L'Oreal Age Perfect Le Duo Serum

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 if this alcohol is near the end of an ingredients list, it will probably not affect your skin much.

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.

Other types of astringent alcohols include:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

As a masking agent, Dipropylene Glycol can be used to cover the smell of other ingredients. However, it does not have a scent.

Studies show Dipropylene Glycol is considered safe to use in skincare.

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

Ci 77891 is commonly found in sunscreens due to its ability to block UV rays.

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.

Caprylic Triglyceride is made by combining glycerin with coconut oil, forming a clear liquid.

While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this.

Studies have found adenosine may also help with wound healing.

In skincare products, Adenosine is usually derived from yeast.

Arginine isn't fungal acne safe when used in the presence of other lipids (fats, fatty acids, oils, esters, etc). Oils and fats occur naturally within the skin, so take caution when using Arginine if you're prone to fungal acne.

Like salicylic acid, this ingredient is a chemical exfoliant that can help break down the oil in your pores and reduce inflammation.

Though studies for LHA do show it to be less effective than salicylic acid. To be fair, salicylic acid is the reigning monarch of acne treatments.

However, a study from 2009 found LHA to be comparable to BPO, making it a good alternative for people with sensitive skin. Another study of 14 patients found a significant decrease in comedones after using LHA.

Another pro of LHA? It is less irritating than salicylic acid due to its large molecule size.

Large molecules cannot penetrate skin as well, so they are gentler on the skin. LHA is much less penetrative than salicylic acid.

An in-vitro study (not done on a living organism) found only 6% of LHA penetrated past the statum corneum compared to 58% of salicylic acid. An in-vivo (done on a living organism) analysis revealed ~17% of LHA was still present in the top layer of skin after 4 days, versus ~9% of salicylic acid.

Interestingly, a study from 2008 found LHA comparable to another famous acid, glycolic acid.

This study found about 10% of LHA is as effective as 20-50% of glycolic acid in treating hyperpigmentation and fine-lines.

Hydroxy acids have been found to stimulate skin protein, lipids, and thermal thickening. This may have anti-aging benefits.

Copper has wound healing properties due to its role in creating new blood vessels and tissue repair.

Glucose is hydrating due to its humectant property. As a humectant, glucose draws moisture from the air and from deeper levels in the skin.

Our skin contains many sugars that act as prebiotics and help strengthen our natural microbiome. Having a healthy microbiome helps protect our skin from harmful bacteria and other contaminants.

Studies show glucose may help with fading discoloration and pigmentation. This is because our skin metabolizes glucose into lactic acid. Lactic acid is an AHA that helps exfoliate the top layer of skin.

As collagen is made up of glycine and other amino acids, it is believed glycine may help our skin produce more collagen.

One study found histidine and carnosine to be a dynamic duo for your skin:

Oral histidine has also been found to help with filaggrin-deficit skin disorders such as atopic dermatitis.

Why is it considered a semi-essential amino acid? This is because adults are able to create it but children must get it from their diet.

This ingredient has many benefits. These benefits include boosting collagen production, fighting inflammation, and reversing UV damage.

By preventing our bodies from producing interleukins, Palmitoyl Tetrapeptide-7 helps fight inflammation. An interleukin is a chemical that signals to the body to produce an inflammatory response. Interleukin production is accelerated by UV radiation.

Palmitoyl Tetrapeptide-7 tells our body to create more collagen. Collagen is a protein that makes connective tissue. Boosting collagen production leads to a healthier skin barrier. Having a healthy skin barrier means having firm and hydrated skin.

Read more about other common types of peptides here:

Palmitoyl Tripeptide-1 can help reduce wrinkles and make the skin look more youthful.

Read more about other common types of peptides here:

Two structures of phenylalanine exist: L-phenylalanine and D-phenylalanine. L-phenylalanine is essential, this means our bodies cannot produce it naturally and we must get it from foods. Our bodies convert D-phenylalanine to neurotransmitters, and D-phenylalanine is found in our bodies naturally.

Some foods that contain L-phenylalanine include eggs, soybeans, beef, milk.

In medicine, proline is used as an osmoprotectant. This means it helps prevent oxidative degradation in other drugs.

Our bodies are able to produce proline naturally, but certain conditions may inhibit this production. In that case, proline can be obtained from eating egg whites, soy protein, dairy products, asparagus, mushrooms, and seaweed.

Serine is a non-essential amino acid, meaning we don't need to obtain it from eating foods.

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:

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.

This ingredient has skin conditioning, anti-inflammatory, and humectant properties. Humectants help hydrate your skin by drawing moisture from the air. This helps keep your skin moisturized.

This ingredient can either be derived from an animal product or be synthetically created.

Ascorbyl Glucoside is an antioxidant. Antioxidants help fight free-radicals, or molecules that may damage skin cells.

It can help to reduce redness, improve skin texture, reduce the effects of aging, reduce the visibility of dark spots, and brighten skin.

Read more about other types of Vitamin C:

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.

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.

Large amounts of vitamin E found in argan oil helps the skin retain water. Argan oil also contains fatty acids such as linoleic acid, oleic acid, and palmitic acid. It is also a good source of lipids.

Another benefit of argan oil is skin-soothing. It can help reduce inflammation-related skin symptoms.

Argan Oil is effective at regulating sebum production in pores. This can make it effective at treating hormonal acne.

Traditionally, argan oil was used for its antibacterial and antifungal properties. However, argan oil contains fatty acids that may make it not fungal-acne safe.

Argan Trees are native to Morocco.

According to a manufacturer, it helps create a "smooth, light and fresh" texture.

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.

If you spot Citric Acid near the end of an ingredient list, it's likely there as a pH adjuster rather than an active ingredient.

Read more about some other popular AHA's here:

As an emollient, the fatty acids in soybean oil helps keep your skin soft and hydrated. It does so by creating a film on top that traps moisture in.

Soybean oil is also rich in vitamin E, a potent antioxidant. Vitamin E is also anti-inflammatory and provides a soothing effect.

Studies show soy may help fade hyperpigmentation from UVB. It does so by disrupting the melanin process from UVB induced skin inflammation.

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

Soybeans are rich in proteins and are part of the legume family. Foods made with soybeans include tofu, soymilk, edamame, miso, and soy sauce.

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.

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.

High percentages of Sodium Lactate can have an exfoliating effect.

Fun fact: Sodium Lactate is produced from fermented sugar.

Limonene acts as an antioxidant, meaning it helps neutralize free radicals.

When exposed to air, oxidized limonene may sensitize the skin. Because of this, limonene is often avoided by people with sensitive skin.

The term '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.

This ingredient has a scent that is floral, spicy tropical, and citrus-like.

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.