significantly different from that of its gel base."  But you know, the proof is in the pudding.

Another thing Caffeine is used for in body care products is its anti-cellulite effects. In theory, it can speed up the lipolysis process (the "fat burning"  by our cells) and stimulate the draining lymph system that might lead to the improvement of cellulite. But here again, the evidence that it actually makes a measurable, let alone visible,  improvement on actual human beings is limited (we could find only some animal skin studies or caffeine being combined with other actives). 

Last, but not least, we have to write about caffeine and hair growth. The theory is that it can inhibit the activity of the 5-α-reductase enzyme that plays an important role in hair loss and allows a renewed growth phase of the hair. We have found some recent and promising research to back this up. A 2017 study compared a 0.2% caffeine liquid with a 5% Minoxidil  (an FDA approved active to treat baldness) solution and found that  "a caffeine-based topical liquid should be considered as not inferior to minoxidil 5% solution in men with androgenetic alopecia", or English translation means that the caffeine liquid was pretty much as good as the FDA-approved Minoxidil stuff. Not bad!

Overall, we think that caffeine is a very versatile and biologically active ingredient. Even though some of its effects are more hyped up than backed up, it is still a nice to have on many ingredient lists. 

It also occurs naturally in our body and is used as a food additive. As cosmetic chemist Colins writes it, "its safety really is beyond any doubt".

It also helps to deliver water-soluble actives such as caffeine more effectively, and can even boost SPF in sunscreen formulas. Its typical use level is 1-5% and has wide compatibility with other actives and oils.

Overall, a real multi-tasker with nice sensorial properties. No wonder it is so popular.

Second, the same amount can also fade - always stubborn - brown spots. (Do not expect magic, though - the photos from the study show the difference after 8 weeks of daily use. The difference is visible, but not that big. It's always good to have realistic expectations. :))  Combined with skincare superstar niacinamide the duo is synergistic and is more effective at improving hyperpigmentation, so if you are after the skin-lightening benefit look out for products that contain both. 

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.

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. 

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).

What's the problem?

Firstly, it's stability is only similar to that of pure ascorbic acid (AA), which means it is not really stable. A great study in the Journal of Cosmetic Dermatology compared a bunch of vitamin C derivatives and this derivative was the only one where the study said in terms of stability that it's "similar to AA". Not really that good.

Second, a study that examined the skin absorption of vitamin C found that ascorbyl palmitate did not increase the skin levels of AA. This does not mean that ascorbyl palmitate cannot penetrate the skin (because it can, it's oil soluble and the skin likes to absorb oil soluble things) but this means that it's questionable if ascorbyl palmitate can be converted into pure Vit C in the skin. Even if it can be converted, the palmitate part of the molecule is more than the half of it, so the efficacy will not be good and we have never seen a serum that contains a decent (and proudly disclosed) amount of AP.  We are highly skeptical what effect a tiny amount of AP has in a formula.

Third, another study that wanted to examine the antioxidant properties of AP was surprised to find that even though AP does have nice antioxidant properties; following UVB radiation (the same one that comes from the sun) it also promotes lipid peroxidation and cytotoxicity. It was only an in-vitro study meaning that it was done on cell cultures and not on real people, but still, this also does not support the use of AP too much. 

The only good thing we can write about Ascorbyl Palmitate is that there is an in-vitro (made in the lab, not on real people) study showing that it might be able to boost collagen production.

Regarding the skin-brightening properties of pure vitamin C, this is another magic property AP does not have, or at least there is no data, not even in-vitro, about it.

Overall, Ascorbyl Palmitate is our least favorite vitamin C derivative. It is there in lots of products in tiny amounts (honestly, we do not really understand why), however, we do not know about any vitamin C serum featuring AP in high amounts. That is probably no coincidence. If you are into vitamin C, you can take a look at more promising derivatives here. 

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.