Hsgn 1% Bakuchiol & Aquaporin Activator Eye Cream

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.

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.

Some foods that contain glyceryl glucoside include sake, miso, and wines.

In vitro research found an increase in skin hydration by 58% and a decrease in TEWL by 37.8% after 24 hours of applying this ingredient (pretty impressive for a single ingredient!).

Besides hydration, shea butter also contains triterpenes that have anti-inflammatory potential. In particule, lupeol cinnamate has shown the highest anti-inflammatory activity in vivo.

Shea butter also contains vitamins A and E which may contribute to antioxidant activity.

While Shea Butter has an SPF rating of about 3-4, it is not a sunscreen replacement.

This ingredient may not be fungal acne safe because its fatty acids fall within the C11-C24 range that the Malassezia yeast can metabolize.

You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.

In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.

If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.

When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.

When you apply niacinamide to your skin, your body converts it into nicotinamide adenine dinucleotide (NAD). NAD is an essential coenzyme that is already found in your cells as "fuel" and powers countless biological processes.

In your skin, NAD helps repair cell damage, produce new healthy cells, support collagen production, strengthen the skin barrier, and fight environmental stressors (like UV and pollution).

Our natural NAD levels start to decline with age, leading to slower skin repair, visible aging, and a weaker skin barrier. By providing your skin niacinamide, you're recharging your skin's NAD levels. This leads to stronger, healthier, and younger looking skin.

Another name for vitamin B3 is nicotinamide. This vitamin is water-soluble and our bodies don't store it. We obtain Vitamin B3 from either food or skincare. Meat, fish, wheat, yeast, and leafy greens contain vitamin B3.

The type of niacinamide used in skincare is synthetically created.

1) produce more collagen (type I, III, and IV)
2) activate the same genes retinoids do

Unlike retinoids, this ingredient will not increase photosensitivity and is safe to use during pregnancy (but please still check in with your doctor!).

The flagship clinical trial from Dhaliwal et al. 2019 found 0.5% bakuchiol (twice daily) and 0.5% retinol (once daily) reduced wrinkles and hyperpigmentation equally, but bakuchiol had significantly less irritation.

Systematic reviews also back this up:

Bakuchiol is comparable to retinol for photoaging but with better tolerability. It also has mild antibacterial properties against Cutibacterium acnes and antifungal activity in vitro against Candida and dermatophytes.

The reason bakuchiol works well is due to its structure; it is a meroterpene phenol, or a hybrid molecule. The phenol half acts as an antioxidant while the terpene half is fat-loving. This helps the molecule slip through the skin barrier.

This ingredient is usually used between 0.5-2%. Only one case of contact dermatitis has ever been reported for this ingredient.

This is due to how structurally similar it is to what your skin already produces.

Though it is mostly an emollient that helps soften and hydrate skin, it also has some humectant and occlusive action. Humectants help the skin retain moisture while occlusives seal it in, making squalane a triple-threat moisturizer.

Research shows it has antioxidant capabilities that help protect against stressors like UV exposure, specifically UVA induced oxidative stress. This study also found that it supports collagen biosynthesis in human dermal fibroblasts.

No clinical study has reported significant adverse effects and irritation reactions are very rare from this ingredient (even at 100% concentration).

Overall, it's a fantastic ingredient for hydration and is suitable for all skin types.

This depends on the source. Squalane can be derived from both plants and animals. Most squalane used in skincare comes from plants.

Please note: the source of squalane is only known if disclosed by the brand. We recommend reaching out to the brand if you have any questions about their squalane.

Read more about squalene with an "e".

Though squalane is often called an oil, it’s technically not one. It is a hydrocarbon, meaning it is only made of carbon and hydrogen. True oils are triglycerides and made of fatty acids and glycerol.

The term “oil-free” isn’t regulated so companies can define it however they want. Some exclude all oils, while others just avoid mineral oil or comedogenic oils.

Squalane has a comedogenic rating of 1 from the original 1972 study that tested raw ingredients under occlusion on rabbit ears. This system is not standardized or peer-reviewed, and using the raw ingredients is very different from how diluted cosmetic formulations are used on human skin.

A comedogenic rating of 1 means it is "unlikely to clog pores" according to the original rating system.

The overall formula of a product matters more than the individual ingredients on whether or not it will cause clogged pores.

This ingredient is an emollient, emulsifier, and penetration enhancer. As an emollient, it helps soften and hydrate skin by trapping moisture within. As an emulsifier, it prevents oil and water ingredients from separating.

Hydrogenated Lecithin can form tiny spherical structures made of phospholipid bilayers called liposomes. These liposomes are able to capture compounds inside their structure and deliver them through the skin barrier.

Because phospholipids are a natural component of our cell membranes, this ingredient is inherently compatible with skin.

A 2021 study found lecithin-based surfactants were less harsh and more tolerable comared to Sodium Lauryl Sulfate (SLS).

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.

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.

These "skin-like" liquid crystals improve skin barrier integrity and promote the delivery of actives into the skin.

This ingredient is well-tolerated and has no significant sensitization data.

Because it is derived from the fatty acids in olive oil, this ingredient may not be fungal acne safe.

This ingredient is also known as part of Olivem 1000, with Cetearyl Olivate being the other part.

According to a manufacturer, this ingredient helps preserve the natural microbiome of skin. Having a healthy microbiome helps keep our skin healthy and protects against harmful bacteria.

Please note, having a healthy microbiome is different from fungal acne; a healthy microbiome includes small amounts of yeast that normally live on your skin without causing problems.

Fungal acne happens when one type of yeast (Malassezia) grows out of control. This is usually because it's feeding on certain oils or fatty acids. Due to the olive oil base, this ingredient may not be fungal acne safe.

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.

This ingredient may not be fungal acne safe. It is a primary fatty alcohol with a chain length above 12 carbons. A study from 2019 show Malassezia can feed on fatty alcohols in this range, so it may trigger fungal acne in those prone to it.

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.

Some studies suggest betaine may support making skin tone more even.

Fun fact: Betaine naturally exists in the skin and the body. In cosmetic products, it can be either plant-derived (most commonly from sugar beets) or synthetically produced for consistency and stability.

Betaine is also known as trimethylglycine.

Glycation is the process of sugars binding to and damaging proteins. Too much sugar in our skin can lead to damaged collagen, contributing to factors of aging.

Carnosine is water-soluble and is not able to travel deeper layers of skin. This leads to some doubt about whether it can boost collagen in skin, since collagen is located in the deeper layers of skin.

Fun fact: Carnosine can be naturally found in our muscles and brain.

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.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

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.

In a 24 hour occlusive patch test on 56 subjects, 10% sorbitan isostearate was completely non-irritating. Most formulas use less than 10%.

Because it's a fatty acid ester, it may not be fungal acne safe since the Malassezia yeast can utilize it as a nutrient source.

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.

Your skin has cells called fibroblasts that build collagen (the stuff that keeps skin firm and smooth). Adenosine basically flips a switch on these cells that tells them to get to work making more collagen and other proteins. These cells slow down on their own as skin ages, so Adenosine helps give them a little nudge to keep going.

The clinical backing is pretty solid too.

A blind, randomized, placebo-controlled trial of 126 women aged 45-65 tested a 0.1% cream twice daily and found real improvements in crow's feet and frown lines using a precise 3D skin-mapping technique; these changes showed up by week 3 and held at 2 months.

A later study using Adenosine-loaded dissolving microneedle patches reported gains in wrinkle depth, dermal density, elasticity, and hydration.

On concentrations, South Korea's Ministry of Food and Drug Safety has set 0.04% as the approved functional anti-wrinkle level. You'll typically see this ingredient used somewhere in the 0.04-0.1% range since it works at low doses.

This ingredient has been found safe for cosmetics with the data showing no irritation or sensitization.

Overall, this is a great ingredient for any anti-aging routine and has no photosensitizing effect, so it suits both AM and PM use.

Beyond anti-aging, resveratrol is also valued for its skin-brightening and soothing properties.

Some forms of resveratrol appear to be more effective than others. Resveratrol isobutyrate and resveratrol butyrate are often cited as more stable derivatives.

Research also suggests these two forms have stronger effects on Type I collagen stimulation and inflammation reduction compared to basic resveratrol.

Resveratrol is naturally unstable and can degrade when exposed to light and oxygen. Well-designed products often use stabilized derivatives, airless or opaque packaging, and supporting antioxidants to help maintain effectiveness on skin.

A note on resveratrol as a retinoid alternative:
While resveratrol offers antioxidant protection, inflammation control, and some collagen-supporting benefits, it does not replace retinoids in terms of cell turnover or acne treatment.

However, it can be a useful option for people with retinoid sensitivity or intolerance, or for those looking to support skin health without irritation.

Fun fact: Resveratrol is naturally found in grapes, peanuts, and berries, which is why it’s frequently associated with wine and grape-derived skincare ingredients.

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.

On the surface, it acts as a humectant that holds water in place and reduces moisture loss for a plumper, smoother feel, while its anti-inflammatory and antioxidant properties make it a great pick for calming redness or sensitive skin

The more interesting story is underneath:

Despite its large molecular size, oat beta-glucan has been shown to penetrate the epidermis and reach the dermis by slipping between skin cells. Here, it interacts with fibroblasts and macrophages to nudge collagen synthesis and support wound repair.

A small 2005 split-face clinical study of 27 subjects found topical beta-glucan produced measurable reductions in wrinkle depth, height, and roughness after 8 weeks of use.

It is worth noting the trial was small and the penetration testing used frozen, irradiated skin so the anti-aging data is encouraging rather than definitive.

This ingredient gets along with pretty much everything and is typically used around 0.1-1%.

Fungal acne: This ingredient is not a food source for the Malassezia yeast because it is a glucose polysaccharide with no fatty acid or ester component.

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%.

It plays well with most ingredients and is typically used at 0.1-1%. However, concentrations up to 50% have been reported in moisturizers.

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.

This ingredient offers promising benefits, but it is relatively new and more evidence is needed to prove its efficacy. The manufacturer claims this ingredient:

A study from 2022 found this ingredient helped protect skin against damaged from UV exposure (though this should not replace your sunscreen!).

The lysate in the ingredient name refers to a fluid that forms from breaking down the cell membrane.

Foods rich in riboflavin include eggs, milk, organ meat, cheese, and yogurt.

Learn more about other types of Vitamin B:

A 2023 review noted that probiotic fermentation ingredients like this one can enhance antioxidant capacity, reduce UV-induced oxidative damage, and support barrier function.

One clinical study from the same year showed a Lactobacillus ferment lysate significantly reduced transepidermal water loss and improved skin hydration.

Another review highlighted that topical Lactobacillus-based preparations can improve ceramide levels in the stratum corneum, support barrier integrity, and even help reduce S. aureus colonization in atopic dermatitis.

Why is this so cool?

Basically, your skin's outer layer works as a brick wall; skin cells are bricks and ceramides are the mortar holding it together. Moisture escapes, irritants get in, and your skin gets dry and reactive when ceramide levels drop. On top of that, "bad" skin bacteria S. aureus loves to move in when your barrier is weak to make inflammation and irritation worse.

So Lactobacillus ferment is basically patching the wall and evicting the troublemaker when it boosts ceramide production and help keep S. aureus in check.

On top of all this, it also acts as a mild antimicrobial preservative booster.

Just so you know, most studies focus on specific strains or the lysate form rather than this generic "Lactobacillus Ferment", so results can vary.

Though it's a promising ingredient, it doesn't have decades of robust clinical data behind it just yet.

Lactobacillus Ferment is generally considered safe for fungal-acne prone skin. The key thing to understand is that it comes from bacteria, not yeast or fungus.

Yeast-derived ferments (like galactomyces) have been shown to activate a protein that's linked to Malassezia-related skin issues whereas lactobacillus doesn't have that problem.

Its byproducts also don't contain the types of fatty acids (C11-24 chain lengths) that Malassezia feeds on.

Studies show this ingredient can help calm redness and may help treat the signs of photoaging; however, the evidence is inconclusive and further studies are needed.

Lactobacillus Ferment is generally considered safe for fungal-acne prone skin. The key thing to understand is that it comes from bacteria, not yeast or fungus.

Yeast-derived ferments (like galactomyces) have been shown to activate a protein that's linked to Malassezia-related skin issues whereas lactobacillus doesn't have that problem.

Its byproducts also don't contain the types of fatty acids (C11-24 chain lengths) that Malassezia feeds on.

This ingredient has antimicrobial properties and helps prevent the growth of bacteria in a product.

Leuconostoc is used to make the traditional Korean side-dish, kimchi. It is also used to make sourdough bread (both incredibly yummy foods).

This ingredient is generally considered fungal acne (Malassezia) safe; Bifidobacterium is a bacterium, not a yeast or fungus.

The fungal acne concern with fermented ingredients mainly applies to yeast-derived ferments like Saccharomyces and Galactomyces, because those are in the same kingdom as Malassezia and could theoretically contain residual compounds that feed it.

Bifida is a completely different organism, so on its own it doesn't provide a food source for the Malassezia yeast that causes fungal acne.

This ceramide works by slotting into gaps within the stratum corneum's lipid matrix to limit trans-epidermal water loss (TEWL) and shield the skin against external irritants.

A study with 312 patients found that using a ceramide-containing routine for 4 weeks reduced the severity of atopic dermatitis by over 61%.

Another clinical study in subjects aged 60 and older found that a ceramide body wash and moisturizer improved skin dryness and itchy skin in 15 days.

Overall, ceramides are considered non-irritating and safety tests have found little to no observable adverse effects from using this ingredient.

Ceramide NP is usually sourced from plants (like soybean or rice bran), or produced synthetically.

Research shows it can encourage your skin cells to turn over and renew by stimulating keratinocyte and fibroblast proliferation.

It also has mild keratolytic properties to help loosen and shed dead skin cells without being harsh.

Studies also suggest allantoin can help calm inflammation by dialing down some of the chemical signals your skin sends out when it is irritated.

This ingredient is typically used in the 0.1-0.5% range, and the FDA recognizes it as a skin protectant in OTC products up to 2%.

Overall, allantoin is a wonderful addition to most routines; it is stable across a wide pH range (~4-8), works well with other ingredients, and is considered non-sensitizing/non-irritating.

Fun fact: Allantoin is naturally occurring in comfrey root, beets, chamomile, and wheat sprouts. Our bodies even produce it as a byproduct of uric acid metabolism.

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.

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.

Research on a hydrogel with serine confirmed this serine got delivered to your stratum corneum and demonstrated enhanced skin moisturization.

Interestingly serine also helps your skin produce filaggrin, a protein that keeps your skin barrier strong and used to create collagen.

An in-vitro study from 2024 found glutamic acid to play a role in inhibiting inflammation and thus a potential skin-soothing ingredient.

Other studies show it to be have potential wound healing, skin barrier repair, and hair growth properties.

Glutamic acid has poor solubility in water and other solvents.

Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces.

A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks.

Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.

One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.

Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne.

Reviews of this ingredient have found it to be neither a dermal irritant nor a sensitizer.

Fun fact: Proline can be found in protein-rich foods like meat, fish, eggs, and dairy.

As a cosmetic ingredient, it grabs water and holds it in the upper layers of skin to smooth roughness and ease dehydration.

There's some clinical support for the NMF approach with a study showing that a cream built to mimic the skin's NMF significantly boosted hydration.

Safety-wise, this ingredient non-irritating, non-comedogenic, and non-phototoxic in testing, with minimal skin absorption.

It also works really well with other hydrators like glycerin or hyaluronic acid, and typical usage is somewhere between 0.2-4%.

As a humectant, Sorbitol helps draw water to the skin. This helps keep the skin hydrated. Sorbitol also helps create a thicker texture in products. You might find sorbitol in your toothpaste and other gels.

It is a non-irritating ingredient that is great for those with dry skin.

Sorbitol is a prebiotic. It helps promote the growth of healthy bacteria on your skin. The bacteria on your skin form a microbiome. This microbiome helps protect your skin from infection and harmful bacteria.

In skincare, lysine is mostly there to help keep your skin moisturized. It carries water through your skin's layers so everything stays plump.

So will putting lysine on your face create bouncier skin?

It's hard to say; most of the exciting collagen research on lysine comes from oral supplements or lab studies on mice. Further research is needed to truly understand what role topical lysine plays in skincare and your skin.

However, there's no harm in adding lysine to your routine as a supportive and hydrating ingredient.

In skincare, it's mainly used as a skin conditioning ingredient that helps reinforce the same moisture-retention function.

You'll usually see it used at low percentages (generally under 5%) which is in line with how amino acids are used in cosmetics.

One manufacturer study found their glycolipid also demonstrated sebum reduction and helped reduced oiliness after four weeks. This means it can also be great for scalp care.

Fungal acne note:
Since this ingredient is made from oleic acid, it might not be fungal acne safe. The Malassezia yeast survives by eating certain fats, including oleic acid.

However, it should be noted this oleic acid is chemically bound to a large polyglycerol molecule, so it might not trigger fungal acne for everyone.

Beyond hydration, Biosaccharide Gum-1 gives formulas a silky, non-sticky feel.

This ingredient is gentle, versatile, and suitable for all skin types.

Fun fact: Similar sugars can be found naturally in fruits like apples and pears.

However, the tanning claim is shaky. Lab studies on isolated skin cells show tyrosine can boost melanin production at fairly high concentrations but hasn't shown to speed up/deepen a tan when applied directly to skin in animal studies (up to 0.05%).

Finished cosmetic products use it at low levels (generally well under 1%). At these amounts, it's considered non-irritating and non-sensitizing based on repeat-use patch testing.

Allergy-wise, plain tyrosinase hasn't shown sensitization issues but a chemically modified relative called Oleoyl Tyrosine has had a handful of cases.

Two structures of phenylalanine exist: L-phenylalanine and D-phenylalanine. L-phenylalanine is essential, this means our bodies cannot produce it naturally and we must get it from foods. Our bodies convert D-phenylalanine to neurotransmitters, and D-phenylalanine is found in our bodies naturally.

Some foods that contain L-phenylalanine include eggs, soybeans, beef, milk.

It's one of the small building blocks that make up your skin's natural moisturizing factor (NMF), or the built-in system that helps skin hold onto water. So its main job in a formula is to give the skin gentle hydration and help it feel more comfortable.

Typical amounts are very tiny: roughly 0.00004%-0.5% in leave on products and up to 1% in rinse-off ones.

The Cosmetic Ingredient Review panel has looked at this ingredient and found no evidence of it being a skin irritant or allergen at cosmetic levels.

One study found histidine and carnosine to be a dynamic duo for your skin:

Oral histidine has also been found to help with filaggrin-deficit skin disorders such as atopic dermatitis.

Why is it considered a semi-essential amino acid? This is because adults are able to create it but children must get it from their diet.

Usage percentages are usually under 1%, and usually as part of an amino acid mix designed to mimic what's naturally in skin.

One study used a combination of essential amino acids at 0.2% with supplemental methionine added and found significantly boosted collagen production in human skin.

Cosmetic industry reviewers have looked closely at methionine and other amino acids and found them well tolerated. Methionine is actually used as a "negative control" in lab tests designed to spot irritating ingredients because it doesn't cause a reaction.

Typical use concentrations for this ingredient are usually quite low (under 5% in leave-on skincare).

Safety data on cysteine specifically shows it's not a skin or eye irritant.

In skincare, it's best known as a brightening ingredient that slows down tyrosinase, the key enzyme that makes skin pigment. It also nudges the skin toward making a lighter type of pigment instead of a darker one.

This is why you'll see it in products aimed at dark spots and uneven tone.

A small number of real human trials have found a topical glutathione lotion:

The honest caveat is that the current evidence is still thin (few studies, small groups, short timelines). Glutathione also doesn't absorb into skin very easily so results tend to be modest and fade if you stop using it.

One thing worth clearing up:

The scary side effects you may have heard about come from glutathione injected intravenously, which has real safety concerns. Applying it topically is a completely different thing and has a clean track record.

Most human studies used it around 2% (as Glutathione or Glutathione Disulfide) and a 2% oxidized glutathione lotion and a 2% S-acyl glutathione cream are the concentrations with actual clinical data behind them.

There's no established "ideal" percentage yet but 1-2% is the evidence-backed range.

Allergy-wise, there is very low risk for this ingredient; it was well-tolerated across the topical trials. Only one participant had mild temporary redness that cleared up on its own and another study reported no adverse reactions at all.

One trial had ~10% of users drop out for irritation was using a combination cream that also had 10% azelaic acid so the irritation likely wasn't from the glutathione. There's no notable contact-allergy signal for topical glutathione in the literature but patch-testing before first use is still sensible for those with sensitive skin.

The good news is: studies show applying this ingredient topically replenishes ubiquinone levels in our skin. This also comes with a ton of skin benefits. These benefits include:

Ubiquinone is considered a large molecule and cannot be absorbed into the lower layers of skin. This is why it is believed to be such an effective antioxidant: it protects our skin in the upper layers and prevents damage in the deeper layers.

When used in sunscreen, ubiquinone is shown to increase ingredient stability, increase SPF factor, and add to infrared protection.

Fun fact: ubiquinone is fat-soluble.

According to studies, low molecular-weight hyaluronic acid can:

One study from 2011 found ultra-low weight HA to show pro-inflammatory properties. Another study from 2022 found it to downregulate UV-B induced inflammation.

Hydrolysis is a process of changing a molecule using water or enzymes.

This ingredient is water-soluble.

Regular hyaluronic acid carries a negative charge and so does the surface of your skin. This means the two repel each other and hyaluronic acid can be washed away easily. The positive charge here does the opposite: it makes the ingredient cling to your skin (also called "substantivity") so it keeps hydrating even in rinse-off products where it lays down a light, moisture-holding film.

The research backs this up too; a 2025 clinical study on a shower gel containing 0.1% positively charged hyaluronic acid increased skin hydration by 6.6% versus the baseline and 11.1% versus the placebo. This was measured 6 hours after 1 minute of contact and rinse, and on volunteers with very dry skin.

The same team's lab work showed it adhered to skin far better than unmodified hyaluronic acid (+107% vs. low molecular weight, +23% versus high molecular weight). They also found it increased two proteins tied to skin hydration, aquaporin-3 by 16% and filaggrin by 35%.

A separate 2024 study reached a similar conclusion and credited the hydrating benefits to its film-forming properties.

Both studies used the ingredient at 0.1% which also matches how much it usually shows up in products (at fractions of a percent).

One honesty note worth keeping in mind: the published research comes from the company that manufactures the ingredient so independent data would strengthen the picture. However, the results are consistent and the mechanism makes sense.

As a Hyaluronic Acid derivative, it has a well-tolerated profile and suits most skin types.

Read about common types of Hyaluronic Acid here:

Because hydrolyzed hyaluronic acid is smaller in size, it can slip past your outermost layer of skin more easily than full-sized HA.

Most formulations will combine all sizes to get the best of both worlds.

Typical usage levels range from 0.01-1%. Any percentage higher than 2% might become goopy and tacky.

Emerging studies show Nonapeptide-1 to help with reducing pigmentation and brightening the skin. It has shown to prevent the activation of tyrosinase, an enzyme in the skin that begins the process of melanin creation. Melanin is responsible for giving skin a tan or dark spots.

While this seems promising, research is lacking in proving this ingredient to be as effective as botox.

Notably, this ingredient is oxidatively stable for an oil and resists going rancid as fast as other oils.

A small, in vivo study on 32 participants found a cream with this ingredient increased skin hydration with no reported skin irritation. It also found the tocopherol content gave it some antioxidant activity as well.

One thing to flag for fungal acne:
Because this oil is so high in oleic acid, Malassezia can use it as a food source and this ingredient may not be fungal acne safe.

For everyone else, this ingredient is well-tolerated and nourishing with a good safety track record.

First, Retinyl Palmitate is created from Palmitic Acid and Retinol. It is a Retinol ester and considered one of the weaker forms of retinoid.

This is because all retinoids have to be converted to Tretinoin, AKA Retinoic Acid.

Retinyl Palmitate is pretty far down the line and has to go through multiple conversions before its effects are seen. Once it's on your skin, enzymes called esterases convert it into Retinol, then into Retinal, and finally into Retinoic Acid; that's three steps with a little lost at each one.

The benefits of Retinyl Palmitate are debated due to this long and ineffective conversion line.

So why use it at all?

The answer is stability. Retinol and Retinoic Acid break down fast when they hit light, heat, and air, and Retinoic Acid can be pretty irritating on top of that.

Retinyl Palmitate is much more stable and gentler, making it easier to formulate with and easier on sensitive skin (even if it's weaker gram for gram).

Studies show Retinyl Palmitate to help:

Newer research from 2023-2025 also found that Retinyl Palmitate works especially well when paired with Retinol. The two seem to cover each other's weak spots; retinol brings the potency while Retinyl Palmitate brings the stability and gentleness. Together, they repair UV damage better than either one does alone.

This ingredient used to be found in sunscreens to boost the efficacy of sunscreen filters.

The downfall of Retinyl Palmitate was due to released reports about the ingredient being correlated to sun damage and skin tumors.

Most of this traces back to a 2012 US National Toxicology Program (NTP) study where hairless mice coated in Retinyl Palmitate cream and exposed to UV light developed skin tumors faster.

Here's the nuance, though.

When the Cosmetic Ingredient Review (CIR) Expert Panel went back through that study, they found methodological flaws and decided the results couldn't be interpreted as proof of extra risk.

The EU's Scientific Committee on Consumer Safety (SCCS) said the mouse findings might point to a concern but they're hard to apply to humans since hairless mouse skin and human skin behave differently.

While there is a study showing this ingredient to cause DNA damage when exposed to UVA, there is no concrete proof of it being linked to skin cancer. It is completely safe to use when used correctly.

Both the CIR and the SCCS consider it safe at the concentrations used in cosmetics; the SCCS specifically cleared retinoids up to 0.05% in body lotions and 0.3% in face creams, hand creams, and rinse-off products.

As of 2025, the EU has written those limits into law, plus a label warning about your total Vitamin A intake from all sources.

All retinoids increase your skin's sensitivity to the sun in the first few months of usage. Be especially careful with reapplying sunscreen when using any form of retinoid.

One more note: if you're pregnant, high doses of Vitamin A can be a concern, so a lot of people skip topical retinoids (including Retinyl Palmitate) during pregnancy just to be safe. Check with your doctor if you're unsure.

Fun fact: This ingredient is often added to low-fat milk to increase the levels of Vitamin A.

While MAP is gentler on the skin than ascorbic acid, it is thought to be less easily absorbed into the skin.

In a well-known absorption study, pure vitamin C increased skin vitamin C levels when formulated correctly, but derivatives like MAP did not in that experiment. This suggests MAP may not always convert into active vitamin C in the skin.

Due to MAP's stability up to a pH level of 7, it is more stable to air and sunlight exposure than ascorbic acid. The best pH range for MAP is between 5 and 6.

More research is needed on applying biotin topically. However, taking biotin orally has been shown to help nourish the skin, hair, and nails. They play a role in forming skin-hydrating fatty acids.

Biotin is water-soluble. It can be found in foods such as fish, eggs, dairy, nuts, and meat. Vitamin H stands for "haar" and "haut". These are the German words for hair and skin.

The reason this ingredient is so effective is because it forms a thin film on the skin that reduces transepidermal water loss (TEWL) while supplying linoleic acid to the stratum corneum to improve barrier strength.

The high linoleic acid content is particularly noteworthy for acne-prone skin.

Research suggests that acne-prone skin tends to be deficient in linoleic acid in sebum. Topical application may help replenish this to support a healthier follicular environment and less comedone-promoting sebum.

One randomized study found sunflower seed oil preserved skin barrier integrity in adult volunteers with and without atopic dermatitis (outperforming olive oil).

This ingredient is well-studied, gentle, and an effective emollient suitable for most skin types.

On fungal acne: This ingredient may not be Fungal acne (Malassezia folliculitis) safe. This is because it contains fatty acids with carbon chain lengths in the C11-C24 range.

Unlike the extract, this ingredient only carries trace amounts of catechins, amino acids, and caffeine that makes tea leaf extract famous.

Polyacrylate-13 is a copolymer of acrylic acid, acrylamide, sodium acrylate, sodium acryloyldimethyltaurate monomers

Methylpropanediol is able to add a bit of moisture to the skin. It also helps other ingredients be better absorbed into the skin, such as salicylic acid.

Studies show SAP has anti-acne and antioxidant benefits. One study found 5% of SAP lotion to be an effective ingredient for treating acne vulgaris. This is because research shows that SAP may help control acne by reducing acne-causing bacteria and slowing the oxidation of skin oils caused by UV exposure.

In addition to acne, vitamin C is important for skin structure. Lab studies suggest SAP may support collagen production in skin cells, making it a great ingredient in anti-aging routines.

Vitamin C has many benefits: it helps reduce redness, improve skin texture, fade the appearance of dark spots, and brighten the skin.

Read more about other types of Vitamin C:

A follow-up clinical trial found that a topical crosslinked HA serum applied after fillers, microneedling, or chemical peels was well-tolerated and enhanced skin quality at 14 / 28 days.

More recent research suggests that concentrations as low as 0.03% can act as a penetration enhancer for other skincare actives.

It’s considered a “next-gen” version of Argireline (Acetyl Hexapeptide-8), an older peptide with more research behind it that also supports collagen production.

SNAP-8 showed slightly better results than Argireline in one small manufacturer-funded study, but there’s limited independent research. Plus, most tests use concentrations higher than what’s typically found in skincare products.

This ingredient might offer a subtle smoothing effect but it won't don’t deliver the dramatic results of actual Botox injections.

Think of it more like a supporting actor in your skincare lineup.

In this case, the 60 comes from reacting 60 units of ethylene oxide with sorbitan.

Polysorbates are commonly used in medicine and foods.

According to the manufacturer, this peptide boosts the skin's immune defenses and regenerates the outer layers of skin.

The manufacturer has found combining this ingredient with red clover extract (Capixyl) boosted benefits. Not only does it enforce the scalp's extracellular matrix, it also inhibits the enzyme that creates DHT, a hormone that leads to hair loss.

While this ingredient is promising, more research is still needed to confirm its full effectiveness.

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:

An in-vivo study from the manufacturer found 95% of volunteers saw eye bag improvement by the end of the study.

Eye puffiness is caused by two major factors: fluid retention and fat.

Those with fluid retention may see improvement from using this ingredient. However, those with eye fat will need surgical intervention in order to get rid of puffiness.

The comparison to Botox does have limits because the molecule is water-loving and relatively large.

Acetyl Hexapeptide-8 has a hard time absorbing deeply enough through the skin's outer barrier to actually reach the muscles.

So whether it truly works the way Botox does at a biological level is still up for debate, but early clinical outcomes are fairly encouraging.

A 12 week human study of a multi-ingredient regimen containing this ingredient saw:

While some studies have observed improvements in wrinkle appearance, it is important to note that more consistent results are seen in multi-ingredient formulations (vs just Acetyl Hexapeptide-8 alone).

Some research studies also used higher concentrations (up to 10%) while this ingredient is usually found in concentrations up to 0.005% in leave-on formulations.

Its soothing ability comes from a variety of compounds including biflavones, a type of flavonoid. Studies show gingko biloba has strong anti-inflammatory properties.

Fun fact: This tree is native to China and has been used in traditional Chinese medicine for thousands of years.

UV-exposed skin cells treated with EGCG showed less of the enzyme that chews up collagen, lower inflammatory signaling, and better preserved barrier function.

EGCG nudges skin cells to make more of your skin's built in moisturizing molecules, filaggrin and hyaluronic acid, for better skin hydration.

Because it inhibits melanogenesis, it also provides a mild brightening effect.

Clinically, topical EGCG has helped calm radiation-related skin irritation and scalp seborrheic dermatitis with no major side effects.

In an 8-week split-face study, topical EGCG at 1% and 5% significantly reduced inflammatory and non-inflammatory acne.

A study from 2023 on patients with Seborrhea (a chronic skin condition caused by overactive sebaceous glands) found that using a 5% EGCG cream (alone and combined with 2% L-carnitine) and found meaningful sebum reduction plus better hydration.

Just one caveat here: Most clinical trials used 1-5% concentrations and most cosmetics contain only 0.1-1%.

The only headache related to this ingredient is stability. EGCG degrades quickly with heat, light, oxygen, and higher pH.

That's why you'll usually see it in low-pH formulas (4.5-6.5) or paired with vitamin C + vitamin E to slow its degradation. Hyaluronic acid also stabilizes it and boosts its antioxidant activity.

While studying wound healing, researchers noticed GHK-Cu stimulated hair follicle enlargement and growth by keeping hair in its active growth phase longer. This has made it a promising ingredient for hair regrowth treatments.

Some people have reported increased facial hair. While GHK-Cu can make your hair follicles bigger, it usually doesn’t turn soft, barely-visible facial hairs into thick, dark ones.

Anecdotal reports suggest that overusing copper peptides might lead to premature aging due to excess free copper or enzyme imbalances. This claim isn’t backed by large-scale studies.

Unfortunately, there are limited human studies for this ingredient. While early results are promising, many studies are either small, in-vitro, or not rigorously controlled.

For example, there is a 1998 study that explored the effects of copper tripeptide, vitamin C, tretinoin, and melatonin on skin repair and collagen synthesis.

After one month, increased procollagen production was seen in 7 out of 10 participants using copper tripeptide (more than those using vitamin C, melatonin, or tretinoin.

While the study was exploratory, it offers early evidence that copper tripeptide may support collagen production. Larger, well-designed trials are still needed to confirm its potential and understand individual responses.

Read more about other common types of peptides here:

It's actually inactive on its own and works like a slow-release "storage" form; the enzymes in your skin called esterases gradually convert it into active vitamin E over time.

One in vivo study showed 5% of the acetate in the living layer of the epidermis converted to vitamin E after 5 days of application. This study also found the skin gained protection against UV damage even though the conversion was slow and small.

Once converted, vitamin E acts as a skin's main fat-soluble antioxidant that fights free radicals to protect skin from damage.

Topical vitamin E generally boosts the skin's photoprotection, and it reduced UV-damage in animal models.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

Overall, it has a pretty solid safety profile and has been found to be non-irritating and non-comedogenic. Allergic reactions may happen but stay rare due to how widely the ingredient gets used.

The concentration will vary depending on the formula; industry data shows 0.1% in baby lotions, 3% in lipsticks, and 5% in foot powders. You can also find this ingredient at 100% in a pure vitamin E oil.

Most leave-on skincare keeps it at the lower end, often between 0.5-1%.

GHK is also unique because is also acts as a carrier peptide. It binds to and transports copper ions (forming the complex GHK-Cu). This form has been studied for decades and is known to stimulate wound healing, boost antioxidant defenses, and promote collagen/elastin synthesis.

In-vitro studies show both GHK and GHK-CU increase fibroblast activity that enhances the production of collagen, elastin, fibronectin, and other extracellular matrix components.

Both of these compounds also help balance enzymes that control collagen breakdown.

Human studies (in-vivo) using GHK-Cu creams have reported visible improvements to skin density, elasticity, and wrinkle depth after several weeks of use.

A small clinical study also found topical collagen tripeptide improved wrinkle appearance and skin elasticity in women after four weeks.

While these results are promising, most research is based on GHK-Cu or its derivatives rather than Tripeptide-1 alone (Palmitoyl Tripeptide-1 is a famous derivative of GHK). However, the consensus still supports GHK as a potent skin-signaling molecule that can encourage regeneration and maintain youthful looking skin.

Fun fact: GHK is a naturally occurring fragment of type 1 collagen that can be found in human plasma, saliva, and urine.

Learn more about Vitamin B in skincare:

The bioactives in the root extract have also been shown in lab tests to have anti-wrinkle, antioxidant, and anti-allergy properties.

A big 2022 review looked at the whole Dioscorea family and found these plants consistently showed antioxidant activity across the board.

This ingredient is gentle and well-tolerated by all skin types.

Last, the phytochemicals found in apples are strong antioxidants. These antioxidants help with anti-aging as they protect your skin cells against oxidative damage.

Some sources suggest this ingredient may cause skin sensitivity but further studies are needed.

These compounds allow centella to dial back inflammation, encourage the skin to build and hold onto collagen, support the barrier and hydration, and bring solid antioxidant activity to protect against signs of aging.

Centella also carries a nice supporting cast of Vitamin A, vitamin C, several B vitamins, and amino acids. Put it all together and you get an ingredient that soothes, hydrates, and protects, all at once.

Most of centella's magic comes from the four big compounds (Asiaticoside, Madecassoside, Asiatic Acid, and Madecassic Acid). These are the actives doing the heavy lifting in almost every centella study.

Here is the short version of what they do in the skin:

So it is not just soothing for the sake of soothing. Centella calms the skin AND helps it rebuild.

Just FYI, not all centella on an ingredient list is the same. What you are getting actually depends on the extract:

Fun fact on the ratios: the leaves tend to be richest in Madecassoside and Asiaticoside, and lower in the two acids. The exact amounts shift with where the plant is grown and how it is processed. This means purity really does vary brand to brand.

Centella is one of the most easygoing actives out there.

It layers well with basically everything: niacinamide, hyaluronic acid, peptides, and vitamin C, and also pairs nicely with stronger actives like retinoids and exfoliating acids where it can help take the edge off irritation.

On the safety side, centella and its triterpenes are classified as weak sensitizers, meaning allergic reactions are possible but uncommon.

Patch tests at 1% and 5% came back negative in test panels, and creams at typical use levels did not cause allergic reactions across large groups of people.

But as with any new active, a patch test is still a smart move for very reactive skin.

Centella is widely used because it is effective at low percentages. For context, human safety testing found no meaningful irritation from creams containing centella extract at everyday use levels (the tested amounts were well under 1%).

The irritancy threshold in animal testing was also above 30% (so real-world formulas sit far below anything concerning).

In collagen lab studies, higher concentrations drove more collagen synthesis, so serums built around centella tend to feature it more prominently.

Bottom line: you will find centella working nicely anywhere from a fraction of a percent up to hero-ingredient levels depending on whether it is a supporting soother or the main event.

Fun fact: Centella has been used as a medicine and in food for many centuries. As a medicine, it is used to treat burns, scratches, and wounds.

What you end up with is a water-loving ingredient packed with plant antioxidants and a gentle skin-dissolving enzyme that works in two ways:

1) it fights daily damage from things like pollution and UV
2) it lightly loosens dead skin cells on the surface for a smoother, brighter look.

The antioxidant side is the better studied half. Pomegranate's natural compounds help neutralize unstable molecules that damage skin cells and lab studies on skin cells show they can also help calm inflammation.

Exfoliation from this ingredient is soft; it gently loosens dead skin cells on the surface. Even manufacturers admit it's not as strong as AHAs like glycolic acid.

A 2022 human trial on a fermented pomegranate serum reported improvements in moisture, brightness, elasticity, spots, and collagen density after 4-8 weeks.

This ingredient is recommended to be used at 1-3% by suppliers. Since the Lactobacillus is a fermenting organism rather than live culture in a final product, there's no known fungal acne concern.

Just be sure to patch test or avoid if you have known pomegranate allergies.

The isoflavones are the workhorses behind the common claims; lab and animal studies show they mop up free radicals, help protect skin cells from UVB damage, and nudge fibroblasts to make more collagen while slowing the enzymes that break collagen down.

One controlled clinical study using an isoflavone cream reported softer wrinkles and better skin texture over time. A topical fermented soy extract also improved hydration and elasticity in an animal aging model.

The big caveat is that most of this evidence comes from soy isoflavones and related fermented soy extracts rather than this exact INCI. Some of the strongest data also comes from oral studies.

So it's best to think of this ingredient as a gentle, antioxidant-leaning conditioning agent rather than a proven wrinkle eraser.

At this time, there's no published concentration levels for this specific ferment but it usually shows up at modest levels in real products (~1% or less).

One last thing for people with soy allergies: it's always worth patch testing this ingredient despite the lowered allergy risk.

There's also some lab evidence that chia seed extract, when paired with pomegranate extract, may help reduce excess pigment production.

Curcumin also has anti-inflammatory properties and can help soothe skin and reduce irritation. On top of that, curcumin has been shown to help prevent hyperpigmentation from sun damage.

The anti-microbial property of turmeric can make it effective in treating acne. This property has also been shown to help regulate the production of sebum.

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).

This extract is created by using 50% 1,3-Butylene glycol.

Job's tears is rich in nutrients, such as thiamine, riboflavin, niacin and ascorbic acid.

You can also find great antioxidants such as ferulic acid, caffeic acid.

To top if off, ceramides are also present in this grain.

A study from 2002 found rice to help increase the rate of wound healing. The same study found an improvement of skin barrier function in the patients after taking rice baths.

Numerous in-vitro studies have found rice water to help decrease sun damage by increasing collagen production and inhibiting the process of tyrosinase.

Long story short- tyrosinase is an enzyme that controls melanin production. Our bodies start producing melanin (AKA tanning) when exposed to UV radiation to protect against damage. Rice water is found to partially block this process.

Though more research is needed on rice's ability to help with UV protection, recent studies seem promising.

Wondering why rice is hydrating? The protein in rice have emollient properties. Emollients create a barrier on the skin to trap moisture in, keeping your skin moisturized.

Some rice extract may have mildly-exfoliating properties. These are mainly limited to Oryza Sativa (Rice) Bran and Oryza Sativa (Rice) Germ Powder.

This rice was first cultivated in China over 10,000 years ago. Many cultures throughout Asia have used rice water on skin and hair for centuries.

Beta-carotene is the reason we turn orange if we eat too many carrots.

It should be noted coming into contact with the leaves of wild carrots can cause skin irritation. The sap causes phytophotodermatitis, or sensitivity exposed to sunlight.

This ingredient is created using the edible parts of the carrot.

There's also some interesting research on its potential to support hair growth by promoting the growth phase of the hair cycle.

Those with an allergy to plants in the daisy family may want to patch test this ingredient. This ingredient is generally well-tolerated otherwise.

A wound-healing study testing gels with the extract at 1%, 2%, and 3% concentrations and found none of them irritated the skin.

Most commercial products also use it in a similar low range (typically under 5%).

Allergy-wise, there are some case reports on neem oil causing allergic contact dermatitis so people with plant/botanical sensitivities may want to patch test first.

Some studies have explored oral supplementation of pantothenic acid in the acne context and found it to help reduce blemishes over time.

Though oral and topical use are different, this research helps explain why vitamin B5 is often included in skincare routines aimed at keeping skin balanced and hydrated.

This ingredient calms down a specific inflammation signal in your skin cells (called IL-6). When left unchecked, this signal triggers enzymes that break down collagen and elastin.

Clinical testing showed statistically significant improvements in:

Studies also found the more of this ingredient used, the more your skin produces Collagen I, fibronectin, and hyaluronic acid.

You'll likely see this ingredient paired with Palmitoyl Tripeptide-1 in the well-known Matrixyl 3000 complex for enhanced anti-aging effects.

A 3% concentration applied twice daily for two months showed meaningful skin rejuvenation results in clinical panels.

Fungal acne note:
Usually a palmitic acid component can feed Malassezia in unbound form, but here is is covalently bonded to the peptide. This means it is very difficult for Malassezia to access, and therefore very unlikely to cause fungal acne.

Once there, it acts as a matrikine, a signaling peptide that prompts fibroblasts to produce more collagen, fibronectin, and hyaluronic acid.

In vitro studies show it can boost collagen production in skin cells even when UV-damaged skin samples were treated with it at a tiny concentration (it almost fully restored dermal collagen at 5ppm). It achieved this at 100x lower concentration than retinoic acid, which needed 500 ppm to do the same thing.

Human clinical data is promising, but modest:

A study of 23 female volunteers found a small but statistically significant increase (~4%) in skin thickness after treatment at 4 ppm.

A separate small trial of 15 women showed statistically significant reductions in wrinkle length, depth, and skin roughness after applying it twice daily for four weeks.

You'll likely see Pal-GHK paired with Palmitoyl Tetrapeptide-7 as part of the Matrixyl 3000 complex.

Fungal acne note:
Usually a palmitic acid component can feed Malassezia in unbound form, but here is is covalently bonded to the peptide. This means it is very difficult for Malassezia to access, and therefore very unlikely to cause fungal acne.

It's designed to mimic the collagen-stimulating activity in your skin by copying a snippet of one of your skin's own matrix proteins. This nudges fibroblasts into making more collagen while inhibiting the enzyme that breaks down skin protein.

The manufacturer's in vivo study of 45 volunteers found 1% and 2.5% reduced the appearance of wrinkles by 7% and 12% respectively, after using it twice daily for 84 days.

This is in the expected range for peptides; they're slow and cumulative actives and not overnight fixers.

Typical use levels range from 1-3% and this ingredient gets along with pretty much everything.

On the fungal acne front:
Although palmitic acid sits in the chain length that Malassezia can feed on, this ingredient has it locked in an amine bond. This makes it hard for Malassezia to access as a source of food, and therefore fungal acne safe.

A 12 week clinical study found that a moisturizer containing just 3 ppm of Matrixyl led to a significant improvement in fine-lines and wrinkles. Another study showed an 18% reduction in wrinkle depth, 37% reduction in wrinkle thickness, and a 21% improvement in skin firmness after just 28 days of twice-daily use.

The coolest part is that it works at incredibly low concentrations (like 0.0003%) and it plays well with other actives.

The CIR (Cosmetic Ingredient Review) panel found it to be non-sensitizing across multiple tests and human patch tests also showed no irritation or sensitization.

Fun fact: Matrixyl was originally developed by French company Sederma and Procter & Gamble.

Read more about other common types of peptides here:

Another study using a cream with horsetail and soybean extract found 80% of participants showed at least a 26% improvement in forehead wrinkles after 8 weeks.

Animal research has shown topical Equisetum Arvense stimulated skin and tissue growth in mice.

The research so far is encouraging, but still in its early days. But it's a lovely supporting ingredient and can be a welcome addition to any routine.

Once inside, it helps with keeping skin springy and firm. It works by mimicking the skin repair signals your skin naturally sends out when it's damaged and telling it to kick into rebuild mode.

Studies have shown it can help strengthen the skin barrier as well so it's useful beyond just anti-aging.

In vitro studies suggest it can switch on genes that help skin cells grow, move around, and rebuild skin structure. Just keep in mind most of the strong evidence is from lab studies rather than large-scale clinical trials.

Lab studies suggest it can switch on genes that help skin cells grow, move around, and rebuild skin structure.

This ingredient is usually used at very low concentrations (0.002% in leave-on products).

Fungal acne note:
Usually a palmitic acid component can feed Malassezia in unbound form, but here is is covalently bonded to the peptide. This means it is very difficult for Malassezia to access, and therefore very unlikely to cause fungal acne.

Fun fact: PH is used in eye drops and injectable treatments for joint disorders. It has lubricating and tissue-repair properties.

On the emulsifier side, it keeps your formula smooth and well-mixed by playing peacekeeper for ingredients that don't naturally get along (like oil and water).

Because it has a C12 (lauric acid) fatty acid chain, this ingredient can potentially feed the Malassezia yeast that causes fungal acne. The Malassezia yeast prefers esters with C11-C24 fatty acids.

This ingredient is an ester of lauric acid and Polyglycerin-10.

In vivo studies show folic acid to decrease UV-C induced DNA damage on human fibroblasts. This is because folic acid is effective at rejoining breaks in the fibroblast DNA. It is believed folic acid may play a role in reducing UV-B damage as well. While the mechanisms are unknown, it is believed folic acid plays a role in disrupting the DNA damage process.

Studies show using moisturizers rich in folic acid led to increased hydration of the skin. Hydrated skin is essential for collagen and elastin, or for keeping skin plump. One study found a reduction in wrinkles from using folic acid creams.

Foods rich in folic acid include leafy vegetables, beans, peanuts, fresh fruit, and eggs.

The only catch is that HA isn't a single thing; it actually comes in a wide range of molecular weights (~50 - 2,000+ kDA) and size matters.

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

This is why the best HA serums blend the two sizes together so you get the best of both worlds.

The majority of cosmetic HA is produced by bacterial fermentation, typically using Streptococcus or Bacillus strains. Typical use levels in skincare sit around 0.1-2%.

A clinical study using a 0.2% low-molecular weight HA gel showed improvement in facial seborrheic dermatitis with excellent tolerance.

These are some other common types of Hyaluronic Acid:

In-vitro studies show it can enhance epidermal regeneration, boost synthesis of collagen types I, III, and IV, and improved markers of skin differentiation.

Think of skin differentiation like this: your skin cells are born at the bottom and slowly travel up to the surface as they "grow up". As they move up, they start producing specific proteins that make your skin do its job well. Two of these proteins are keratin (it makes your skin tough) and filaggrin (it breaks apart into tiny molecules to keep your skin hydrated). So Hexapeptide-9 has shown to help skin cells grow up properly and make stronger, more hydrated skin.

A manufacturer also reports increased collagen production by 117% and hyaluronic acid production by 267%.

Just know much of the published data comes from manufacturer-sponsored studies. There is a recent clinical trial showing promising anti-aging results but the evidence base is still growing.

Generally, this ingredient is well-tolerated and there's no harm in using it as a supportive ingredient in your routine.

The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane.

Trace amounts can form during production but the EU's Scientific Committee on Consumer Safety has concluded that levels at/below 10 ppm in finished products are safe (commercial products consistently fall within acceptable margins).

True allergic reactions are uncommon and the CIR Expert Panel has confirmed this ingredient to be safe as used in cosmetics.

Because it is derived from lauric acid, it may not be fungal acne safe.

Though it can't kill microbes on its own, it works as a good supporting agent when combined with other preservatives like Phenoxyethanol or 1,2-Hexanediol.

This ingredient naturally occurs as piceol in Norwegian spruce needles (~0.4-1.1% dry weight and in cloudberries). Though the cosmetic-grade material is synthesized for purity and consistency.

You'll usually see it used at low levels and suppliers recommend up to 1% added to a water phase.

Safety testing was done at concentrations like 0.05% in SPF products and 0.5% in a Human Repeated Insult Patch Test. The safety evidence is assuring; this ingredient is safe for cosmetics in current use and also holds safety status as a food flavoring as well.

An honest caveat: the "soothing" and "anti-inflammatory" claims come mostly from supplier marketing rather than published clinical trials. The Cosmetic Ingredient Review's own literature search found no useful efficacy studies on this ingredient.

So the antioxidant and preservative-boosting roles are the well supported ones while the calming benefit is plausible but thinly evidenced.

Overall, this is a well-tolerated, low-irritation multitasker that quietly helps a formula stay fresh and stable.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

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.

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.

Polyisobutene is not absorbed by the skin.

Emollients help keep your skin soft and hydrated by creating a film that traps moisture in.

In 2000, Behenyl Alcohol was approved by the US as medicine to reduce the duration of cold sores.

Fatty alcohols are usually derived from natural fats and oils and therefore do not have the same drying or irritating effect as solvent (ethanol) alcohols.

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

This ingredient may not be fungal acne safe. It is a primary fatty alcohol with a chain length above 12 carbons. A study from 2019 show Malassezia can feed on fatty alcohols in this range, so it may trigger fungal acne in those prone to it.

It plays several roles in a formula:

Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.

Multiple assessments have found it to be non-irritating and non-sensitizing to most people.

However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.

Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.

Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.

Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.

This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.

A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.

Two powerful components found in the wild soybean include genistein and diadzein. These two isoflavones are potent antioxidants with anti-inflammatory properties. Genistein in particular has been found to prevent redness caused by UV exposure.

One study from South Korea found wild soybean extract to help promote hair growth at the cellular level.

The wild soybean plant is a cousin to the famous soybean that gives us tofu, soy milk, and soy sauce.