Peter Thomas Roth Even Smoother Glycolic Retinol Resurfacing Serum

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.

"Alkaline" refers to a high pH level. A low pH level would be considered acidic.

It also contains Vitamin E, a great moisturizing ingredient. Vitamin E is also an antioxidant and protects your skin against oxidative damage.

This ingredient humectant properties, meaning it helps draw moisture from the air. This helps keep your skin hydrated.

While jojoba has antibacterial properties, it is only able to kill some strains of bacteria.

Studies also show it helps in wound healing. In fact, Indigenous cultures have used jojoba as a moisturizer and to help treat burns for centuries.

Fun fact: Jojoba oil similar to natural human skin sebum, so it has a great effect on dry skin. It is also promising with helping to regulate sebum production.

Due to its fatty acid content, Jojoba oil may not be fungal acne safe. We recommend speaking with a professional if you have any concerns.

Cornstarch is a common food ingredient used to thicken soups or to make corn syrup.

As an emollient, it helps soften skin and supports barrier-replenishing ingredients.

In cosmetics, Glyceryl Stearate is often made from vegetable oils or synthetically produced.

This ingredient may not be fungal-acne safe

Fun fact: The human body also creates Glyceryl Stearate naturally.

Other benefits include smoothing wrinkles and minimizing redness.

The cherry on top? Niacinamide can also help build keratin, a protein that keeps skin firm.

When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.

Niacinamide can be mixed with other ingredients to boost benefits. For instance, it has shown to be effective when used with copper, folic acid, and zinc to treat acne.

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.

Due to this fatty acid content, this ingredient may not be fungal-acne safe.

Fun fact: Our skin uses fatty acids, and especially linoleic acid, for creating ceramides.

Linoleic acid helps moisturize your skin as an emollient. Emollients act as a thin film to prevent moisture from escaping.

Cartenoids are an antioxidant. Antioxidants protect your skin against external damage. They also give pumpkins their classic orange color.

Fun fact: Pumpkins were first domesticated in Southern Mexico about 10,000 years ago.

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

Biologically, collagen is responsible for keeping skin firm and youthful. Collagen is comprised mostly of glycine, proline, and hydroxypoline. These are amino acids.

Collagen will not increase sun sensitivity, but you should always wear sunscreen during the day.

Learn more about hydrolyzed collagen here.

Studies have found adenosine may also help with wound healing.

In skincare products, Adenosine is usually derived from yeast.

Squalane comes from squalene, which occurs naturally within the sebum of our skin. It is one of the oils our skin produces to keep itself hydrated. Squalane is the hydrogenated version of squalene and has a longer shelf life.

Research shows that squalane is non-irritating (even at 100% concentration).

In general, it's a fantastic ingredient. It does a great job at hydrating the skin, and it's suitable for those with sensitive skin.

The source of squalane may impact malassezia / fungal acne. This is because olive oil derived squalane can contain impurities such as fatty acids and plant waxes. Sugarcane derived squalane is recommended for anyone with malassezia concerns.

Is squalane vegan?

This depends on the source. Squalane can be derived from both plants and animals. Most squalane used in skincare comes from plants.

Please note: the source of squalane is only known if disclosed by the brand. We recommend reaching out to the brand if you have any questions about their squalane.

Read more about squalene with an "e".

Allantoin is derived from the comfrey plant but produced synthetically for cosmetic products to ensure purity.

Vitamin C is best used for brightening skin. It improves dark spots, acne scars, and hyperpigmentation. This is because it blocks the process of skin darkening when exposed to UV.

Remember: Vitamin C should not replace sunscreen!

Your skin uses vitamin C to build collagen. Collagen is one key component in having a strong skin barrier and plump skin. Vitamin C also plays a role in regulating collagen, thus making it effective in improving wrinkles and fine lines.

Ascorbic acid shows potent antioxidant activity. As an antioxidant, it helps fight free-radicals. Free-radicals are molecules that may damage your skin cells. These antioxidants also protect skin against UV damage.

The best formulations include Vitamin E and/or ferulic acid. These two ingredients help stabilize and provide a boost in the benefits of ascorbic acid. This is because ascorbic acid becomes unstable when exposed to UV and air. In fact, you can tell your ascorbic acid has oxidized when it turns an orange-yellow color.

Ascorbic acid is generally compatible with other ingredients. However, using ascorbic acid with other active ingredients might cause irritation. Two ingredients: copper ions and benzoyl peroxide, will inactivate ascorbic acid completely.

Read more about other types of Vitamin C:

Foods rich with vitamin C include oranges, strawberries, broccoli, bell peppers, and more. When consuming Vitamin C, your skin receives a portion of the nutrients.

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.

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.

Ceramides are an important building block for our skin barrier. A stronger barrier helps the skin look more firm and hydrated. By bolstering the skin ceramides act as a barrier against irritating ingredients. This can help with inflammation as well.

If you would like to eat ceramides, sweet potatoes contain a small amount.

Read more about other common types of ceramides here: Ceramide AP Ceramide EOP

Due to it being edible and tasteless, you'll likely find this ingredient in breath freshener strips. This ingredient is produced from the starch of the fungus, Aureobasidium pullulans.

Pullulan is stable over a broad-range of pH.

Polysorbate 20 also adds scent to a product. Since it is made using sorbitol, it has a sweet scent. Sorbitol can also be found in fruits such as apples and peaches.

The lauric acid used to create Polysorbate 20 is often derived from coconuts.

Polysorbate 20 may not be fungal acne safe.

Silica is present naturally within the skin during collagen production and when reducing inflammation.

Sodium Hyaluronate is naturally occurring in our bodies and is mostly found in eye fluid and joints.

These are some other common types of Hyaluronic Acid:

This ingredient has antimicrobial properties and helps prevent the growth of bacteria in a product.

Leuconostoc is used to make the traditional Korean side-dish, kimchi. It is also used to make sourdough bread (both incredibly yummy foods).

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.

As an emulsifier, Sclerotium Gum helps prevent ingredients from separating, such as water and oil.

Once applied, Coco-Caprylate/Caprate is absorbed quickly and leaves a silky feel.

Coco-Caprylate/Caprate may not be fungal acne safe.

Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.

It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.

Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.

We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

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.

This ingredient is used in medicine to help treat low blood levels of phosphorus.

Behenyl Alcohol is usually derived from the fats in vegetable oils.

In 2000, Behenyl Alcohol was approved by the US as medicine to reduce the duration of cold sores.

Other types of astringent alcohols include:

According to the National Rosacea Society based in the US, you should be mindful of products with these alcohols in the top half of ingredients.

Any type of sanitizing product will have high amounts of alcohol to help kill bacteria and viruses.

Fatty alcohols come from plant oils such as coconut oil. These can help hydrate the skin and are non-irritating. Some fatty alcohols include cetyl and stearyl alcohol.

Mica has been used since prehistoric times throughout the world. Ancient Egyptian, Indian, Greek, Roman, Aztec, and Chinese civilizations have used mica.

Mica can be naturally found throughout the world. However, some sources of mica may be controversial. In 2016, mica mined in the Jharkhand state in India was found to be using child labor. However, companies are able to source ethical mica affiliated with international organizations that monitor the mica supply chain.