Sleek'E Silk'e Leave-In Conditioner
A leave-in conditioner with 16 ingredients, including vitamin C.
Leave-in conditioner with 16 ingredients that contains Vitamin C
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What's inside
Ingredients List
Water
Skin ConditioningPolyquaternium-37
Hydroxyethylcellulose
Emulsion StabilisingPEG-2m
Emulsion StabilisingPolyquaternium-39
Oleyl Alcohol
EmollientDimethicone
EmollientCyclopentasiloxane
EmollientSimmondsia Chinensis Seed Oil
EmollientLysine Hcl
Skin ConditioningCitric Acid
BufferingDisodium EDTA-Copper
AstringentAscorbic Acid
AntioxidantAloe Barbadensis Leaf Extract
EmollientPhenoxyethanol
PreservativeParfum
MaskingKey Ingredients
Benefits
Concerns
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 WaterWe don't have a description for Polyquaternium-37 yet.
Hydroxyethylcellulose is used to improve the texture of products. It is created from a chemical reaction involving ethylene oxide and alkali-cellulose. Cellulose is a sugar found in plant cell walls and help give plants structure.
This ingredient helps stabilize products by preventing ingredients from separating. It can also help thicken the texture of a product.
This ingredient can also be found in pill medicines to help our bodies digest other ingredients.
Learn more about HydroxyethylcelluloseWe don't have a description for PEG-2m yet.
We don't have a description for Polyquaternium-39 yet.
Oleyl Alcohol is a type of fatty alcohol made from oleic acid.
Fatty Alcohols are most often used as an emollient or to thicken a product. They are usually derived from natural fats and oils and therefore do not have the same drying or irritating effect as solvent alcohols.
Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.
What it does:
Dimethicone comes in different viscosities:
Depending on the viscosity, dimethicone has different properties.
Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.
This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.
Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.
Learn more about DimethiconeCyclopentasiloxane (D5) is a lightweight silicone that mostly acts as an emollient and solvent in cosmetics. Its the reason your products feel silky, fast-spreading, and non-greasy.
Since D5 is volatile, it does its thing and then evaporates off the skin quickly.
The safety profile of this ingredient is reassuring; the US CIR Expert Panel concluded D5 is safe as used in cosmetics and Health Canada concluded that D5 is not harmful to human health or the environment as currently used in cosmetics
There's a study that people mention about D5 in a rat study showing tumors. This study is related to long-term inhalation of high D5 levels.
Regulatory bodies have judged this study to be not applicable in topical skincare since skin absorption of D5 is very low and we're not really inhaling huge amounts of D5.
The only restriction for this ingredient is environmental. The European Chemicals Agency (ECHA) restricted D5 in wash-off cosmetics at or above 0.1% due to their persistence in water.
Learn more about CyclopentasiloxaneJojoba oil is one of the most well-studied plant-derived ingredients in cosmetics. It is an emollient with a special structure.
Because it is made up of 97-98% wax esters, it closely mirrors the linear monoesters found in human sebum. This makes it skin compatible, non-greasy, and lightweight.
Unlike other plant oils, jojoba wax doesn't easily penetrate skin. It mostly works in the uppermost layers as an emollient. This just means it forms a light barrier on the skin to help retain moisture.
Formulations with jojoba esters up to 90% reduced transepidermal water loss (TEWL) and increased barrier recovery by 81% (outperforming bisabolol at 47%).
Besides barrier support, the science also suggests jojoba to have anti-inflammatory effects and potential applications for skin infections, aging, and wound healing.
Fun fact: Indigenous cultures have used jojoba as a moisturizer and to help treat burns for centuries.
Fungal acne: The Malassezia yeast is known to metabolize fatty acids in the C11-24 range and jojoba's dominant fatty acid components fall into this range. This ingredient may not be fungal acne safe.
Learn more about Simmondsia Chinensis Seed OilLysine HCl is an alpha amino acid salt.
Our skin uses amino acids as a precursor for building protein, and therefore keratins, collagen and elastin.
Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.
However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.
In skincare formulas, citric acid can:
While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.
Read more about some other popular AHA's here:
Learn more about Citric AcidWe don't have a description for Disodium EDTA-Copper yet.
Ascorbic 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 AcidAloe Barbadensis Leaf Extract is a botanical extract pulled from the leaves of aloe vera and one of the most studied plant ingredients in cosmetics.
The inner leaf gel it comes from is mostly water (~99-99.5%) and the remaining fraction is made up of pretty good stuff: polysaccharides, vitamins, phenolics, and enzymes.
Its headline job is hydration.
The star polysaccharide in aloe, acemannan, is a humectant that retains moisture and helps reduce trans-epidermal water loss.
Aloe also has real soothing credentials; it contains anti-inflammatory compounds like bradykinase and C-glucosyl chromone that help calm irritation and redness.
On the repair side, lab work shows that acemannan wakes up your skin's repair cells (fibroblasts), prompting them to multiply and speed up healing.
There's some human data for cosmetic benefit too: a cream containing 10% Aloe Barbadensis leaf extract improved skin hydration and elasticity in a real-use study.
Safety-wise, this ingredient is well-regarded with just one rare downside; there have been some case reports of acute eczema, contact urticaria, and dermatitis in people who applied aloe-derived ingredients topically. Those with a known aloe or Liliaceae sensitivity should patch test.
Typical use levels range widely, from under 1% up to 90%+ depending on the format and the effect you are after.
Learn more about Aloe Barbadensis Leaf ExtractPhenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
It has a large spectrum of antimicrobial activity and especially effective bacteria, yeast, and mold while only having a weak effect on your skin's natural microbiome.
On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.
Another perk of this ingredient is that it stays functional across a wide pH range (3-10).
You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.
Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.
Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.
Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.
Learn more about PhenoxyethanolParfum is a catch-all term for an ingredient or more that is used to give a scent to products.
Also called "fragrance", this ingredient can be a blend of hundreds of chemicals or plant oils. This means every product with "fragrance" or "parfum" in the ingredients list is a different mixture.
For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations.
The term 'parfum' or 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.
For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance by INCI standards.
One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.
Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.
Parfum can also be used to mask or cover an unpleasant scent.
The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.
Learn more about ParfumReviews
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Where it's from
Sleek'E is a American brand
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The data we've presented on this page has been verified by a member of the SkinSort Team.
Read more about us· Updated January 3, 2025 • Added by BlackCat808