Estée Lauder Re-Nutriv Ultimate Lift Regenerating Youth Emulsion

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

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.

Pro tip: Use occlusives, such as this ingredient, on damp skin for the best results.

The quality or origin of petrolatum is only known when disclosed by the brand. Most cosmetic petrolatum has gone through several purification stages.

Another benefit of occlusives is it protects your skin against infection or allergies.

Petrolatum is fungal acne safe. It is a hydrocarbon with no fatty acid structure, so Malassezia cannot metabolize it. In-vitro studies support negligible growth stimulation as well.

It's also worth noting that petrolatum has a comedogenic rating of 0. In updated rabbit ear testing (and in human testing), petrolatum was found to be not comedogenic. This means it didn’t promote comedone formation in standard models.

This ingredient is typically used in concentrations between 1-10%. Studies have found it to be non-sensitizing, non-phototoxic, and non-photoallergenic.

A close cousin of this ingredient is Glyceryl Stearate SE ("self-emulsifying"). This just has a small amount of sodium or potassium stearate added so it can emulsify without a co-emulsifier.

Since this ingredient is an ester of a C18 fatty acid, it may not be fungal acne safe. The Malassezia yeast can potentially metabolize within the C11-C24 range.

Fun fact: The human body also creates Glyceryl Stearate naturally.

Emollients help your skin stay smooth and soft. It does so by creating a film on top of the skin that helps trap moisture in.

As an emollient, it helps trap moisture in the skin. It is considered an occlusive.

This is a great ingredient for dry, compromised, or aging skin; our skin starts to produce less cholesterol with age.

Research shows cholesterol works best in combination with ceramides and fatty acids, the other two major components in your skin barrier.

Cholesterol is also a well-establish penetration enhancer and can help other actives absorb more effectively.

Cosmetic-grade cholesterol is usually derived from lanolin but plant and synthetic options also exist. We recommend reaching out to the brand if you have questions about their source of cholesterol.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

Beyond smoothing, Argireline may also support collagen production. Collagen is the protein that helps keep your skin firm, bouncy, and well-hydrated by strengthening the skin barrier.

So while Argireline isn’t a miracle fix, it can be a helpful addition to a routine focused on both prevention and skin health.

Read more about other common types of peptides here:

Preclinical research has found that topical avocado oil increased collagen synthesis and reduced inflammation during wound healing, giving it some skin-repairing credibility.

The unsaponifiable fraction of the oil is also interesting: studies on avocado unsaponifiables showed that it helped skin produce more collagen and other structural compounds that support healing.

The CIR Expert Panel has found this ingredient to be non-irritating in formulations.

It's a great ingredient for dry or compromised skin. Just know it may not be fungal acne safe. This is because the oleic acid content falls within the range that Malassezia can use as a food source.

This ingredient is rich in amino acids, proteins, sugars, and vitamins. Small amounts of minerals such as phosphorous, iron, potassium, and copper are also found the seaweed.

These components help hydrate and nourish your skin's natural barrier. Having a healthy skin barrier leads to more youthful looking skin and may help reduce the signs of aging.

Laminaria Digitata is found in the northern Atlantic Ocean.

What's the difference between algae and seaweed?
Algae is a broad term that includes seaweed. Not all algae is seaweed.

Due to this fatty acid content, this ingredient may not be fungal-acne safe.

While lab studies suggest gold nanoparticles may have anti-inflammatory or antioxidant potential, there is limited high-quality human evidence showing clear skin benefits at typical cosmetic use levels.

The EU has raised safety concerns around gold nanomaterials due to insufficient data on skin penetration and long term exposure. Additionally, gold is a known contact allergen. This means it may trigger irritation or allergic reactions in individuals sensitive to gold.

In the EU, gold is listed as CI 77480 and only permitted for use as a cosmetic colorant. The US and FDA does not list it as an approved cosmetic color additive. This affects how products that contain gold are labeled or formulated in the US market.

Studies show pearls can aid in wound healing.

Pearls are harvested from oysters. To be vegan, an ingredient cannot be from an animal source.

The root of the plant has been used in traditional folk medicine throughout Asia.

AAP has been shown to help reduce signs of hyperigmentation and age-spots.

AAP is water soluble.

Vitamin C can help to reduce redness, improve skin texture, reduce the effects of aging, and reduce the visibility of dark spots.

Read more about other types of Vitamin C:

Studies show green tea extract and its catechins (like epigallocatechin gallate (EGCG)) help your skin cells product energy more efficiently and reducing the number of free-radicals that can damage your skin from the inside.

In lab-grown skin models, this translated to younger, healthier, and stronger skin.

There's also good sun protection data; researchers saw less DNA damage and redness on human skin when green tea was applied before UVB exposure. And the more they applied, the better the protection.

Needless to say, this ingredient shouldn't replace your sunscreen. But it is a great supportive ingredient that you can already find in many sunscreens and antioxidant serums.

A 2009 study found a 2% green tea lotion was effective for mild-to-moderate acne thanks to its anti-inflammatory and mild antimicrobial activity.

The quality of the extract matters a lot here:

Good extracts contain 50-90% catechins while lower quality ones are mostly there for marketing. We recommend reaching out to the brand if you have questions about the quality or source of their ingredients.

Human Repeated Insult Patch Testing showed no irritation or sensitization at use concentrations (0.86% in leave-on products and up to 30% as leaf water).

A double-blind study confirmed that extra virgin coconut oil is as effective as mineral oil for treating very dry skin. Another study found it outperformed mineral oil for mild to moderate atopic dermatitis in children.

Another study from 2018 found that virgin coconut oil can soothe inflammation and boost key skin barrier proteins. Just know this evidence is still only from lab settings and not human trials.

It has also been shown to reduce Staphylococcus aureus, a bacteria that commonly overgrows in people with eczema.

Clinical testing shows very minimal skin irritation and no evidence of sensitization or phototoxicity.

Coconut oil gets flagged as a "fragrance" because it has a natural mild scent (not because it's a synthetic perfume). The European Cosmetic ingredient database also lists "perfuming" as a function of this ingredient.

Just so you know, the term "fragrance" is completely unregulated. Some brands still use botanical extracts or essential oils in their "fragrance-free" formulas, but regulatory databases technically classify these under "fragrance".

Coconut oil has a tiny and useless bit of natural SPF. Early lab studies clocked it around SPF 7-8 but a more recent study found the real number closer to SPF 1.2. It also offers no meaningful UVA protection (SPF only overs UVB rays).

The comedogenic rating of 4/5 means it has a high potential to clog pores; but it's worth noting that comedogenicity is highly individual and ratings cannot predict how an overall formula will behave on skin.

Since lauric acid is the dominant fatty acid, this ingredient may not be fungal acne safe. The Malassezia yeast feeds on fatty acids with carbon chain lengths between 11-24, and lauric acid falls within these lengths (C12).

Bioferments of yeast and soy have been found to reduce hyperpigmentation at low levels.

Due to its fatty acid content, this ingredient may not be fungal-acne safe.

Research shows:

A 1998 study did find that applying oleic acid at higher concentrations may cause irritation and disrupt the skin barrier. Modern formulations typically use low levels that is well-tolerated.

The culprit behind fungal acne, the Malassezia yeast, feeds on fatty acids with carbon chain lengths between C11-C24. Oleic Acid, at C18, falls right into that sweet spot.

In vitro studies have shown that Oleic Acid is one of the fatty acids that induce rapid Malassezia growth in lab settings.

When paired with niacinamide, Acetyl Glucosamine has been shown to be effective at reducing discoloration.

Algae is rich in antioxidants. Antioxidants help fight free-radicals. Free-radicals are molecules that may damage your skin cells, such as pollution.

Algae can also help with soothing and hydrating skin.

Many different types of algae have different benefits.

Tocopheryl Acetate is commonly found in both skincare and dietary supplements.

Due to its antioxidant properties, trehalose may help with signs of aging. Antioxidants help fight free-radical molecules, unstable molecules that may damage your skin.

In medicine, trehalose and hyaluronic acid are used to help treat dry eyes.

Some animals, plants, and bacteria create trehalose as a source of energy to survive freeze or lack of water.

Early research also shows that caffeine can help calm redness, soothe irritated skin, and support hair growth by stimulating microcirculation in the scalp.

You might have seen eye creams marketing caffeine as a depuffing ingredient. This is because it is a vasoconstrictor meaning it can temporarily constrict blood vessels, though clinical evidence for this specific use is still limited.

Most skincare products contain this ingredient at concentrations between 1-6%. It is able to penetrate skin easily regardless of skin type or thickness.

Just so you know, a very small number of case reports describe caffeine-induced allergy. This ingredient is generally well-tolerated, non-irritating, and non-sensitizing for the majority of people.

It doesn’t protect you from the sun, but it can help your skin bounce back after too much time in it.

Let’s get into the details:

Aloe contains antioxidant Vitamins A, C, and E, which help fight off free radicals (unstable molecules from things like pollution that can damage your skin).

It’s also rich in polysaccharides, which are natural sugars that help hydrate the skin by acting like the skin’s own moisturizing agents. These, along with other sugars like monosaccharides, help form a protective barrier that locks in moisture.

Aloe works as both a humectant and an emollient. That means it draws water into the skin (humectant) and helps trap it there (emollient), making it an effective natural moisturizer.

You’ll also find a mix of other skin-supporting ingredients in aloe, including folic acid, choline, calcium, amino acids, fatty acids, and even Vitamin B12.

Out of the 420+ species of aloe, Aloe barbadensis is the most widely used in skincare products thanks to its gentle yet effective properties.

There are over 420 species of aloe but Aloe Barbadensis is the most commonly used for topical products.

Saccharomyces is also known as brewer's yeast and was traditionally used to make beer.

It's worth knowing sugars are already a natural component of the skin's NMF (natural moisturizing factor) so it's a molecule that your stratum corneum is well-acquainted with.

Just so you know, glucose is hydrophilic (water-loving) and the stratum corneum is a strong barrier to hydrophilic compounds. This just means penetration is slow and most of the action is happening on the surface.

Gram-to-gram, glucose is not as efficient as a humectant as glycerin. This is why you'll likely see glycose paired with stronger humectants for a bigger hydration payoff.

In skincare, glucose is typically derived from corn or other starch sources.

D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.

Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):

Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.

This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.

Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.

This ingredient is also referred to as pro-vitamin B5.

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:

Though it has "alcohol" in the name, it is not related to denatured alcohol or ethyl alcohol.

The FDA allows products labeled "alcohol-free" to have fatty alcohols.

Because it is not a free-fatty acid or alcohol, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

One thing worth noting: a controlled study found this ingredient applied under occlusion to acne-prone subjects increased microcomedones. Just keep in mind this was under occlusive conditions and don't reflect how most products are used day-to-day.

For most people, this is a well-tolerated and lightweight ingredient.

This ingredient may not be fungal acne safe because it is a fatty acid ester.

Isohexadecane is often used in products designed to help oily skin. It is lightweight and non-greasy while helping to moisturize. When mixed with silicones, it gives a product a silky feel.

One component, glabridin, has extra potent antioxidant and soothing properties. It has also been found to block pigmentation from UVB rays in guinea pigs.

Licorice Root also contains a flavonoid. Flavonoids are a natural substance from in plants. Flavonoids also have antioxidant properties.

Another component, glycyrrhizin, has been found to have anti-inflammatory and antimicrobial benefits. This may make licorice root extract effective at treating acne. However, more research is needed to support this.

Liquiritin is one of the flavone compounds found in licorice. It has been found to help lighten skin by preventing tyrosinase from reacting with tyrosine. When the two react, protein is converted to melanin. Melanin is the substance in your body that gives your features pigmentation.

Licorice root is native to Southern Europe and Asia. It has been used in traditional Chinese medicine to help with respiratory issues.

Polysorbate 80 may not be fungal acne safe.

A high amount of carbomer can cause pilling or balling up of products. Don't worry, most products contain 1% or less of carbomer.

Polymethylsilsesquioxane has not been shown to clog pores. It has been deemed safe to use up to 55%, but most cosmetics use much less.

If you have concerns about using this ingredient, we recommend speaking with a professional.

Both potassium sorbate and sorbic acid can be found in baked goods, cheeses, dried meats, dried fruit, ice cream, pickles, wine, yogurt, and more.

You'll often find this ingredient used with other preservatives.

The manufacturer also claims this ingredient to be useful in makeup.

In lipstick formulations, this ingredient improves color payoff, reduces pigment settling, and reduces oil bleeding. This ingredient also improves the grip of powder products such as dry shampoos.

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.

The unique structure of silica enhances the spreadability and adds smoothness, making it a great texture enhancer.

It is also used as an active carrier, emulsifier, and mattifier due to its ability to absorb excess oil.

In some products, tiny microneedles called spicules are made from silica or hydrolyzed sponge. When you rub them in, they lightly polish away dead skin layers and enhance the penetration of active ingredients.

You might see people debate whether Sodium Chloride is comedogenic, but there actually haven't been any comedogenic tests done on it. Either way, the overall formulation of a product matters a lot more than any single ingredient.

You might see this ingredient used in scrubs as a primary exfoliating ingredient.

You'll most likely see it paired with steareth-2 because the two work together to create stable formulations.

1,4-dioxane is often brought up as a concern but this is usually removed through purification.

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.

On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.

One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too strong if you have sensitive skin).

Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.

You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.

Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.

It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.

Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.

We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.

Some people may experience allergies from this dye, especially asthmatics and those with an aspirin intolerance.

This ingredient can be found in makeup, sun care, and skincare.