De Magistrale Bereider Tretinoïne 0,05% Crème

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.

This ingredient gets a bad rep because it is irritating and drying due to its astringent property. Astringents draw out natural oils in tissue to constrict pores and dry out your skin.

However, alcohol denat. is not all that bad.

Due to its low molecular weight, alcohol denat. tends to evaporate quickly. One study on pig skin found half of applied alcohol evaporated in 10 seconds and less than 3% stayed on skin.

This also helps other ingredients become better absorbed upon application.

Studies are conflicted about whether this ingredient causes skin dehydration. One study from 2005 found adding emollients to propanol-based sanitizer decreased skin dryness and irritation. Another study found irritation only occurs if your skin is already damaged.

Small amounts of alcohol are generally tolerated by oily skin or people who live in humid environments.

The rule of thumb is this ingredient will probably not affect your skin much if it is near the end of an ingredients list.

One thing to note:
People with ALDH2 (aldehyde dehydrogenase 2) deficiency may experience skin irritation from continued alcohol use. About 8% of the world's population have this deficiency.

The Cosmetic Ingredient Review Expert Panel has determined denatured alcohols to be safe for use in concentrations between 0.05% and 12% (depending on which denaturant is used).

Also...

This ingredient has antimicrobial and solvent properties.

The antimicrobial property helps preserve products and increase their shelf life. As a solvent, it helps dissolve other ingredients.

Look for formulas that contain glycerin, hyaluronic acid, or panthenol if you want to offset any drying effect.

This ingredient will trip away your skin's natural oils/lipids that help it lock in moisture. This can worsen dryness, trigger eczema flare-ups, and aggravate rosacea.

Be sure to patch test any product with this ingredient if you have dry or sensitive skin, eczema, or rosacea.

Inside your skin cells, it binds to receptors called retinoic acid receptors and switches on the genes that control how skin cells behave.

For acne, it helps your skin shed dead cells properly instead of letting them build up and clog your pores (this is what turns into blackheads and pimples). It also calms redness/swelling, which is why it's a FDA-approved acne treatment.

Tretinoin also tells your skin to make more collagen and slows down the stuff that breaks collagen apart too. Over time, your skin looks smoother, softer, and more even, with fewer lines lines and sun spots.

The evidence for this ingredient is strong:

A systematic review of randomized controlled trials found that topical tretinoin consistently improved wrinkles, pigmentation, sallowness, and dark spots. Results typically showed up as early as one month and lasted out to 24 months.

All studies also found this ingredient to be safe and well-tolerated.

Typical concentrations run from about 0.01-0.1%, with 0.025%-0.1% being the usual range studied for photoaging and a 0.05% cream producing measurable wrinkle/roughness improvements in large six-month trials.

The main trade-off is irritation; dryness, peeling, redness, and sun sensitivity are common in the first few weeks so be sure to pair it well with a good moisturizer and daily sunscreen.

Learn about a form of retinoid you can purchase at the store, retinol.

As a preservative, it is used to stabilize products and prevent them from degrading. Specifically, BHT prevents degradation from oxidation.

The concerns related to BHT come from oral studies; this ingredient is currently allowed for use by both the FDA and EU.

However, it was recently restricted for use in the UK as of April 2024.