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SeneGence Seneserum C

Seneserum C

SeneSerum-C features one of the most well-known anti-aging ingredients, Vitamin C. This hydrating formula is great for all skin types and works to protect the skin, resulting in a brighter, firmer-looking, more youthful appearance. It is light and can be used during the day or at night under moisturizers.
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Ingredient name what-it-does irr., com. ID-Rating
Aqua/Water/Eau solvent
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
Propanediol solvent, moisturizer/​humectant
Tetrahexyldecyl Ascorbate antioxidant, skin brightening goodie
Spirulina Maxima (Algae) Extract
Saccharomyces Cerevisiae (Yeast) Extract moisturizer/​humectant goodie
Arnica Montana (Arnica) Flower Extract perfuming icky
Camellia Sinensis (Green Tea) Leaf Extract antioxidant, soothing superstar
Vitis Vinifera (Grape) Juice Extract exfoliant, antioxidant goodie
Faex (Yeast) Extract/Extrait De Levure moisturizer/​humectant goodie
Orchis Mascula (Orchid) Flower Extract soothing
Simmondsia Chinensis (Jojoba) Seed Extract abrasive/​scrub, emollient
Vaccinium Angustifolium (Blueberry) Fruit Extract soothing
Vaccinium Macrocarpon (Cranberry) Fruit Extract
Lycium Chinense (Chinese Wolfberry) Fruit Extract antioxidant
Arabidopsis Thaliana (Thale-Cress) Extract antioxidant
Retinyl Palmitate cell-communicating ingredient 1-3, 1-3
Tocopheryl Acetate antioxidant 0, 0
Sodium Hyaluronate skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Hydroxyethylcellulose viscosity controlling
Calcium Alginate viscosity controlling
Xanthan Gum viscosity controlling
Ethylhexylglycerin preservative
Gellan Gum viscosity controlling
Biosaccharide Gum-4
Citric Acid buffering
Biosaccharide Gum-1 soothing, moisturizer/​humectant goodie
Sorbic Acid preservative
Copper Pca moisturizer/​humectant
Magnesium Pca moisturizer/​humectant
Zinc Pca anti-acne, moisturizer/​humectant goodie
Carrageenan viscosity controlling
Lecithin emollient, emulsifying goodie
Potassium Sorbate preservative
Sea Salt
Ergothioneine antioxidant
Phenoxyethanol preservative
Parfum/Fragrance perfuming icky
Linalool perfuming icky
Geraniol perfuming icky
Citronellol perfuming icky
Hexyl Cinnamal perfuming icky
Butylphenyl Methylpropional perfuming icky
Alpha-Isomethyl Ionone perfuming icky
Coumarin perfuming icky
Limonene perfuming, solvent icky
Eugenol perfuming icky
Mica colorant
Titanium Dioxide (Ci 77891) colorant 0, 0

SeneGence Seneserum C
Ingredients explained

Also-called: Aqua;Water | What-it-does: solvent

Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product. 

It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water. 

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. 

Glycerin - superstar
Also-called: Glycerol | What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0
  • A natural moisturizer that’s also in our skin
  • A super common, safe, effective and cheap molecule used for more than 50 years
  • Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
  • Effective from as low as 3% with even more benefits at higher concentrations up to 20-40% (around 10% is a good usability-effectiveness sweet spot)
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

Also-called: Zemea | What-it-does: solvent, moisturizer/humectant

Propanediol is a natural alternative for the often used and often bad-mouthed propylene glycol. It's produced sustainably from corn sugar and it's Ecocert approved. 

It's quite a multi-tasker: can be used to improve skin moisturization, as a solvent, to boost preservative efficacy or to influence the sensory properties of the end formula. 

Also-called: Form of Vitamin C, Ascorbyl Isotetrapalmitate, Ascorbyl Tetraisopalmitate, ATIP | What-it-does: antioxidant, skin brightening

Tetrahexyldecyl Ascorbate is a stable, oil-soluble form of skincare big shot Vitamin C. If you do not know, why Vitamin C is such a big deal in skincare, click here and read all about it. We are massive vitamin C fans and have written about it in excruciating detail.

So now, you know that Vitamin C is great and all, but it's really unstable and gives cosmetics companies many headaches. To solve this problem they came up with vitamin C derivatives, and one of them is Tetrahexyldecyl Ascorbate (let's call it ATIP in short).

It's a really promising candidate (see below), but while reading all the goodness about it in a minute, do not forget that derivatives not only have to be absorbed into the skin but also have to be converted to pure vitamin C (ascorbic acid or AA) and the efficacy of the conversion is often unknown. In addition, vitamin C's three magic properties (antioxidant, collagen booster, skin brightener) are all properly proven in-vivo (on real people), but for the derivatives, it's mostly in-vitro studies or in the case of ATIP, it's in-vitro and done by an ingredient supplier.

With this context in mind let's see what ATIP might be able to do. First, it is stable (if pH < 5), easy to formulate and a joy to work with for a cosmetic chemist.

Second, because it's oil-soluble, its skin penetration abilities seem to be great. So great in fact, that it surpasses the penetration of pure vitamin C threefold at the same concentration and it penetrates successfully into the deeper layers of the skin (that is usually important to do some anti-aging work). There is also in-vitro data showing that it converts to AA in the skin. 

Third, ATIP seems to have all three magic abilities of pure vitamin C: it gives antioxidant protection from both UVB and UVA rays, it increases collagen synthesis (even more than AA) and it has a skin brightening effect by reducing melanogenesis by more than 80% in human melanoma cell cultures.

So this all sounds really great, but these are only in-vitro results at this point. We could find Tetrahexyldecyl Ascorbate mentioned only in one published in-vivo study that examined the anti-aging properties of a silicone formula containing 10% AA and 7% ATIP. The authors theorized that the 10% AA is released slowly from the silicon delivery system and probably stays in the upper layer of the skin to give antioxidant benefits, while ATIP penetrates more rapidly and deeply and gives some wrinkle-reducing benefits. The study was a small (10 patients), double-blind experiment, and the formula did show some measurable anti-aging results. However, it is hard to know how much pure vitamin C or ATIP can be thanked.

Bottom line: a really promising, but not well-proven vitamin C derivative that can be worth a try especially if you like experimenting (but if you like the tried and true, pure vitamin C will be your best bet).

We don't have description for this ingredient yet.

Also-called: Baker's Yeast | What-it-does: moisturizer/humectant

Saccharomyces cerevisiae (SC)  is the fancy name for common baker’s yeast. 

Usually different kind of yeast extracts are used in skincare for their great hydrating, and general skin conditioning properties. We could find one research paper to back this up: It has found that SC indeed increases skin moisture and had improved skin microrelief (the small wrinkles and surface irregularities of skin). 

According to manufacturer info coupled with the Mexican cactus, prickly pear it also helps to reduce neurosensory irritation that might occur from potent retinol or AHA products. 

Also-called: Mountain Arnica Extract | What-it-does: perfuming

A nice yellow flower living in the mountains. It has been used as a herbal medicine for centuries, though its effect on skin is rather questionable. It's most famously used to treat bruisings, but there are some studies that show that it's not better than placebo (source: wikipedia).  Also, some consider it to be anti-inflammatory, while other research shows that it can cause skin irritation. 

Also-called: Green Tea | What-it-does: antioxidant, soothing
  • Green tea is one of the most researched natural ingredients
  • The active parts are called polyphenols, or more precisely catechins (EGCG being the most abundant and most active catechin)
  • There can be huge quality differences between green tea extracts. The good ones contain 50-90% catechins (and often make the product brown and give it a distinctive smell)
  • Green tea is proven to be a great antioxidant, UV protectant, anti-inflammatory, anticarcinogenic and antimicrobial
  • Because of these awesome properties green tea is a great choice for anti-aging and also for skin diseases including rosacea, acne and atopic dermatitis
Read all the geeky details about Camellia Sinensis Leaf Extract here >>

Also-called: Grape Juice Extract | What-it-does: exfoliant, antioxidant

It's a liquid extract coming from grape. According to manufacturer info, it's a skin peeling agent, aka exfoliant, that contains a nice mix of AHA acids (if those magic three letters do not tell you anything, you must click here now.) 

About 40% of the extract is a mix of tartaric, malic, lactic, citric and gluconic acid and they work to gently lift off dead skin cells to reveal nicer fresher skin underneath. The manufacturer also claims that the exfoliation with grape juice extract is very well tolerated and depending on the concentration the result can be soft or even strong exfoliation.

What-it-does: moisturizer/humectant

You probably know yeast from the kitchen where you put it into milk with a little sugar and then after a couple of minutes brownish bubbles form. That is the fungi fermenting the sugar

As for skin care, yeast contains beta-glucan that is a great soothing ingredient and also a mild antioxidant.  The yeast extract itself is a silky clear liquid that has some great moisturizing, skin protecting and film-forming properties on the skin. 

What-it-does: soothing

We don't have description for this ingredient yet.

What-it-does: abrasive/scrub, emollient

We don't have description for this ingredient yet.

Also-called: Blueberry Extract | What-it-does: soothing

We don't have description for this ingredient yet.

Also-called: Cranberry Fruit Extract | What-it-does: astringent

We don't have description for this ingredient yet.

What-it-does: antioxidant

We don't have description for this ingredient yet.

What-it-does: antioxidant

We don't have description for this ingredient yet.

Also-called: Form of Retinoids | What-it-does: cell-communicating ingredient | Irritancy: 1-3 | Comedogenicity: 1-3

It's an ester form of vitamin A (retinol + palmitic acid) that belongs to the "retinoid family". The retinoid family is pretty much the royal family of skincare, with the queen being the FDA-approved anti-aging ingredient tretinoin. Retinol is also a very famous member of the family, but it's like Prince William, two steps away from the throne. Retinyl palmitate will be then little Prince George, quite far (3 steps) away from the throne. 

By steps, we mean metabolic steps. Tretinoin, aka retinoic acid, is the active ingredient our skin cells can understand and retinyl palmitate (RP) has to be converted by our metabolic machinery to actually do something. The conversion is a 3 step one and looks like this:

retinyl palmitate --> retinol -- > retinaldehyde --> all-trans-retinoic acid

As we wrote in our lengthy retinol description the problem is that the conversion is not terribly effective. The evidence that RP is still an effective anti-aging ingredient is not very strong, in fact, it's weak. Dr. Leslie Baumann in her fantastic Cosmetic Dermatology book writes that RP is topically ineffective

What's more, the anti-aging effectiveness is not the only questionable thing about RP. It also exibits questionable behaviour in the presence of UV light and was the center of a debate between the non-profit group, EWG (whose intentions are no doubt good, but its credibility is often questioned by scientists) and a group of scientists and dermatologists lead by Steven Q. Wang, MD,  director of dermatologic surgery at Memorial-Sloan Kettering Cancer Centre. 

Dr. Leslie Baumann wrote a great review of the debate and summarized the research available about retinyl palmitate here.  It seems that there is a study showing RP being photo protective against UVB rays but there is also a study showing RP causing DNA damage and cytotoxicity in association with UVA. 

We think that the truth lies somewhere in the middle, and we agree with Dr. Baumann's conclusion: "sufficient evidence to establish a causal link between RP and skin cancer has not been produced. Nor, I’m afraid, are there any good reasons to recommend the use of RP". We would add especially during the day!

Bottom line: If you wanna get serious about retinoids, RP is not your ingredient (retinol or tretinoin is!). However, if you use a product that you like and it also contains RP, there is no reason to throw it away. If possible use it at night, just to be on the safe side.

Also-called: Vitamin E Acetate | What-it-does: antioxidant | Irritancy: 0 | Comedogenicity: 0

It’s the most commonly used version of pure vitamin E in cosmetics. You can read all about the pure form here. This one is the so-called esterified version. 

According to famous dermatologist, Leslie Baumann while tocopheryl acetate is more stable and has a longer shelf life, it’s also more poorly absorbed by the skin and may not have the same awesome photoprotective effects as pure Vit E. 

What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

It’s the - sodium form - cousin of the famous NMFhyaluronic acid (HA). If HA does not tell you anything we have a super detailed, geeky explanation about it here.  The TL; DR version of HA is that it's a huge polymer (big molecule from repeated subunits) found in the skin that acts as a sponge helping the skin to hold onto water, being plump and elastic. HA is famous for its crazy water holding capacity as it can bind up to 1000 times its own weight in water.

As far as skincare goes, sodium hyaluronate and hyaluronic acid are pretty much the same and the two names are used interchangeably. As cosmetic chemist kindofstephen writes on reddit  "sodium hyaluronate disassociates into hyaluronic acid molecule and a sodium atom in solution". 

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).

Also-called: HEC | What-it-does: viscosity controlling, emulsion stabilising

A nice little helper ingredient that can thicken up cosmetic products and create beautiful gel formulas. It's derived from cellulose, the major component of the cell wall of green plants. It is compatible with most co-ingredients and gives a very good slip to the formulas. 

What-it-does: viscosity controlling

We don't have description for this ingredient yet.

It's one of the most commonly used thickeners and emulsion stabilizers. If the product is too runny, a little xanthan gum will make it more gel-like. Used alone, it can make the formula sticky and it is a good team player so it is usually combined with other thickeners and so-called rheology modifiers (helper ingredients that adjust the flow and thus the feel of the formula). The typical use level of Xantha Gum is below 1%, it is usually in the 0.1-0.5% range. 

Btw, Xanthan gum is all natural, a chain of sugar molecules (polysaccharide) produced from individual sugar molecules (glucose and sucrose) via fermentation. It’s approved by Ecocert and also used in the food industry (E415). 

What-it-does: preservative, deodorant

If you have spotted ethylhexylglycerin on the ingredient list, most probably you will see there also the current IT-preservative, phenoxyethanol. They are good friends because ethylhexylglycerin can boost the effectiveness of phenoxyethanol (and other preservatives) and as an added bonus it feels nice on the skin too.

Also, it's an effective deodorant and a medium spreading emollient

What-it-does: viscosity controlling

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

What-it-does: buffering

Citric acid comes from citrus fruits and is an AHA. If these magic three letters don’t tell you anything, click here and read our detailed description on glycolic acid, the most famous AHA. 

So citric acid is an exfoliant, that can - just like other AHAs - gently lift off the dead skin cells of your skin and make it more smooth and fresh. 

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. 

Biosaccharide Gum-1 is a pretty interesting kind of sugar ingredient that is created from sorbitol via bacterial fermentation. 

According to the manufacturer it’s a “S.M.A.R.T.” sugar: it has Soothing, Moisturizing, Anti-aging, Restructuring and Touch properties. Let’s look at them quickly one by one.

Soothing: the manufacturer tested out the soothing effect in vivo (meaning on humans that is always a good thing!) by measuring how 3% Biosaccharide Gum-1 decreased the tingling sensation caused by 10% lactic acid. The result was good: the tingling was decreased by 47%.

Moisturizing: Compared to famous hyaluronic acid, it turns out that the two are great together. HA has a quicker effect and provides more instant hydration (much more hydration was measured after 1h of application), while our nice sugar has a somewhat delayed effect demonstrating stronger hydration after 3h of application. After 8 hours both had similar moisturizing effect. 

Anti-aging: According to ex-vivo tests (meaning not on humans, so do not trust it too much) Biosaccharide Gum-1 can stimulate a protein in our skin called sirtuin-1. This is supposed to help our skin cells to live longer, and function better. 

Resurfacing:  The sirtuin-1 stimulation also results in quicker cell renewal - something that happens anyway but slows down as we age. And the quicker cell renewal is good because it helps the regeneration of the barrier function. That is especially nice for fragile, sensitive skin.

Touch: our fermented sugar is not only good to the skin, but it also feels great on the skin. It gives a nice “soft touch” feeling and makes the products pleasant to use. 

The bottom line is that the above info is from the manufacturer (and we could not find any relevant independent research) so obviously take it with a grain of salt. But Biosaccharide Gum-1 does look as an interesting and promising ingredient that’s why it earned our goodie rating. 

What-it-does: preservative

A mild, natural preservative that usually comes to the formula together with its other mild preservative friends, such as Benzoic Acid and/or Dehydroacetic Acid. Btw, it's also used as a food preservative.

What-it-does: moisturizer/humectant

We don't have description for this ingredient yet.

What-it-does: moisturizer/humectant

We don't have description for this ingredient yet.

Zinc Pca - goodie

If you have oily, acne-prone skin, Zinc PCA is one of the actives to put on your "TO TRY" list.

It's a synergistic association of two great things: Zinc and L-PCA. The Zinc part is there to help normalize sebum production and limit the proliferation of evil acne-causing bacteria. L-PCA stands for pyrrolidone carboxylic acid and it's a key molecule in the skin that helps with processes of hydration and energy (it's actually an NMF, a natural moisturizing factor).

L-PCA is not only there to hydrate the skin, but it also helps to increase the efficacy and bioavailability of zinc. An in-vivo (done on real people) test done by the manufacturer shows that Zinc PCA reduces sebum production statistically significantly after 28 days of application (1% was used in the test), and in-vitro (made in the lab) measurements show that Zinc PCA has strong anti-microbial activity against P. acnes (between 0.1-0.25%) and other bacterial strains.

If that would not be enough there is also a 2011 research paper saying that based on in-vitro (made in the lab, not on real people)  findings Zinc PCA might be a promising anti-aging active that helps with the production of type I collagen (and we all know more collagen = firmer skin). 

All in all, definitely a goodie for oily, acne-prone skin

What-it-does: viscosity controlling

A natural polysaccharide (big sugar molecule) coming from red edible seaweeds. It is used as a helper ingredient for its gelling, thickening and stabilizing properties.  

Lecithin - goodie
What-it-does: emollient, emulsifying

A very common ingredient that can be found in all cell membranes. In cosmetics it's quite the multi-tasker: it's an emollient and water-binding ingredient but it's also an emulsifier and can be used for stabilization purposes. It's also often used to create liposomes

What-it-does: preservative

It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It’s not a strong one and doesn’t really work against bacteria, but more against mold and yeast. To do that it has to break down to its active form, sorbic acid. For that to happen, there has to be water in the product and the right pH value (pH 3-4). 

But even if everything is right, it’s not enough on its own. If you see potassium sorbate you should see some other preservative next to it too.

BTW, it’s also a food preservative and even has an E number, E202.

Also-called: Maris Sal

We don't have description for this ingredient yet.

What-it-does: antioxidant

We don't have description for this ingredient yet.

What-it-does: preservative

It’s pretty much the current IT-preservative. It’s safe and gentle, but even more importantly, it’s not a feared-by-everyone-mostly-without-scientific-reason paraben.

It’s not something new: it was introduced around 1950 and today it can be used up to 1% worldwide. It can be found in nature - in green tea - but the version used in cosmetics is synthetic. 

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.

Also-called: Fragrance, Parfum | What-it-does: perfuming

Exactly what it sounds: nice smelling stuff put into cosmetic products so that the end product also smells nice. Fragrance in the US and parfum in the EU is a generic term on the ingredient list that is made up of 30 to 50 chemicals on average (but it can have as much as 200 components!). 

If you are someone who likes to know what you put on your face then fragrance is not your best friend - there's no way to know what’s really in it.  

Also, if your skin is sensitive, fragrance is again not your best friend. It’s the number one cause of contact allergy to cosmetics. It’s definitely a smart thing to avoid with sensitive skin (and fragrance of any type - natural is just as allergic as synthetic, if not worse!). 

Linalool - icky
What-it-does: perfuming, deodorant

Linalool is a super common fragrance ingredient. It’s kind of everywhere - both in plants and in cosmetic products. It’s part of 200 natural oils including lavender, ylang-ylang, bergamot, jasmine, geranium and it can be found in 90-95% of prestige perfumes on the market. 

The problem with linalool is, that just like limonene it oxidises on air exposure and becomes allergenic. That’s why a product containing linalool that has been opened for several months is more likely to be allergenic than a fresh one.

A study made in the UK with 483 people tested the allergic reaction to 3% oxidised linalool and 2.3% had positive test results. 

Geraniol - icky
What-it-does: perfuming

Geraniol is a common fragrance ingredient. It smells like rose and can be found in rose oil or in small quantities in geranium, lemon and many other essential oils. 

Just like other similar fragrance ingredients (like linalool and limonene) geraniol also oxidises on air exposure and becomes allergenic. Best to avoid if you have sensitive skin.

What-it-does: perfuming

Citronellol is a very common fragrance ingredient with a nice rose-like odor. In the UK, it’s actually the third most often listed perfume on the ingredient lists. 

It can be naturally found in geranium oil (about 30%) or rose oil (about 25%). 

As with all fragrance ingredients, citronellol can also cause allergic contact dermatitis and should be avoided if you have perfume allergy. In a 2001 worldwide study with 178 people with known sensitization to fragrances citronellol tested positive in 5.6% of the cases.

There is no known anti-aging or positive skin benefits of the ingredient. It’s in our products to make it smell nice. 

What-it-does: perfuming

A common fragrance ingredient that smells like jasmine. It is one of the “EU 26 fragrances” that has to be labelled separately because of allergen potential. Best to avoid if your skin is sensitive.

Also-called: Lilial | What-it-does: perfuming

A common fragrance ingredient that has a nice floral scent and also goes by the name Lilial. It’s one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” on the label) because of allergen potential. Best to avoid if your skin is sensitive. 

What-it-does: perfuming

It’s a common fragrance ingredient that is one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” on the label) because of allergen potential. Best to avoid if your skin is sensitive.

Coumarin - icky
What-it-does: perfuming

A common fragrance ingredient that has a sweet, vanilla, nutty scent. When diluted it smells like freshly-mown hay.

It’s one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” on the label) because of allergen potential. Best to avoid if your skin is sensitive.

Limonene - icky
What-it-does: perfuming, solvent, deodorant

A super common and cheap fragrance ingredient. It's in many plants, e.g. rosemary, eucalyptus, lavender, lemongrass, peppermint and it's the main component (about 50-90%) of the peel oil of citrus fruits.

It does smell nice but the problem is that it oxidizes on air exposure and the resulting stuff is not good for the skin. Oxidized limonene can cause allergic contact dermatitis and counts as a frequent skin sensitizer

Limonene's nr1 function is definitely being a fragrance component, but there are several studies showing that it's also a penetration enhancer, mainly for oil-loving components.

All in all, limonene has some pros and cons, but - especially if your skin is sensitive - the cons probably outweigh the pros.  

Eugenol - icky
What-it-does: perfuming

A colorless or yellowish oil that's used as a fragrance. It has a spicy scent and can be found for example in basil, clove or cinnamon oil.

A 2006 in-vitro  (made in the lab not on real people) study examined if clove oil is cytotoxic and found that not only clove oil but also its main constituent, eugenol is cytotoxic even at very low concentration (0.03%). It’s also one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” on the label) because of allergen potential. Best to avoid at least in leave-on products.

Also-called: CI 77019 | What-it-does: colorant

A super versatile and common mineral powder that comes in different particle sizes. It is a multi-tasker used to improve skin feel, increase product slip, give the product light-reflecting properties, enhance skin adhesion or serve as an anti-caking agent.

It is also the most commonly used "base" material for layered composite pigments such as pearl-effect pigments. In this case, mica is coated with one or more metal oxides (most commonly titanium dioxide) to achieve pearl effect via the physical phenomenon known as interference. 

Also-called: Titanium Dioxide/Ci 77891;Ci 77891 | What-it-does: colorant | Irritancy: 0 | Comedogenicity: 0

Ci 77891 is the color code of titanium dioxide. It's a white pigment with great color consistency and dispersibility.

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what‑it‑does solvent
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what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
A real oldie but a goodie. Great natural moisturizer and skin-identical ingredient that plays an important role in skin hydration and general skin health. [more]
what‑it‑does solvent | moisturizer/humectant
A natural corn sugar derived glycol. It can be used to improve skin moisturization, as a solvent, to boost preservative efficacy or to influence the sensory properties of the end formula. [more]
what‑it‑does antioxidant | skin brightening
A stable, oil-soluble form of Vitamin C, that might have (in-vitro results) all the magic abilities of pure vitamin C (antioxidant, collagen booster, skin brightener). [more]
what‑it‑does moisturizer/humectant
Saccharomyces cerevisiae (SC)  is the fancy name for common baker’s yeast.  Usually different kind of yeast extracts are used in skincare for their great hydrating, and general skin conditioning properties. [more]
what‑it‑does perfuming
Mountain Arnica Extract - Most famously used to treat bruisings, though the scientific basis for its effectiveness is questionable. [more]
what‑it‑does antioxidant | soothing
Green Tea - one of the most researched natural ingredients that contains the superstar actives called catechins. It has proven antioxidant, anti-inflammatory, antimicrobial and anticarcinogenic properties. [more]
what‑it‑does exfoliant | antioxidant
It's a liquid extract coming from grape. It works as a skin peeling agent as it contains about 40% of AHA acids. [more]
what‑it‑does moisturizer/humectant
A silky clear liquid that has great moisturizing, skin protecting and film-forming properties on the skin. [more]
what‑it‑does soothing
what‑it‑does abrasive/scrub | emollient
what‑it‑does soothing
what‑it‑does antioxidant
what‑it‑does antioxidant
what‑it‑does cell-communicating ingredient
irritancy, com. 1-3, 1-3
An ester form of vitamin A (retinol + palmitic acid) that is pretty much the least effective member of the retinoid family. Its anti-aging effects are quite questionable as well as its behavior in the presence of UVA light. (Use it at night if possible!) [more]
what‑it‑does antioxidant
irritancy, com. 0, 0
A form of vitamin E that works as an antioxidant. Compared to the pure form it's more stable, has longer shelf life, but it's also more poorly absorbed by the skin. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
It's the salt form of famous humectant and natural moisturizing factor, hyaluronic acid. It can bind huge amounts of water and it's pretty much the current IT-moisturizer. [more]
what‑it‑does viscosity controlling
A nice little helper ingredient that can thicken up cosmetic products and create beautiful gel formulas. It's derived from cellulose, the major component of the cell wall of green plants. [more]
what‑it‑does viscosity controlling
what‑it‑does viscosity controlling
A super commonly used thickener and emulsion stabilizer. [more]
what‑it‑does preservative
It can boost the effectiveness of phenoxyethanol (and other preservatives) and as an added bonus it feels nice on the skin too. [more]
what‑it‑does viscosity controlling
what‑it‑does buffering
An AHA that comes from citrus fruits. It is usually used as a helper ingredient to adjust the pH of the formula. [more]
what‑it‑does soothing | moisturizer/humectant
Biosaccharide Gum-1 is a pretty interesting kind of sugar ingredient that is created from sorbitol via bacterial fermentation.  According to the manufacturer it’s a “S.M.A.R.T.” sugar: [more]
what‑it‑does preservative
A mild, natural preservative that usually comes to the formula together with its other mild preservative friends, such as Benzoic Acid and/or Dehydroacetic Acid. [more]
what‑it‑does moisturizer/humectant
what‑it‑does moisturizer/humectant
what‑it‑does anti-acne | moisturizer/humectant
A synergistic combination of Zinc and l-PCA that can reduce sebum production and limit the proliferation of evil acne-causing bacteria. A goodie for oily, acne-prone skin. [more]
what‑it‑does viscosity controlling
A natural polysaccharide (big sugar molecule) coming from red edible seaweeds. It is used as a helper ingredient for its gelling, thickening and stabilizing properties. [more]
what‑it‑does emollient | emulsifying
It's quite the multi-tasker: an emollient and water-binding ingredient but also an emulsifier and can be used for stabilization purposes. It's also often used to create liposomes.  [more]
what‑it‑does preservative
A not so strong preservative that doesn’t really work against bacteria, but more against mold and yeast. [more]
what‑it‑does antioxidant
what‑it‑does preservative
Pretty much the current IT-preservative. It’s safe and gentle, and can be used up to 1% worldwide. [more]
what‑it‑does perfuming
The generic term for nice smelling stuff put into cosmetic products so that the end product also smells nice. It is made up of 30 to 50 chemicals on average. [more]
what‑it‑does perfuming
A super common fragrance ingredient that can be found among others in lavender, ylang-ylang, bergamot or jasmine. The downside of it is that it oxidises on air exposure and might become allergenic. [more]
what‑it‑does perfuming
A common fragrance ingredient that smells like rose and can be found in rose oil. [more]
what‑it‑does perfuming
A common fragrance ingredient with a nice rose-like smell. [more]
what‑it‑does perfuming
A common fragrance ingredient that smells like jasmine. It is one of the “EU 26 fragrances” that has to be labelled separately because of allergen potential. [more]
what‑it‑does perfuming
A common fragrance ingredient that has a nice floral scent and also goes by the name Lilial. It’s one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” [more]
what‑it‑does perfuming
It’s a common fragrance ingredient that is one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” [more]
what‑it‑does perfuming
A common fragrance ingredient that has a sweet, vanilla, nutty scent. When diluted it smells like freshly-mown hay. [more]
what‑it‑does perfuming | solvent
A super common fragrance ingredient found naturally in many plants including citrus peel oils, rosemary or lavender. It autoxidizes on air exposure and counts as a common skin sensitizer. [more]
what‑it‑does perfuming
A colorless or yellowish oil that's used as a fragrance with a spicy scent. [more]
what‑it‑does colorant
A mineral powder used to improve skin feel, increase product slip, give the product some light-reflecting properties, enhance skin adhesion or serve as an anti-caking agent. A real multi-tasker. [more]
what‑it‑does colorant
irritancy, com. 0, 0
Titanium dioxide as a colorant. It's a white pigment with great color consistency and dispersibility.