Is Clinical Active Peel System

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

Glycolic acid is a derivative of sugarcane. While glycolic acid is an AHA with exfoliating properties, sugarcane is not an AHA.

A study from 2021 found the compounds in sugarcane extract to have antioxidant, antimicrobial, and anti-inflammatory activity. The study also suggests these compounds can inhibit skin ageing enzymes and promote collagen synthesis.

Unless it is specified to be non-alcohol, many types of witch hazel ingredients are distilled in denatured alcohol.

Witch Hazel water is an astringent, anti-inflammatory antioxidant, and antibacterial ingredient.

It contains tannins. Tannins have a drying effect when used on skin by constricting proteins. The constriction also minimizes the appearance of pores.

Both the tannins and fragrance found in witch hazel may be skin-sensitizing.

Witch hazel water gets anti-inflammatory and antibacterial properties from its catechin and gallic acid content.

Indigenous groups have used witch hazel to help treat inflammation in North America for centuries.

This property also makes Pentylene Glycol a great texture enhancer. It can also help thicken or stabilize a product.

Pentylene Glycol also acts as a mild preservative and helps to keep a product microbe-free.

Some people may experience mild eye and skin irritation from Pentylene Glycol. We always recommend speaking with a professional about using this ingredient in your routine.

Pentylene Glycol has a low molecular weight and is part of the 1,2-glycol family.

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:

Salicylic acid is also known for its soothing properties. It has a similar structure to aspirin and can calm inflamed or irritated skin, making it a good option for acne-prone skin that is also sensitive.

Concentrations of 0.5-2% are recognized by the U.S. FDA as an over-the-counter topical acne product.

It can cause irritation and/or dryness if one's skin already has a compromised moisture barrier, so it's best to focus on repairing that before introducing this ingredient into your routine.

While salicylic acid does not increase sun sensitivity, it’s still important to wear sunscreen daily to protect your skin.

If you are looking for the ingredient called BHA or Butylated Hydroxyanisole, click here.

Aloe Barbadensis Leaf Juice also contains sugars. These sugars come in the form of monosaccharides and polysaccharides, folic acid, and choline. These sugars are able to help bind moisture to skin.

It also contains minerals such as calcium, 12 anthraquinones, fatty acids, amino acids, and Vitamin B12.

Vaccinium Myrtillus Fruit Extract also helps reduce irritation.

It can also be mildly exfoliating due to the citric acid, an AHA.

Citrus fruits are rich in flavonoids, alkaloids, and vitamin C.

And of course, lemons are rich in Vitamin C. Vitamin C helps with skin-brightening and increasing collagen production.

The acidity of lemons may work as an astringent for acne.

However, lemons can also cause skin sensitivity due to its limonene content. It can also increase photosensitivity, or sensitivity to the sun.

This ingredient is also used to add a lemon scent to products.

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).

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

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

Menthol also has antimicrobial properties.

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%.

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.

Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.

Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.

This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

As a polysaccharide, Maltodextrin has moisturizing properties. Polysaccharides are a type of carbohydrate. The top layer of skin uses polysaccharides to retain water, keeping the skin hydrated.

Maltodextrin is water soluble and has a sweet taste.

Lycopene is a potent antioxidant. Besides helping to protect your skin against free-radical molecules, it also helps soothe the skin. Lycopene gives watermelon the distinct red color.

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.

Recent research shows topical glycogen can help improve skin moisture, support barrier function, and increase the rate of keratinocyte production. Some studies also suggest this ingredient can protect our skin from oxidative stress.

Biologically, animals and some microorganisms use glycogen as an energy-storage molecule.

This ingredient is usually derived from marine or plant sources, but can sometimes come from animals. We recommend reaching out to the brand if you have questions about the source of their glycogen.

This ingredient has skin conditioning, anti-inflammatory, and humectant properties. Humectants help hydrate your skin by drawing moisture from the air. This helps keep your skin moisturized.

While succinic acid posesses antimicrobial, antioxidant, and anti-inflammatory properties, these properties have not been studied in skincare products.

Fun fact: Succinic acid was known as the 'spirit of amber' in the past. This is because it used to be derived from distilling amber.

While glutathione is said to help with fading dark spots, the results from research are inconclusive. Further studies are needed. With that said, gluthatione has been shown to protect our skin from UV-B induced damage.

This ingredient is naturally occurring in plants, animals, fungi, and some bacteria.

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.

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.

It is soluble in water. The number '8' stands for the molecular weight of the ingredient.

High percentages of Sodium Lactate can have an exfoliating effect.

Fun fact: Sodium Lactate is produced from fermented sugar.

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.

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