Zymogen Galla Serum

Basically, Peg-60 Hydrogenated Castor Oil helps hold ingredients together.

Antioxidants protect your skin against damaging molecules. This may help reduce the signs of aging.

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

Tromethamine helps balance the pH level of a product. Normal pH level of skin is slightly acidic (~4.75-5.5). The acidity of our skin is maintained by our glands and skin biome. Being slightly acidic allows our skin to create an "acid mantle". This acid mantle is a thin barrier that protects our skin from bacteria and contaminants.

Oral Tromethanmine is an anti-inflammatory drug but plays the role of masking, adding fragrance, and/or balancing pH in skincare.

1,3-Propanediol, 2-amino-2-(hydroxymethyl)-

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

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.

The Cosmetic Ingredient Review (CIR) Expert Panel evaluated it (along with 22 other acryloyldimethyltaurate polymers) and concluded it's:

Due to its large molecular size, it sits on the surface of skin rather than penetrating it.

Your skin can't convert salicin to salicylic acid because it needs specific enzymes that aren't present on the skin's surface. It won't behave like true salicylic acid, especially at the concentrations used in cosmetics.

However, this ingredient has its own perks. It contains flavonoids, polyphenols, and tannins that give it proven antioxidant and soothing properties.

An 8-week clinical study found a cream with 2% of this extract improved skin microcirculation, elasticity, and dark circles. This is most likely due to its role in increasing hyaluronic acid synthesis in fibroblasts and improved vascular integrity.

Another study found a topical serum with 0.5% salicin showed improvements in visible signs of aging, hyperpigmentation, and texture.

Just be careful if you have a known aspirin/salicylate allergy and be sure to consult with a medical professional about using this ingredient if you do.

Fun fact: Willow Bark extract has been used for thousands of years and ancient civilizations used white willow to help treat pain and fevers.

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.

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.

The tannin in witch hazel has a drying effect when used on skin and constricts proteins. This helps minimize the look of large pores. The presence of tannins and fragrance may be sensitizing.

The catechins in witch hazel have anti-inflammatory properties while the gallic acid is antibacterial.

Indigenous groups have used witch hazel to help treat inflammation, which was then used by early settlers to North America.

This ingredient is derived from isobutane. It is the simplest form of a tertiary alcohol. Due to its chemical structure, it is more resistant to oxidation.

Some sources online claim T-Butyl Alcohol is a fatty alcohol. However, it is not considered one due to its chemical structure.

Studies show tannic acid may have help reduce photoaging. However, further studies are needed.

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).

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

Studies show this ingredient may be an effective wrinkle reducer as it can deeply penetrate into skin. It has also been show to help with wound healing.