Clinique Smart Clinical Repair Broad Spectrum SPF 30 Wrinkle Correcting Cream Versus Estée Lauder Daywear Multi-Protection Anti-Oxidant 24H-Moisturizer Creme SPF 15

Photostabilizers help stabilize UV-filters and prevents them from degrading quickly.

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.

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

On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.

One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too strong if you have sensitive skin).

Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.

You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.

The ethylhexanol in this ingredient is a fatty alcohol and helps hydrate your skin, similar to oils. It is an emollient, which means it traps moisture into the skin.

According to manufacturers, Ethylhexyl Salicylate absorbs UV wavelength of 295-315 nm, with a peak absorption at 307-310 nm. UVA rays are linked to long term skin damage, such as hyperpigmentation. UVB rays emit more energy and are capable of damaging our DNA. UVB rays cause sunburn.

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.

It plays well with most ingredients and is typically used at 0.1-1%. However, concentrations up to 50% have been reported in moisturizers.

Depending on the source of this ingredient, lecithin may not be fungal acne safe. This is because some sources of lecithin come from soybean oil, which may feed the malassezia yeast that causes fungal acne.

We recommend reaching out to the brand you are purchasing from to inquire about the source of their lecithin.

This property also makes Pentylene Glycol a great texture enhancer. It can also help thicken or stabilize a product.

Pentylene Glycol also acts as a mild preservative and helps to keep a product microbe-free.

Some people may experience mild eye and skin irritation from Pentylene Glycol. We always recommend speaking with a professional about using this ingredient in your routine.

Pentylene Glycol has a low molecular weight and is part of the 1,2-glycol family.

At its maximum recommended strength of 4%, this ingredient is not likely to make a significant contribution to SPF factor. Polycrylene has a large molecular weight so it's unlikely to penetrate skin.

Although rare, this ingredient can cause contact dermatitis.

Due to regulatory loopholes, you'll be able to find this chemical UV filter in "100% mineral" sunscreens.

Both potassium sorbate and sorbic acid can be found in baked goods, cheeses, dried meats, dried fruit, ice cream, pickles, wine, yogurt, and more.

You'll often find this ingredient used with other preservatives.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

Fatty alcohols are usually derived from natural fats and oils and therefore do not have the same drying or irritating effect as solvent (ethanol) alcohols.

The FDA allows products labeled "alcohol-free" to have fatty alcohols.

Tocopheryl Acetate is commonly found in both skincare and dietary supplements.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!