Hautsache Vitamin C Serum
A serum with 14 ingredients, including vitamin C.
This brightening serum is formulated around Ascorbic Acid and Ergothioneine to fade the look of dark spots and brighten dull-looking skin.
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What's inside
Key Ingredients
Benefits
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Ingredients Explained
Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.
So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!
Learn more about WaterAscorbic Acid is is pure Vitamin C and is the biologically active form used directly by skin.
Not only is vitamin C great for your overall health and immune system, but it also has plenty of benefits for your skin. It is best supported by academic literature for:
Topical vitamin C has been shown to help neutralize oxidative stress from UV and pollution, helping to improve photoaging and hyperpigmentation when used consistently.
One clinical study found that using 5% topical vitamin C for six months improved signs of photodamaged skin, both on the surface and in the deeper structural layers of the skin.
While vitamin C doesn’t replace sunscreen, studies show it can boost photoprotection when combined with Vitamin E and ferulic acid. These two ingredients help improve stability and protective effects.
The big downside of this ingredient is formulation difficulty. Vitamin C is prone to oxidation and doesn't penetrate the skin unless formulated correctly. Research found that vitamin C absorbs into the skin best at a low pH (< 3.5) with about 20% being the upper limit for effective absorption.
Skin levels can saturate after repeated application; this means your skin won’t keep absorbing more once it’s full of vitamin C. This is why more isn’t always better with vitamin C and why very high concentrations don’t necessarily give extra benefits.
Ascorbic acid generally works well with many skincare ingredients but can be irritating when combined with other active ingredients. Strong oxidizing acne treatments like benzoyl peroxide can reduce the effectiveness of vitamin C if they are used at the same time; they are often recommended for use at different times of day.
Read more about other types of Vitamin C:
Foods rich with vitamin C include oranges, strawberries, broccoli, bell peppers, and more. When consuming Vitamin C, your skin receives a portion of the nutrients.
Learn more about Ascorbic AcidPentylene Glycol (1,2-pentanediol) is a multitasking little diol with three main roles in a formula:
Research on alkanediols (the family pentylene glycol belongs to) show they work by disrupting microbial cell membranes. This disruption helps the primary preservative system in a product work more effectively at lower doses.
On the safety side, the Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe as used in current cosmetic practices + concentrations.
Typical use levels in a formula run about 1-5%.
Learn more about Pentylene GlycolEthoxydiglycol (aka Diethylene Glycol Monoethyl Ether) is one of the cosmetic world's quiet problem solvers.
In a formula, it is a solvent that dissolves tricky ingredients that don't want to mix in and helps spread ingredients evenly across your skin without leaving a greasy or sticky feeling
This makes it great for hard-to-dissolve actives like vitamin C, benzoyl peroxide, and self-tanner DHA.
It also has mild humectant and penetration enhancer abilities so it can help some actives absorb a little deeper.
The penetration boost is backed by lab research: studies using human skin samples found it improved how well an active dissolves into the upper layer of skin rather than tearing down your skin barrier. Reviews of its mechanism also describe it interacting gently with the lipids and water in your outermost layer of skin.
Just know this penetration-enhancing effect is not universal. It helps a lot in some formulas and did very little in others (so the benefit really depends on the specific product).
Safety-wise, the evidence is reassuring. The Cosmetic Ingredient Review Expert Panel reviewed it and concluded it's safe for use in cosmetics and recognized it as non-irritating, non-sensitizing, and non-comedogenic in skincare.
Typical leave-on skincare usage lands around 1-10%. The EU has sets caps of 2.6% in non-spray products, 10% in rinse-offs, 7% in oxidative hair dye, and 5% in non-oxidative hair dye.
Learn more about EthoxydiglycolThis ingredient is also known as sweet almond oil. It is a lightweight, cold-pressed oil from the ripe seeds of the sweet almond tree.
Sweet almond oil is rich in skin-nourishing fatty acids such as oleic acid (55-86%) and linolenic acid (7-35%).
As an emollient, it softens and hydrates skin by forming a thin barrier that locks in moisture.
Clinical studies have found it to be non-irritating and non-sensitizing. The CIR Expert Panel has evaluated the available safety data and concluded it is safe for topical use.
Because of the oleic acid content, this ingredient may not be fungal acne safe.
Learn more about Prunus Amygdalus Dulcis OilSodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.
In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.
Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.
"Alkaline" refers to a high pH level. A low pH level would be considered acidic.
Learn more about Sodium HydroxideSclerotium Gum is a natural sugar-based fiber made by fermenting a fungus called Sclerotium rolfsii. It's often used as the plant-friendly alternative for synthetic thickeners like carbomer.
In skincare, it works as a thickener, gel former, and stabilizer that keeps heavy ingredients suspended so a product does not separate.
It is non-ionic and forms a triple helix in solution. This is just a fancy way of saying it builds a smooth, cushiony, and non-sticky gel that feels silkier than many other gums.
Another perk of this ingredient is that it is very sturdy and holds up across a wide pH range (~2-11). It's also good at resisting heat and hydrolysis.
Since it holds water at the skin surface, it can provide some light hydration as well.
Typical use levels are around 0.25-2%; formulators usually use 0.2-0.5% to thicken lotions and up to 2% for a firmer gel base.
This ingredient has been found safe in cosmetics with no meaningful evidence of skin sensitization.
Learn more about Sclerotium GumPolyglyceryl-3 Cocoate isn't fungal acne safe. It can be bad for dry skin.
Polyglyceryl-4 Caprate comes from Capric Acid and Polyglycerin-4. It is an emulsifier.
Emulsifiers help stabilize a product. They do this by preventing ingredients from separating, such as oils and water which do not mix naturally.
Polyglyceryl-6 Caprylate comes from caprylic acid and Polyglycerin-6. It is an emulsifier, emollient, and cleansing agent.
Emulsifiers help stabilize a product. It does this by preventing certain ingredients from separating. Common ingredients include oils and water, which do not mix naturally. Emulsifiers have properties that help keep ingredients such as these together. There is emerging research that shows emulsifiers may also help in delivering ingredients into the skin.
As an emollient, polyglyceryl-6 caprylate helps soften skin.
Learn more about Polyglyceryl-6 CaprylatePolyglyceryl-6 Ricinoleate isn't fungal acne safe.
Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.
On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.
Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.
Learn more about Xanthan GumMannitol is a sugar alcohol. It is a humectant and moisturizes the skin. In vitro (not tested on a living organism), mannitol displays antioxidant properties.
When found in aqueous solutions, mannitol tends to become acidic. This is because it loses a hydrogen ion. This is why mannitol can often be found with pH adjusting ingredients, such as sodium bicarbonate.
Fun fact: Mannitol can be found in foods as a sweetener. It can be naturally found in mushrooms, algae, fruits, and veggies.
Learn more about MannitolErgothioneine is an amino acid found naturally in mushrooms, grains, and meat. It has antioxidant and skin soothing properties.
This amino acid helps with:
- Maintaining DNA stability and cell reproduction
- Enhances cellular immunity
- Skin brightening
- Anti-aging
- Skin soothing
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Hautsache is a German brand
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