Kenra Curl Glaze Mousse 13

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 CIR Expert Panel has confirmed this ingredient to be nontoxic and clinical studies show no sensitization at cosmetic use concentrations.

True allergic reactions are quite rare: a 15-year retrospective study of 6,751 patients found only 0.31% had a positive reaction (and less than half were considered clinically relevant).

It seemed that when sensitization does occur, it's most commonly linked to topical medication (like corticosteroids) and not cosmetics. Allergic contact dermatitis also appears largely limited to individuals with underlying skin conditions.

Overall, propylene glycol is a well-studied ingredient that most people can tolerate without issue.

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.

Typically, it's used in cosmetic products to protect them from deterioration caused by UV rays. This is why you'll find it in a lot of products that aren't sunscreens.

It is typically used at very low levels in cosmetics, with most formulations using 0.0125% or less (well below its approved maximum).

In the EU, IPBC concentration limits are set at 0.02% in rinse-off products and 0.01% in leave-on products.

Though IPBC is a relatively uncommon contact allergen, patch testing studies show positive reaction rates ranging from 0.3%-0.9% of patients tested. This is still quite low compared to preservatives like methylisothiazolinone which sits at around 4-5%.

Researchers note that existing iodine sensitives or rubber allergies may be the cause of this as IPBC shares a structure with both thiuram (used in rubber) and iodine.

Be sure to patch test if you are unsure and speak with a medical professional about using this ingredient.

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.

Due to its fatty acid content, Jojoba oil may not be fungal acne safe.

Some people who are allergic to imidazolidinyl urea also react to diazolidinyl urea. It ranked as the 14th most common allergen in patch tests from 2005–06.

Safety reviews show that at concentrations under 0.5%, the formaldehyde released remains below the accepted safety limit, making it considered safe for cosmetic use.

Ultimately, its safety depends on individual skin sensitivity and personal comfort with formaldehyde-releasing preservatives.

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.

It doesn’t protect you from the sun, but it can help your skin bounce back after too much time in it.

Let’s get into the details:

Aloe contains antioxidant Vitamins A, C, and E, which help fight off free radicals (unstable molecules from things like pollution that can damage your skin).

It’s also rich in polysaccharides, which are natural sugars that help hydrate the skin by acting like the skin’s own moisturizing agents. These, along with other sugars like monosaccharides, help form a protective barrier that locks in moisture.

Aloe works as both a humectant and an emollient. That means it draws water into the skin (humectant) and helps trap it there (emollient), making it an effective natural moisturizer.

You’ll also find a mix of other skin-supporting ingredients in aloe, including folic acid, choline, calcium, amino acids, fatty acids, and even Vitamin B12.

Out of the 420+ species of aloe, Aloe barbadensis is the most widely used in skincare products thanks to its gentle yet effective properties.

There are over 420 species of aloe but Aloe Barbadensis is the most commonly used for topical products.

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.

The fatty acids found in sunflower seeds include (from highest amount to least): linoleic acid, myristic acid, palmitic acid, stearic acid, arachidic acid, oleic acid, and linolenic acid.

These fatty acids hydrate your skin. Emollients create a film on the skin to prevent moisture from escaping.