Callyssee Doppio Firming Eye Serum

Emollients help hydrate the skin by creating a thin barrier. This thin barrier prevents moisture from escaping.

Unlike other plant oils, jojoba wax doesn't easily penetrate skin. It mostly works in the uppermost layers as an emollient. This just means it forms a light barrier on the skin to help retain moisture.

Formulations with jojoba esters up to 90% reduced transepidermal water loss (TEWL) and increased barrier recovery by 81% (outperforming bisabolol at 47%).

Besides barrier support, the science also suggests jojoba to have anti-inflammatory effects and potential applications for skin infections, aging, and wound healing.

Fun fact: Indigenous cultures have used jojoba as a moisturizer and to help treat burns for centuries.

Fungal acne: The Malassezia yeast is known to metabolize fatty acids in the C11-24 range and jojoba's dominant fatty acid components fall into this range. This ingredient may not be fungal acne safe.

On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.

Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.

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%.

It helps with dark spot fading by interfering with the process of skin darkening, helping to reduce hyperpigmentation. Like other forms of vitamin C, this ingredient encourages the skin to create more collagen.

As an antioxidant, it helps fight free-radicals. Free-radicals are molecules that may damage your skin cells.

One study found Ascorbyl Tetraisopalmitate to degrade in sunlight, but is stabilized when combined with acetyl zingerone.

A clinical study found that applying 0.5% bisabolol daily for 8 weeks produced an average 9% decrease in skin pigmentation. Researchers found it can also suppress the process that leads to excess melanin production in skin.

In vitro studies found that bisabolol combined with propylene glycol significantly increased skin permeability by increasing lipid fluidity in the stratum corneum.

You'll likely see use concentrations quite low, usually 0.1-0.2%.

Overall, this is a well-tolerated ingredient that works well in formulas designed for sensitive, reactive, or post-procedure skin.

CASE contains several ingredients that protect and soothe skin. These include caffeine, polysaccharides, sucrose, lipids, minerals, and proteins.

The star ingredient in coffee is caffeine.

Caffeine helps with anti-aging, antioxidant, and photo-protection.

How? It has been shown to block collagenase (~41%), elastase (~35%), and tyrosinase (~13%).

Collagenase and elastase are enzymes that break down collagen and elastin, respectively. Tyrosinase is the enzyme that controls melanin production.

Our skin creates melanin when exposed to UV as a defense mechanism.

It should be noted most studies looked at caffeine's ability to inhibit damage from UV-B rays.

According to a manufacturer, this ingredient is often dissolved using water, glycerin, and propanediol. The caffeine content of this ingredient is about 100 ppm.

Coffea Arabica is native to Ethiopia.

This ingredient has a scent that is floral, spicy tropical, and citrus-like.