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You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.

In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.

If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.

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.

When you apply niacinamide to your skin, your body converts it into nicotinamide adenine dinucleotide (NAD). NAD is an essential coenzyme that is already found in your cells as "fuel" and powers countless biological processes.

In your skin, NAD helps repair cell damage, produce new healthy cells, support collagen production, strengthen the skin barrier, and fight environmental stressors (like UV and pollution).

Our natural NAD levels start to decline with age, leading to slower skin repair, visible aging, and a weaker skin barrier. By providing your skin niacinamide, you're recharging your skin's NAD levels. This leads to stronger, healthier, and younger looking skin.

Another name for vitamin B3 is nicotinamide. This vitamin is water-soluble and our bodies don't store it. We obtain Vitamin B3 from either food or skincare. Meat, fish, wheat, yeast, and leafy greens contain vitamin B3.

The type of niacinamide used in skincare is synthetically created.

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.

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

As a humectant, it helps draw moisture from the air to your skin. This helps your skin stay hydrated.

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.

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.

Some other names for this ingredient include soy lecithin and deoiled soy lecithin.

When applied to the skin, ectoin helps bind water molecules to protect our skin. The water forms a sort of armor for the parts of our skin cells, enzymes, proteins, and more.

Besides this, ectoin has many uses in skincare:

A study from 2004 found ectoin to counteract the damage from UV-A exposure at different cell levels. It has also been shown to protect skin against both UV-A, UV-B rays, infrared light, and visible light.

Studies show ectoin to have dual-action pollution protection: first, it protects our skin from further pollution damage. Second, it helps repair damage from pollution.

In fact, ectoin has been shown to help with:

Fun fact: In the EU, ectoin is used in inhalation medication as an anti-pollution ingredient.

Ectoin is a highly stable ingredient. It has a wide pH range of 1-9. Light, oxygen, and temperature do not affect this ingredient.

While studying wound healing, researchers noticed GHK-Cu stimulated hair follicle enlargement and growth by keeping hair in its active growth phase longer. This has made it a promising ingredient for hair regrowth treatments.

Some people have reported increased facial hair. While GHK-Cu can make your hair follicles bigger, it usually doesn’t turn soft, barely-visible facial hairs into thick, dark ones.

Anecdotal reports suggest that overusing copper peptides might lead to premature aging due to excess free copper or enzyme imbalances. This claim isn’t backed by large-scale studies.

Unfortunately, there are limited human studies for this ingredient. While early results are promising, many studies are either small, in-vitro, or not rigorously controlled.

For example, there is a 1998 study that explored the effects of copper tripeptide, vitamin C, tretinoin, and melatonin on skin repair and collagen synthesis.

After one month, increased procollagen production was seen in 7 out of 10 participants using copper tripeptide (more than those using vitamin C, melatonin, or tretinoin.

While the study was exploratory, it offers early evidence that copper tripeptide may support collagen production. Larger, well-designed trials are still needed to confirm its potential and understand individual responses.

Read more about other common types of peptides here:

In this case, the 60 comes from reacting 60 units of ethylene oxide with sorbitan.

Polysorbates are commonly used in medicine and foods.

Due to its isostearic acid base, it may not be safe for Malassezia or fungal acne.

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.

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.

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.

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

Like other alcohols, this ingredient helps prevent the growth of bacteria. However, its main purpose is to impact a fragrance.

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.

An in-vitro study from 2024 found glutamic acid to play a role in inhibiting inflammation and thus a potential skin-soothing ingredient.

Other studies show it to be have potential wound healing, skin barrier repair, and hair growth properties.

Glutamic acid has poor solubility in water and other solvents.

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

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

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:

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

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.

Beyond smoothing, Argireline may also support collagen production. Collagen is the protein that helps keep your skin firm, bouncy, and well-hydrated by strengthening the skin barrier.

So while Argireline isn’t a miracle fix, it can be a helpful addition to a routine focused on both prevention and skin health.

Read more about other common types of peptides here: