Arencia Red Smoothie Serum 30

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.

Kojic Acid is a similar ingredient.

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.

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.

Methylpropanediol is able to add a bit of moisture to the skin. It also helps other ingredients be better absorbed into the skin, such as salicylic acid.

The Cosmetic Ingredient Review (CIR) Expert Panel evaluated it (along with 22 other acryloyldimethyltaurate polymers) and concluded it's:

Due to its large molecular size, it sits on the surface of skin rather than penetrating it.

It can also form a thin protective film on skin. One study found that a formula using this polymer helped slow down how quickly other ingredients (like DEET) were absorbed through skin.

A 2024 study of over 1,300 patients confirmed that sensitization to this ingredient is rare. It is also non-mutagenic and has a clean track record.

Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces.

A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks.

Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.

One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.

Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

Studies show coating UV filters with dextrin prevents these ingredients from being absorbed. This helps UV ingredients last longer on the skin.

Studies have found adenosine may also help with wound healing.

In skincare products, Adenosine is usually derived from yeast.

You'll likely see this ingredient in "clean" formulations because it's considered a natural alternative to PEGs.

Patch testing at concentration 0.1-1% showed no reactions and this ingredient is considered to be well-tolerated across skin types.

Due to its myristic acid base, this ingredient may not be fungal acne safe.

On the emulsifier side, it keeps your formula smooth and well-mixed by playing peacekeeper for ingredients that don't naturally get along (like oil and water).

Because it has a C12 (lauric acid) fatty acid chain, this ingredient can potentially feed the Malassezia yeast that causes fungal acne.

The Malassezia yeast prefers esters with C11-C24 fatty acids If you're prone to flare-ups, you might want to patch-test or skip this one.

This ingredient is an ester of lauric acid and Polyglycerin-10.

Acrylic acid itself is toxic, but the polymer form (this ingredient) is too large to penetrate skin, making it non-toxic.

Besides fatty acids, avocados also have B vitamins, vitamin K, vitamin C, vitamin E, and potassium.

Kale leaf extract also helps hydrate the skin as a humectant. Kale is rich in omega-3 and omega-6 fatty acids that help soothe and hydrate skin. Studies show Brassica Oleracea Acephala Leaf Extract is effective at calming inflammation and treating inflammatory skin diseases.

Besides Vitamin C, Kale is also rich in vitamin A and vitamin K.

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.

A 2025 review of 18 human studies found that using Ferulic Acid (0.5-1%) daily for one to three months showed improvements in:

As far as allergies go, Ferulic acid is generally well-tolerated but can cause an allergic reaction in very rare cases. It's also worth noting that Ferulic acid is often extracted from plant sources like rice bran or wheat bran, so be sure to path test if you have known grain allergies.

Outside of skincare, researchers are also looking into Ferulic Acid for its potential benefits in areas like diabetes, Alzheimer's, and heart health.

Beet root has many benefits when eaten. More research is needed on applying beetroot in skincare.

Beet Root is used to add pink/red color.

These berries also contain Vitamins A, B, and C.

Studies show the polyphenol content varies depending on region. Lingonberries grown in Alaska and Europe show high antioxidant content, while the lowest antioxidant content is found in eastern Canada.

Vitamins C and E are potent antioxidants and may help with anti-aging. The fatty acids are emollients that help soften and hydrate your skin.

Another potent vitamin found in rosehip is Vitamin A, or retinol. Retinol encourages collagen production in the skin.

Rosehip extract may help with brightening the skin. Several components, such as beta-carotene, are able to reduce pigmentation caused by sun damage.

This ingredient is incredibly gentle and often used to counter more irritating ingredients.

While our skin does have collagen, this ingredient is not used by the skin for anti-aging. Applying collagen topically has not been linked to helping with collagen loss in skin. All the benefits of soluble collagen are related to hydration.

Fun fact: The name "soluble collagen" refers to its ability to dissolve in water.

More research is needed on applying biotin topically. However, taking biotin orally has been shown to help nourish the skin, hair, and nails. They play a role in forming skin-hydrating fatty acids.

Biotin is water-soluble. It can be found in foods such as fish, eggs, dairy, nuts, and meat. Vitamin H stands for "haar" and "haut". These are the German words for hair and skin.

3-O-Ethyl Ascorbic Acid interferes with the process of skin darkening, helping to reduce hyperpigmentation. It also encourages the skin to produce more collagen.

Once applied, 3-O-Ethyl Ascorbic Acid is converted to Vitamin C deeper in the skin's layers. This process is slow but makes this ingredient more tolerable for skin.

The optimum pH range for this ingredient is 4 - 5.5

Studies show SAP has anti-acne and antioxidant benefits. One study found 5% of SAP lotion to be an effective ingredient for treating acne vulgaris. This is because research shows that SAP may help control acne by reducing acne-causing bacteria and slowing the oxidation of skin oils caused by UV exposure.

In addition to acne, vitamin C is important for skin structure. Lab studies suggest SAP may support collagen production in skin cells, making it a great ingredient in anti-aging routines.

Vitamin C has many benefits: it helps reduce redness, improve skin texture, fade the appearance of dark spots, and brighten the skin.

Read more about other types of Vitamin C:

Topical vitamin C has been shown to help neutralize oxidative stress from UV and pollution, helping to improve photoaging and hyperpigmentation when used consistently.

One clinical study found that using 5% topical vitamin C for six months improved signs of photodamaged skin, both on the surface and in the deeper structural layers of the skin.

While vitamin C doesn’t replace sunscreen, studies show it can boost photoprotection when combined with Vitamin E and ferulic acid. These two ingredients help improve stability and protective effects.

The big downside of this ingredient is formulation difficulty. Vitamin C is prone to oxidation and doesn't penetrate the skin unless formulated correctly. Research found that vitamin C absorbs into the skin best at a low pH (< 3.5) with about 20% being the upper limit for effective absorption.

Skin levels can saturate after repeated application; this means your skin won’t keep absorbing more once it’s full of vitamin C. This is why more isn’t always better with vitamin C and why very high concentrations don’t necessarily give extra benefits.

Ascorbic acid generally works well with many skincare ingredients but can be irritating when combined with other active ingredients. Strong oxidizing acne treatments like benzoyl peroxide can reduce the effectiveness of vitamin C if they are used at the same time; they are often recommended for use at different times of day.

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.

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:

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

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.