Sunday Riley A+ High-Dose Retinol Serum Versus First Aid Beauty Skin Lab Retinol Serum .25% Pure Concentrate

It has the most scientific studies backing up its skin benefits out of all the non-prescription ingredients.

Retinol is proven to:

This is why retinol is effective at removing wrinkles, fading dark spots, treating acne, and reducing the appearance of pores.

Studies show retinol is less effective when exposed to UV. Be sure to look for appropriate packaging to keep your retinol potent (similar to Vitamin C).

Using retinol or any retinoids will increase sun-sensitivity in the first few months. Though studies show retinoids increase your skin's natural SPF with continuous use, it is best to always wear sunscreen and sun-protection.

We recommend speaking with a medical professional about using this ingredient during pregnancy.

Retinol may cause irritation in some people, so be sure to patch test. Experts recommend 'ramping up' retinol use: start using this ingredient once a week and work up to using it daily.

Read about Tretinoin

As an emollient, lecithen helps soften the skin and creates a barrier to keep moisture in.

As an emulsifier, it also helps prevent water and oil ingredients from separating. Lecithin can also help ingredients be better absorbed by the skin.

This is because the phospholipids in lecithin produce liposomes. Liposomes help other ingredients get through the skin barrier.

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 feeds fungal acne.

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

Though Caprylyl Glycol is an alcohol derived from fatty acids, it is not the kind that can dry out skin.

This ingredient is also used as a preservative to extend the life of products. It has slight antimicrobial properties.

Polysorbate 80 may not be fungal acne safe.

Stearic acid may also be used to enhance the texture of products. It can add volume and stabilize ingredients such as water and oil. This can help water and oil ingredients from separating.

Sources of stearic acid include animal or vegetable fats/oils such as coconut or shea. It can be naturally found in butter, cocoa butter, shea butter, vegetable fats, and animal tallow.

This ingredient may not be Malassezia folliculitis, or fungal-acne safe.

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.

Another benefit is a bit of UV protection. Vitamin E helps reduce the damage caused by UVB rays. (It should not replace your sunscreen). Combining it with Vitamin C can decrease sunburned cells and hyperpigmentation after UV exposure.

You might have noticed Vitamin E + C often paired together. This is because it is great at stabilizing Vitamin C. Using the two together helps increase the effectiveness of both ingredients.

There are often claims that Vitamin E can reduce/prevent scarring, but these claims haven't been confirmed by scientific research.