Unlock the Secret to Radiant Skin with Vitamin C

We can all appreciate a healthy, smooth and radiant skin with even tone. Summer is the season when our facial and neck skin receives the highest amount of UV exposure and having a skincare routine promoting health is of paramount importance.

Summer is the season when most of the pigmented spots appear on our skin. I can say from personal experience that these can be annoying and very challenging to treat.

Hyperpigmentation conditions affecting the face and neck can have a significant impact on the quality of life of many people. Vitamin C containing products have been used worldwide in the treatment of these conditions. That’s why today I would like to talk about the effects of Vitamin C on our skin. So, lets dive into some research.

Effects of Vitamin C on the skin

Vitamin C (ascorbic acid) has an important role in regulating the health of our skin, stimulating the differentiation of epithelial skin cells while at the same time reducing the production of melanin. As a result we get antioxidative protection against solar-related skin damage. We can only source vitamin C through our diet which means our daily dietary choices play a roll in maintaining our skin’s integrity and health. Vitamin C also helps in preventing and treating some of the common skin conditions.

There is a strong connection between vitamin C and skin aging, pigmentation and control of skin conditions.

Vitamin C has effect on skin cancer through it’s antioxidative properties. Literature sources suggest that topical application of vitamin C has clinical effects compared to oral intake.

Vitamin C plays an important role in the different skin layers and it helps the skin to carry out some of its key functions like preventative, protective, healing and rejuvenative. It clinically improves some dermatological conditions. The most evident antioxidative effect is seen in the epidermis which primarily consists of keratinocytes and melanocytes. The underlying dermal layer gives the skin its elasticity and strength and houses structures like neurovascular bundles, glands and collagen fibres.

The concentration of ascorbic acid is over 400% higher in the epidermis than the dermis. There is a higher concentration in the deeper layers of the epidermis, possibly because the superficial layers are constantly exposed to the effects of the external environment.

Chronologically aged and photo-aged skin contains lower amounts of vitamin C.

Vitamin C in cosmeceuticals

The modern pharmaceutical industry has developed a large variety of vitamin C containing topical formulations in regards to their purity and efficacy which are predominantly creams, gels and serums.

One of the most desired effects of vitamin C is in reducing facial dyschromia.

Skin hyperpigmentation disorders (melasma, post-inflammatory hyperpigmentation, solar lentigines, and maturational hyperpigmentation) have a significant negative emotional impact on the lives of many people as they can be very difficult to treat.

The treatments for hyperpigmentation can be very expensive and thus many people prefer referring to over-the-counter (OTC) options. This, in turn, drives demand for OTC skincare products or cosmeceuticals aimed to enhance skin brightness and reduce hyperpigmentation.

This is a fast growing industry that is both poorly regulated and non-standaridised and cosmeceuticals are able to make claims without evidence or data to support these claims.

A resent study compared different highly rated vitamin C products available on Amazon and Sephora. Consumers howed no preference for the vitamin C derivates present in these products.

Consumers prioritized efficacy and cosmetic elegance when purchasing vitamin C products.

Regardless of the derivatives present, it appears that consumers would rank products that are deemed more elegant over equivalent derivatives that have less preferred texture and formulation. I can say I am GUILTY of this. A product with an eyecatching and appealing package can sell much better and quicker than a simpler looking but equally effective product.

It is very important for dermatologists to be up to date and remain aware of, OTC skincare products to advice on best treatment practices and potential adverse effects due to the immense market variety.

There has been a growing consumer interest in vitamin C serums which is obvious by both rise in sales and an increase in Google searches for these products.

There are several vitamin C derivates available on the market. All products must be formulated carefully to allow efficient penetration into the skin and prevent its brakedown.

We know that ascorbic acid has one of the highest bioavailability of all forms of vitamin C, however it is not the most effective one due to its hydrophilicity. This makes penetration of the stratum corneum less efficient than other derivates.

Furthermore, ascorbic acid in high concentrations can be irritating to those with sensitive skin. Many products currently on the market use other derivates of vitamin C, including L-ascorbic acid, magnesium ascorbyl phosphate, 3-0-ethyl ascorbic acid and tetrahexyldecyl ascorbate.

The different derivates vary in terms of their stability and their ability to prevent malanogenesis.

While all products may be marketed for the same use and contain many of the same active ingredients, their effects can be greatly altered by the additional compounds in the formula.

Methods for delivering vitamin C to the skin

The most efficient mechanism for delivering vitamin C to the skin has not been ascertained as of yet.

A systematic review on microneedling efficacy for treatment of melasma found that the combination of vitamin C and microneedling led to a 3.7% decrease in the Melasma Area Severity Index (MASI). By making small puncture wounds in the skin, microneedling allows vitamin C to bypass the stratum corneum and therefore helps increase the efficacy of the compound. However, granuloma formation can be a rare adverse event as a result of microneedling with vitamin C.

This highlights the need for thorough assessment of the compound formulation as well as any additives that may be present in serums used along with microneedling treatment, to offset the rate of this and other adverse effects.

Laser technology has been used for transdermal drug delivery. It has been suggested that lasers can increase the efficacy of vitamin C delivery by disrupting the skin’s stratum corneum to allow for better penetration of compounds.

Vitamin C and hyperpigmentation

Vitamin C is one of the most commonly used OTCs for hyperpigmentation.

It can be found in variety of forms and at a lower price point than alternative treatment options. This makes it easily accessible for many consumers. Nevertheless, given the multitude of options, it can be difficult to distinguish between products and identify which will be most effective for the specific concerns.

Lack of vitamin C in skin and skin aging changes

Lack of vitamin C in the epidermis leads to peroxidative damage of the skin cells. In addition the epidermis is constantly exposed to ultraviolet radiation, which further accelerates aging because of reactive oxygen species (ROS). In the underlying dermis, deficiencies in vitamin C can cause damage to the connective tissue also because of peroxidative stress.

It is uncertain if diet rich in vitamin C has better long term benefits to the skin. The lack of ascorbic acid increases the oxidative stress and more so in presence of UV exposure, thus resulting in skin aging.

Skin changes in chronological aging include fine wrinkling, reduced elasticity, loss of volume and deepening of the expression lines. There is further decline in the recoiling and elastic capacity of the skin which is due to reduced fibrovascular support structure and reduction in collagen and elastin.

Aging leads to dry skin because of further decline in glycosaminoglycans which help in retaining moisture within the dermis. This leads to skin fragility and easy bruising, more so in sun-exposed areas such as face and neck.

The epidermis gradually decreases its barrier function and the ability to repair following trauma. However the dermis suffers greater age-related changes compared to epidermis. Antioxidant capacity, immune regulation and melanin production appear to also be impaired in aged skin.

Regular use of vitamin C containing supplements (orally or topically) has the potential to reverse skin aging by regenerating the elastic fibre system and collagen within the dermis.

Vitamin C decreases the production of melanin which is a desired effect in treatment of skin hyperpigmentation in conditions such as melasma and post-inflammatory hyperpigmentation. Other agents that have such potential are hydroquinone, glutathione, azelaic acid, niacinamide, glycolic acid, kojic acid, vitamin E, retinoids and cannabidiol.

Skin lightening treatments are becoming increasingly popular in the beauty industry.

Two of the most common reasons being treatment of widespread forms of non-segmental vitiligo and for those who find light skin complexion to be more appealing.

A combination of vitamin C and glutathione has been used as intravenous infusion for eradication of melanin pigmentation.

Vitamin C in diet

In terms of its nutritional value, vitamin C is water soluble, heat sensitive and easily oxidised. Keeping vitamin C containing products refrigerated retains nutritional properties.

Fruits and vegetables should be eaten unpeeled if possible and not to be cut into small pieces to avoid exposing cells to oxidation.

We should avoid soaking fruits and vegetables in water and cooking with excessive amounts water or cooking under poorly fitting pot lid.

The best sources of vitamin C include citrus fruit, orange juice, spinach, cabbage, green pepper, Brussels sprouts, turnips, guavas, pineapples, sweet melons, fresh strawberries and correctly prepared potatoes. Smaller quantities of it can be found in peaches, pears, apples, bananas and blueberries.

Diet with adequate presence of vitamin C promotes the barrier functions of the skin, improves dry skin and smooth skin surface. The concentration of ascorbic acid in keratinocytes can double upon supplementation with certain foods or 3 g/day supplementation for 6 weeks, a dosage which is higher than the recommended daily intake and would achieve plasma saturation and likely also tissue saturation.

Nutritional deficiency of vitamin C can clinically as scurvy. As ascorbic acid has a central role in the protective functions of the skin, its deficiency results in skin fragility, perifollicular petechiae, ecchymosis (easy bruising), gingivitis and poor wound healing.

Keratinocytes play a key role in skin barrier function. They prevent water loss and microbial invasion in the deeper layers of the skin. Vitamin C has a central role in aiding this process.

Some people with atopic dermatitis have been reported to also suffer from food allergies. There is an link between vitamin C deficiency and atopic eczema, resulting from certain food avoidance and precautionary food consumption.

Vitamin C can also stimulate ceramide (natural skin lipids) production within keratinocytes and improve the overall epidermal barrier function.

In people with more marked symptoms of atopic dermatitis, the levels of vitamin C and ceremide are very much reduced. This is a positive correlation between atopic dermatitis, vitamin C and natural skin lipids.

Vitamin C effect on cancer cells and wound healing

Ascorbic acid has toxic effect on tumour cells which can be attributed to the induction of oxidative stress in tumour cells. Vitamin C can also increase 5-hydroxymethylcytosine content in melanoma, which reduces tumour growth.

Furthermore, cancer patients have been shown to have very low reserves of ascorbic acid, which is essential for the structural integrity of the intercellular matrix. Degradation of the extracellular matrix correlates with the aggressiveness of tumour growth and invasiveness of the cancer.

The combination of vitamin E and vitamin C reduces the incidence of oxidative stress-induced tumours and their antioxidant effects are much better compared to the use of vitamin C alone. The effects are even greater when ferulic acid and selenium are added.

Combination of vitamin A, vitamin C and zinc leads to quicker recovery in wound healing.

Vitamin C is beneficial in wound healing by stabilising collagen. It prevents collagen’s degradation and inhibits the enzymes responsible for collagen damage in UV-irradiated skin. Vitamin C also regulates the production of elastin in fibroblasts and has increased turnover in wound sites thus topical use and oral intake has been beneficial. Additionally, a combination of vitamin C and vitamin E improve the rate of wound healing in individuals and skin burns.

Transcutaneous penetration and topical application of vitamin C

Vitamin C is a charged molecule that is repelled by the physical barrier of the terminally differentiated epidermal cells. Transcutaneous penetration occurs when the pH levels are below 4. In addition, absorptive capacity also depends on the pH of the formulation that vitamin C is placed in.

Vitamin C can be delivered to the epidermal layer by topical application although the efficacy of this is dependent on the formulation of the cream or serum used on the skin. This entails gentle rubbing of the vitamin, and in this regard, available literature leans more towards the cosmetic value of topical applications containing this vitamin, predominantly in anti-aging, treatment of hyperpigmentation and skin lightening.

The cosmetic industry is focused on the development of ascorbic acid derivates for the purpose of topical application. Such derivates need to ensure stabilisation of the molecule from oxidation and overcome the significant challenge of skin penetration. Furthermore, these derivates must be converted to ascorbic acid in vivo to be effective.

Topical vitamin C is available on the market as a variety of creams, serums and transdermal patches. The serums are the only ones that contain active forms of this vitamin in an almost colorless form. It is very unstable and, on exposure to light, gets oxidised to dehydroascorbic acid, which imparts a yellow colour. Minor adverse reactions include a yellowish discolouration of the skin, hypopigmented hair and staining of clothes. Once applied, it cannot be fully washed or wiped off the skin. Rarely, stringing, erythema and dryness are observed after topical usage. These can be easily be treated using a moisturiser.

Vitamin C is an affordable and available over-the-counter vitamin with low toxicity potential.

Vitamin C oral supplements

Oral intake depends on the objective because this vitamin is associated with wide range of medicinal benefits. The duration, frequency and dosing largely depend on the desired outcome.

With adequate dietary intake, oral supplementation has been found to be of limited value.

Low doses contained within multivitamin supplementation tablet can be considered as part of health supplementation and optimised immunity.

The recommended daily oral amount for vitamin C is 75 mg a day for women and 90 mg a day for men. During pregnancy, 120 mg per day is recommended because of higher demands of the gestational period.

Intravenous infusion of vitamin C

Intravenous infusion is favoured when used in combination with glutathione when aiming to universally lighten the skin for those lured by cosmetic appeal. The appeal may be for those who perceive darker skin as unsatisfactory or those with widespread non-segmental vitiligo. This appeal is predominantly seen among women. The IV infusions of vitamin C has been a hot topic in recent years, especially in Korean beauty regimens so I will discuss it in a separate post.

Conclusion

In conclusion, vitamin C has many undeniable beneficial uses in medicine although further research is needed with regard to dosages for different indications, frequency of use, duration of use, ideal formulation and in-depth monitoring of ideal cutaneous concentrations in relation to response to therapy or supplementation.

References:

Makhakhe L. The role of vitamin C on the skin. S Afr Fam Pract (2004). 2025 Jul 14;67(1):e1-e7. doi: 10.4102/safp.v67i1.6098. PMID: 40776734; PMCID: PMC12339815.

Lazar M, Rajanala S, De La Garza H, Vashi N. Consumer Preferences of Topical Vitamin C Products: A Comparative Study. Cureus. 2023 Sep 17;15(9):e45414. doi: 10.7759/cureus.45414. PMID: 37854746; PMCID: PMC10581507.