Vitamin C

Vitamin C

Vitamin C is a trending, yet very effective ingredient to add to any skincare product. Its potent antioxidant properties often make it hard not to add to the skincare routine, but is it for everyone?

History

Early Discoveries

Vitamin C has been recognized for centuries, though not always welcomed in the form of topical applications. Ancient cultures, such as the Egyptians and Greeks, used various forms of vitamin C from natural sources such as citrus fruits for skin health.

Scientific Research

In the mid-20th century, research began to surge for the various benefits of vitamin C. Its role in collagen synthesis and antioxidant properties are tempting enough to gather public attention, including scientists, and dermatologists.

Stability Challenges

Stability was one of the initial challenges with topical vitamin C formulas. Vitamin C is notoriously unstable. Its molecules break down when exposed to light, air, and heat. There had to be further steps to stabilize the vitamin C to ensure its efficacy.

Formulation Innovations

Over the years, skincare companies have developed various formulas to make use of topical vitamin C efficiently. Different forms of vitamin C, such as L-ascorbic acid, ascorbyl palmitate, and magnesium ascorbyl phosphates, have been formulated for skincare products such as serums, creams, and lotions.

Effects & Mechanism of Action

Topical vitamin C, best known as ascorbic acid, is multifaceted and involves various interactions with skin cells. Here’s a breakdown of its primary mechanisms:

Antioxidant Activity

The most well-known function of vitamin C is its antioxidant properties. Vitamin C oxidizes free radicals. These unstable molecules can damage skin cells and contribute to premature aging. Vitamin C helps protect cells from environmental stressors, and damages.

Collagen Synthesis

Vitamin C is essential to produce and synthesize collagen. This structural protein provides strength and elasticity to tissues such as skin, tendons, and blood vessels. Vitamin C is a cofactor for the enzymes that synthesize collagen. These, including prolyl, and lysyl hydroxylases, cannot function adequately to support collagen production.

Wound Healing

Vitamin C plays a crucial role in healing wounds by promoting collagen synthesis and the formation of new tissues to repair damaged skin. Moreover, it improves the function of immune cells involved in the inflammatory response. It’s essential for the healing process.

Protection Against UV Damage

Vitamin C provides some levels of sun protection against UV damage to the skin. It helps neutralize free radicals generated by UV lights, and it oxidizes environmental stressors in the skin cells. Moreover, vitamin C may help repair UV-induced DNA damage and prevent the formation of sunburn cells.

Skin Brightening

Vitamin C has skin-brightening properties. It helps inhibit the production of melanin, the pigment responsible for dark spots and hyperpigmentation. Vitamin C hinders the activity of tyrosinase, an enzyme crucial in melanin synthesis. By hindering these cell functions, it helps maintain even skin tone and minimize dark spots.

Side Effects

Topical vitamin C is generally safe for most individuals, including sensitive skin when used in moderation. However, like any skincare ingredient, it can potentially cause side effects. Generally, this includes photosensitivity, irritation, dryness, or flaking, especially with high concentrations. Some may experience staining or discoloration after using unstable vitamin C.

Synergy

Skincare Ingredient	Synergy with Topical Vitamin C
Vitamin E	Enhances the antioxidant activity of vitamin C.
Ferulic Acid	Increases stability and efficacy of vitamin C.
Hyaluronic Acid	Hydrates the skin, and aids in the skin-plumping effects of vitamin C
Retinoids (Retinol, Retin-A)	Helps in collagen synthesis, and improves skin texture and tone.
Niacinamide (Vitamin B3)	Maintains skin barrier function, and reduces inflammation. Good synergy with vitamin C for skin-brightening.
Alpha Hydroxy Acids (AHAs)	Enhances exfoliation, improves absorption of vitamin C, boosts skin renewal
Beta Hydroxy Acid (Salicylic Acid)	Unclogs pores, reduces inflammation, complements brightening properties of vitamin C.
Peptides	Boosts collagen synthesis, enhances firming effects of vitamin C.
Ceramides	Strengthens skin barrier, improves moisture retention, complements hydration effectsof vitamin C
Antioxidants (Green Tea Extract, Resveratrol)	Enhances overall antioxidant protection, and pairs with vitamin C for UV-damage.

Forms

L-Ascorbic Acid

L-Ascorbic Acid is the purest, and most studied form of vitamin C. It is water-soluble and highly effective in providing antioxidant protection. However, L-Ascorbic Acid is unstable and prone to oxidation. This can reduce its efficacy over time, and trigger skin sensitivity.

Sodium Ascorbyl Phosphate

SAP is a table, water-soluble derivative of vitamin C. It is less irritation, but less studied than L-ascorbic acid. However, it is suitable for sensitive skin, and may be less potent.

Tetrahexyldecyl Ascorbate (THD Ascorbate)

THD Ascorbate is a table, oil-soluble form of vitamin C that easily penetrates the skin lipids. It's especially useful for oily and acne-prone skin for its oil-soluble properties. However, it may irritate sensitive skin, especially in high concentrations.

Optimal pH Levels

Vitamin C formulations typically work well within the acidic range, preferably between 3.5 and 4.0. This acidic pH range is suitable for its stability and efficacy, particularly for the most common and well-studied form of vitamin C skincare: L-ascorbic acid.

Counter Effects

Substance	Reason for Avoidance
Benzoyl Peroxide	May oxidize vitamin C.
Copper Peptides	Reducing its stability and efficacy.
Retinol (and Retinoids)	Both retinol and vitamin C can be irritating when used together, especially for sensitive skin.
Alpha Hydroxy Acids (AHAs)	May increase skin sensitivity when combined with vitamin C.
Beta Hydroxy Acid (Salicylic Acid)	Similar to AHAs, salicylic acid may increase skin sensitivity.
Niacinamide (Vitamin B3)	Some studies suggest that high concentrations of niacinamide can react with vitamin C, potentially forming flushing.

Skin Type

Normal Skin

Vitamin C can help maintain overall skin health and appearance by protecting it with its antioxidant properties against environmental stressors. Vitamin C is also well-known for its benefits on collagen synthesis. This improves firmness and brightens the skin.

Dry Skin

Vitamin C is also beneficial for dry skin. It helps to hydrate and moisturize the skin. It also promotes collagen for improved skin elasticity. Its antioxidant properties also help protect against free radical damage.

Oily Skin

Vitamin C also possesses the ability to regulate sebum production and minimize the appearance of pores. It also helps to reduce inflammation and redness that often come with acne. Moreover, it slows down sebum oxidation, which often triggers skin darkening.

Combination Skin

Vitamin C is a must for combination skin as it can address multiple skin concerns. Combination skin is known to have dry, and oily areas with uneven skin tone. It helps balance oil production, hydrate dry areas, and improve overall skin texture.

Sensitive Skin

Vitamin C is generally well-tolerated by sensitive skin types, especially when formulated in gentle, non-irritating formulations. However, individuals with sensitive skin should patch-test new products and start with lower concentrations of vitamin C to minimize the risk of irritation.

Sensitive skin generally tolerates vitamin C, especially its formula aims to work gently without irritation. However, a patch test should be performed before introducing higher concentrations of vitamin C to minimize the risk of irritation.

Aging Skin

Aging skin can extensively benefit from vitamin C. Its collagen-stimulating properties help reduce the appearance of fine lines and wrinkles. As a result, it improves skin firmness and elasticity for mature skin. Its antioxidant properties also help protect against UV lights and environmental stressors.

Alternatives

Concern	Alternatives
Anti-Aging	Retinoids (Retinol, Retinaldehyde), Peptides, Niacinamide (Vitamin B3), Bakuchiol, Growth Factors
Hyperpigmentation	Hydroquinone, Alpha Arbutin, Kojic Acid, Licorice Extract, Azelaic Acid, Tranexamic Acid
Sun Damage	Antioxidants (Vitamin E, Green Tea Extract, Resveratrol), Niacinamide (Vitamin B3), Coenzyme Q10, Ferulic Acid
Dullness	Alpha Hydroxy Acids (AHAs), Beta Hydroxy Acid (Salicylic Acid), Retinoids, Enzymes (Papaya, Pineapple), Ginseng Extract
Dryness/Dehydration	Hyaluronic Acid, Glycerin, Ceramides, Squalane, Fatty Acids (Omega-3, Omega-6), Panthenol (Vitamin B5)
Acne/Blemishes	Salicylic Acid, Benzoyl Peroxide, Tea Tree Oil, Azelaic Acid, Niacinamide (Vitamin B3), Retinoids
Sensitive Skin	Aloe Vera, Centella Asiatica (Cica), Chamomile Extract, Green Tea Extract, Colloidal Oatmeal
Uneven Texture	Alpha Hydroxy Acids (Glycolic Acid, Lactic Acid), Beta Hydroxy Acid (Salicylic Acid), Retinoids, Enzymes (Papaya, Pineapple), Peptides