reviv serums Revivhair Max Hair Stimulating Serum

The bark of Larix Europaea is rich in antioxidants and plant compounds such as flavonoids, spiro-polyphenols, and procyanidins.

Flavonoids are naturally occurring compounds found in many plantsand foods like tea, wine, and chocolate. They’re known for their strong antioxidant and anti-inflammatory properties.

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).

The main ingredient in redensyl is Larix Europaea Wood Extract.

Recent clinical work on a proprietary Astragalus + Centella saponin system showed improvement in skin aging and quality.

Overall, this ingredient is a great supportive ingredient with low irritation risk.

In your eyelash follicles, it activates the keratin gene and promotes nutrient absorption into the follicle. This translates to thicker and longer eyelashes over time.

Besides stimulating keratin production for lash growth, this ingredient enhances the delivery of other active ingredients in a formula.

The clinical evidence is still pretty early-stage at this point. A 90 day study in 29 participants found improvements in lash length (10.52%), volume (9.3%), thickness (35%), and curl (50.83%) with no adverse reactions reported.

You might have heard that eyelash serums can cause pigmentation change in eye color to turn eyes brown. This is associated with a different class of lash serum ingredients: prostaglandin analogs.

Myristoyl Pentapeptide-17 is a different thing entirely and has no known association with iris pigmentation changes. The 90 day study noted no adverse effects around the eye area at all.

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).

A small human study using a mascara with 2% Biotinoyl Tripeptide-1 reported lashes that were about 17% longer and 19% thicker after one month.

One study from 2025 compared topical spray vs. a combined tropical/oral treatment. The combination group saw greater increases in total hair count.

While these early results are encouraging, most of the data comes from in-vitro experiments (in test tubes) or small, short-term trials.

Biotinoyl Tripeptide-1 looks promising for supporting hair strength and growth but there’s not yet strong clinical evidence to confirm how well it works.

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.

Fun fact: Mannitol can be found in foods as a sweetener. It can be naturally found in mushrooms, algae, fruits, and veggies.

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.

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.

Antioxidants help fight free-radical molecules. Free-radical molecules are capable of damaging our cells and other genetic material. Antioxidants help stabilize free-radicals by donating extra electrons. Grape seed extract may help reduce the signs of aging.

The antimicrobial properties of grape seed may help treat acne. However, more research is needed to support this claim.

Grape seed has also been found to help absorb UV rays. Grape seed extract should not replace your sunscreen.

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 can also form a thin protective film on skin. One study found that a formula using this polymer helped slow down how quickly other ingredients (like DEET) were absorbed through skin.

A 2024 study of over 1,300 patients confirmed that sensitization to this ingredient is rare. It is also non-mutagenic and has a clean track record.

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:

Fun fact: Methionine can be found in meat, fish, and dairy. It cannot be naturally produce and requires dietary intake.

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.

Due to its large molecule size, it doesn't penetrate beyond the skin's surface.

This ingredient has a solid regulatory track record; the CIR Expert Panel first concluded it was safe for use in cosmetics at concentrations up to 100% in 1997. A 2012 reassessment reaffirmed that finding. Safety studies have also found no irritation or evidence of toxicity.

A 2019 study did find this ingredient to grow Malassezia, so this ingredient may not be fungal acne safe.

Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.

"Alkaline" refers to a high pH level. A low pH level would be considered acidic.

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

This ingredient is also pretty picky about pH; it performs best at pH 6.5 or below.

At the right pH level, sorbic acid is "active" and can slip through the outer wall of a microbe. Once inside, it turns the cell's interior more acidic to shut down the microbe from the inside.

The EU caps this ingredient at 0.6% while the CIR has concluded it's safe at concentrations up to 1%. It's most often used around 0.05-0.2% in cosmetics.

Though this ingredient is considered low-sensitizing and well-tolerated, a very small number of people may have a contact allergy to it. Be sure to patch test if you have a history of allergies towards preservatives.