Pure Vitamin C (L-ascorbic acid) is one of the most powerful skincare ingredients for improving the appearance of fine lines and wrinkles, fading hyperpigmentation, protection against photo-aging and pollution AND treating acne scarring! It’s one of the most thoroughly researched skincare ingredients and dermatologists definitely agree that it is one of the most effective ingredients to include in your skincare routine.
I’ve written an article on the benefits that vitamin C has on the skin (you can check it our here), but today I’d like to take a closer look at the Korean vitamin C serums currently available and which ones I think would be most effective.
The Importance Of Vitamin C In The Body
All animals naturally use vitamin C to protect themselves from oxidative damage – as well as to synthesize collagen, heal wounds and perform many other important functions throughout the entire body. In fact, vitamin C is an essential vitamin that animals simply cannot survive without (for example, a lack of vitamin C in most animals results in scurvy).
Some animals (such as ruminants) can synthesize vitamin C from monosaccharides within the body. However, humans (and other primates), guinea pigs, invertebrates, some insects, fish, bats and birds cannot synthesize vitamin C (as they lack an important enzyme called L-gluconolactone oxidase).
Vitamin C is therefore an essential part of our diet, and it is absorbed in our small intestines when we eat foods such as citrus fruits and green leafy vegetables.
The Role Of Vitamin C In The Skin
Just as vitamin C is necessary to perform important biological functions throughout the body, it is also an important ingredient to include in our skincare routine. This is because our skin requires vitamin C to synthesize collagen and to inhibit the overproduction of elastin following UV exposure. As you might already know, collagen and elastin are two important fibrous components of the dermal layer of our skin (known as the dermis). Together, they maintain the supportive structure of our skin – giving it both firmness and elasticity.
Unfortunately, as we age, our skin becomes thinner and more fragile (because the collagen and elastin structures begin to break down). Lifestyle and genetics are contributing factors in the rate at which these fibrous proteins break down, however, it’s typically said that our skin produces about 1 percent less collagen each year after the age of 20. I did the math, and that means that my skin is already producing 15% less collagen then when I was 20 years old!
How Vitamin C Helps To Prevent Skin Aging
Although skin aging is a natural process that we can’t stop from happening, using antioxidant ingredients such as vitamin C in our daily skincare routine can help slow this process down.
Research has shown that L-ascorbic acid easily penetrates into the dermis layer of our skin (where it’s needed) due to its small molecular size and water-solubility.
Studies have found that topically applied L-ascorbic acid at concentrations between 5 and 15% has a skin anti-aging effect by:
- Increasing the production of collagen types I and III
- Preventing the inactivation of enzymes which stabilize the three-dimensional structure of collagen
- Inhibiting the enzyme collagenase 1 (which is one of the enzymes that break the peptide bonds in collagen)
- Neutralizing and removing oxidants found in environmental pollutants
- Neutralizing and removing oxidants found after exposure to ultraviolet radiation (thereby preventing photo-aging)
In addition, vitamin C has also been shown to prevent hyperpigmentation (starting at concentrations of 10%) by inhibiting the enzyme tyrosinase (which is necessary for the synthesis of melanin). However, although vitamin C has been shown to prevent hyperpigmentation from occurring – it hasn’t been shown that it can treat hyperpigmentation that already exists on the skin.
Does My Skin Already Contain Vitamin C?
Yes, our skin already contains vitamin C – which as I mentioned is absorbed in the small intestine from fruits and vegetables that we eat. Although no studies have been conducted on the relationship between the levels of vitamin C in our diet and the aging of our skin, more generalized nutritional studies have found that diets higher in antioxidants are associated with improved measures of skin elasticity, facial wrinkling, roughness and color.
This suggests that eating a diet rich in fruits and vegetables (or antioxidant supplementation) can indeed benefit skin health. However, it’s difficult to determine which active component in the fruit and vegetables is responsible for the observed benefit to the skin. The observed effect from these studies is likely to be multifactorial, and not only a result of vitamin C in the diet.
There is also a question of how stable vitamin C serums are (since ascorbic acid is an highly unstable compound and easily oxidizes when exposed to oxygen, light or heat). It’s therefore extremely important to know what to look for in a vitamin C serum (which I’ve written about here).
So Should You Buy A Vitamin C Serum Or Is It A Waste Of Money?
If you have a healthy diet, full of fruits and vegetables that are high in antioxidants, then your skin should contain enough vitamin C to function the same way that a topical vitamin C serum would function. So, is your money better spent on other skincare products?
I spent a lot of time digging a little deeper into this, and what I found was many testimonials from people in their 50’s and 60’s who saw huge improvements in their skin when using a vitamin C serum long term (generally longer than 3 months). I also found the same age group commenting that their skin became easily pigmented with dark spots when they stopped using a vitamin C serum.
This could be explained by the evidence that as we age, the level of vitamin C in our skin declines in both the dermis and epidermis and also the fact that sunscreens only block 55% of the free radicals produced by UV exposure! Additionally, pollutants such as smoke and exhaust fumes also lower vitamin C content (especially in the epidermis). We all know that smoking cigarettes causes our skin to age faster. One of the reasons is that smokers have been shown to have depleted vitamin C levels compared with non-smokers.
So, although it’s a hot debate whether a vitamin C serum is necessary if you’re already getting enough vitamin C through dietary intake, I do think that people with mature skin could benefit from the UV-protective effects of a quality vitamin C serum (especially if you get excessive sun exposure like me here, in Australia).
The 5 Best Korean Vitamin C Serums
In my previous posts about vitamin C, I talked about how much I’m loving the Timeless 20% Vitamin C+E+Ferulic Acid Serum, which is a Western brand and not a Korean brand. I did hours upon hours of research before deciding to go with this vitamin C serum. The reasons I like it so much is because:
- It contains pure vitamin C (L-ascorbic acid – which is the only active form of vitamin C)
- It contains an optimal concentration of vitamin C (research has shown that a concentration of 20% is most effective at preventing hyperpigmentation)
- It contains vitamin E (vitamin C is particularly effective at reducing oxidative damage to the skin when it is used in conjunction with vitamin E)
- It contains ferulic acid (which also works as a potent antioxidant, but also improves the stability of vitamin C and E)
- It comes in a dark glass dropper bottle (which ensures a slower rate of oxidization, as less light can penetrate the product)
However, I really feel like I’ve neglected the Korean vitamin C serums in the posts I’ve written so far. Plus, I’d really like to try one myself, so I thought it was time to learn a little bit more about what different Korean vitamin C serums are available. And as always, I will share what I find with you!
So, here are the what I think are the best Korean vitamin C serums currently on the market:
# 1 COSRX Triple C Lightning Liquid
Full ingredients list: Aronia Melanocarpa fruit extract (Black Chokeberry), Ascorbic acid (Vitamin C), Butylene glycol, Sodium lactate, Licorice root extract, 1,2- Hexanediol, Pullulan, Sodium hyaluronate, Cassia obtusifolia seed extract, Allantoin.
What form and concentration of vitamin C does this serum contain? 20.5% L-ascorbic acid.
Does it contain vitamin E or ferulic acid? No.
Other beneficial ingredients: Contains 72% black chokeberry (which stabilizes the high concentration of vitamin C), butylene glycol, allantoin and sodium hyaluronate (humectants which help to hydrate the skin), licorice root extract (which is soothing and helps to fade hyperpigmentation), Cassia obtusifolia seed extract (which is an anti-inflammatory, antioxidant and anti-redness ingredient).
Pros & Cons: I love products with minimal ingredient lists, which this serum does so well with only 10 ingredients! I like that it is fragrance and essential oil free and that it contains some great humectants and soothing ingredients. I know packaging shouldn’t affect which products you buy, but I really like how pretty this dark blue dropper bottle is.
How is the product packaged? This vitamin C serum comes in a dark blue glass dropper bottle to help prevent it from oxidizing.
What is the shelf life of this serum? The shelf life of this serum is about 3 months as it contains pure vitamin C. The shelf life can be extended a little if the serum is kept refrigerated.
Available at: SokoGlam only (as it is a special collaboration between COSRX and SokoGlam)
#2 PURITO Pure Vitamin C Serum
Full ingredients list: Sodium Hyaluronate (84%), Ascorbic Acid (10%), 1,2-Hexanediol, Niacinamide, Arginine, Human Oligopeptide-1, Hydrolyzed Collagen, Nelumbo Nucifera (Sacred Lotus) Flower Extract, Magnolia Liliflora Bud Extract, Lilium Tigrinum (Lilium Lancifolium) Extract, Paeonia Officinalis Root Extract, Tuber Melanosporum Extract, Pyrus Malus (Apple) Fruit Extract, Red Ginseng Extract, Sodium Polyacrylate, Adenosine, Disodium EDTA.
What form and concentration of vitamin C does this serum contain? 10% L-ascorbic acid.
Does it contain vitamin E or ferulic acid? No.
Other Beneficial Ingredients: Contains 84% sodium hyaluronate (for skin hydration); niacinamide (AKA vitamin B3 for skin brightening and decreasing appearance of large pores as well as fine lines and wrinkles); arginine (an amino acid that helps to strengthen and repair the skin’s barrier); oligopeptide-1 (a peptide which increases the rate of healing and renewal of the skin, as well as slows the thinning of aging skin); hydrolyzed collagen (which improves skin dryness and reduces flakiness); ginseng extract (which is a powerful anti-aging ingredient that’s been used in traditional Chinese medicine for thousands of years); adenosine (which has anti-aging, skin soothing and skin restoration properties); and many botanical extracts (including sacred lotus flower extract, which has been shown to have photoprotective effects against UVB exposure).
Pros & Cons: All PURITO products are vegan friendly and cruelty-free. They are also all free of fragrances and essential oils, which can be sensitizing for some people. This serum is a good starting point for vitamin C as the concentration is low enough to not cause irritation, but still high enough to be effective. I also like that this serum contains so much sodium hyaluronate (for hydration) and some great anti-aging ingredients.
How is the product packaged? This vitamin C serum comes in a dark brown plastic pump bottle.
What is the shelf life of this serum? PURITO suggests using this serum within three months of opening. The brand also recommends keeping this serum refrigerated.
#3 Klairs Freshly Juiced Vitamin C Drop
Full ingredients list: Water, Propylene Glycol, Ascorbic Acid, Hydroxyethylcellulose, Centella Asiatica Extract, Citrus Junos Fruit Extract , Illicium Verum (Anise) Fruit Extract, Citrus Paradisi (Grapefruit) Fruit Extract, Nelumbium Speciosum Flower Extract, Paeonia Suffruticosa Root Extract , Scutellaria Baicalensis Root Extract, Polysorbate60, Brassica Oleracea Italica (Broccoli) Extract, Chaenomeles Sinensis Fruit Extract, Orange Oil Brazil, Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Disodium EDTA, Lavandula Angustifolia (Lavender) Oil , Camellia Sinensis Callus Culture Extract, Larix Europaea Wood Extract, Chrysanthellum Indicum Extract, Rheum Palmatum Root Extract, Asarum Sieboldi Root Extract, Quercus Mongolia Leaf Extract, Persicaria Hydropiper Extract, Corydalis Turtschaninovii Root Extract, Coptis Chinensis Root Extract, Magnolia Obovata Bark Extract, Lysine HCL, Proline, Sodium Ascorbyl Phosphate, Acetyl Methionine, Theanine, Lecithin, Acetyl Glutamine, SH-Oligopeptide-1, SH-Oligopeptide-2, SH-Polypeptide-1, SH-Polypeptide-9, SH-Polypeptide-11, Bacillus/Soybean/Folic Acid Ferment Extract, Sodium Hyaluronate, Caprylyl Glycol , Butylene Glycol, 1,2-Hexanediol.
What form and concentration of vitamin C does this serum contain? 5% L-ascorbic acid as well as an unknown amount of sodium ascorbyl phosphate (a vitamin C derivative which is gentler on the skin than L-ascorbic acid).
Does it contain vitamin E or ferulic acid? No.
Other Beneficial Ingredients: This serum contains soothing ingredients such as Centella asiatica extract and Scutellaria baicalensis root extract; hydrating ingredients such as sodium hyaluronate and butylene glycol; various herbal ingredients (many of them being herbs used in traditional Chinese medicine) and various oligopeptides (which increase the rate of healing and renewal of the skin) and polypeptides (which smooth fine lines, increase collagen production and decrease the appearance of pores).
Pros & Cons: This serum is said to be suitable for those with sensitive skin who would like to include a vitamin C serum in their routine (as it only contains 5% ascorbic acid). The downside of this serum is that it contains some essential oils (orange oil and lavender oil) as well as plant extracts that have fragrant components (such as anise fruit extract), which can be extremely sensitizing and can even result in contact dermatitis.
How is the product packaged? This vitamin C serum is packaged in a clear and plastic dropper bottle. However, Klairs does say that this serum has been formulated in a way to make it more stable and not be as prone to oxidation from UV light.
What is the shelf life of this serum? Klairs says that their vitamin C serum has a shelf like of about 2 years!
Available at: SokoGlam
#4 By Wishtrend Pure Vitamin C 21.5% Advanced Serum
Full ingredients list: Hippophae Rhamnoides Water, Ascorbic Acid, Sodium Lactate, 1,2-Hexanediol, Sodium Hyaluronate, Panthenol, Cassia Obtusifolia Seed Extract, Allantoin, Xanthan Gum, Ethyl Hexanediol.
What form and concentration of vitamin C does this serum contain? 21.5% L-ascorbic acid.
Does it contain vitamin E or ferulic acid? No.
Other Beneficial Ingredients: This serum contains 70% Hippophae rhamnoides (sea buckthorn) water, which has been shown to improve skin hydration, trans-epidermal water loss and skin barrier function when used long term. Sea buckthorn is also known to comprise vitamin C and E and many other beneficial compounds (including omega fatty acids and flavonoids). This vitamin C serum also contains sodium hyaluronate and allantoin for extra skin hydration, as well as panthenol (which is another humectant that reaches into the deepest layers of the skin and also has anti-inflammatory properties).
Pros & Cons: This is a potent and effective vitamin C serum (as it contains 21.5% L-ascorbic acid) with a minimal ingredients list (only 10 ingredients!). It contains no artificial fragrance or essential oils.
How is the product packaged? This serum comes in a dark brown glass dropper bottle. The bottle actually comes sealed with a screw top lid (with the dropper packaged separately) to prevent any oxidation from occurring before the product reaches you.
What is the shelf life of this serum? By Wishtrend advises that their vitamin C serum has a shelf life of about 6 months once opened and that it should be kept refrigerated.
Available at: Yesstyle
#5 It’S SKIN Power 10 Formula VC Effector
Full ingredients list: Water, Butylene Glycol, Glycerin, Polyglutamic Acid, Ascorbyl Tetra-Isopalmitate, PEG-60 Hydrogenated Castor Oil, Camellia Sinensis Leaf Extract, Dipropylene Glycol, Ethyl Hexanediol, Ethylhexylglycerin, Carbomer, Triethanolamine, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Disodium EDTA, Fragrance
What form and concentration of vitamin C does this serum contain? This serum contains ascorbyl tetra-isopalmitate, which is an oil-soluble vitamin C derivative. Research (in vitro studies only) has shown that ascorbyl tetra-isopalmitate has a higher rate of conversion to ascorbic acid within the skin when compared to other vitamin C derivatives. It also penetrates both the epidermis (the uppermost layer of the skin) and the dermis (the deepest layer of the skin). I wasn’t able to find any information regarding the concentration of ascorbyl tetra-isopalmitate in this serum.
Does it contain vitamin E or ferulic acid? No.
Other Beneficial Ingredients: This vitamin C serum contains 3 humectants for skin hydration (butylene glycol, glycerin, and polyglutamic acid). Glycerin is one of the most effective humectants used in skincare products and it’s actually naturally present in our skin as part of the natural moisturizing factor. Another beneficial ingredient in this serum is green tea leaf extract, which is high in polyphenols (compounds with powerful antioxidant and skin-soothing properties).
Pros & Cons: This serum doesn’t contain pure vitamin C (L-ascorbic acid). Instead, the vitamin C derivative in this serum must first be converted to ascorbic acid in our skin. However, this serum would be suitable to people who’s skin is too sensitive for L-ascorbic acid skin as vitamin C derivatives are gentler on the skin. A big plus is that this serum is super affordable compared to other vitamin C serums. The only downside to me is that it contains fragrance (although no essential oils, which can be much more irritating than synthetic fragrance).
How is the product packaged? This vitamin C serum comes in a light yellow-colored glass bottle. However, the vitamin C derivative it contains is extremely stable and doesn’t oxidize the same way that L-ascorbic acid does when in exposed to UV light.
What is the shelf life of this serum? The shelf life of this serum is much longer than vitamin C serums containing L-ascorbic acid. It’S SKIN says that their VC Effector Serum has a shelf life of 18 months once opened.
Available at: Jolse
Vitamin C is a fantastic ingredient to include in your skincare routine if you have mature skin (and would like to address fine lines and wrinkles as well as hyperpigmentation), or if you want extra protection against UV light exposure.
Western vitamin C serums (such as those by the brands Timeless and Skinceuticals) are likely more potent than Korean vitamin C serums. This is because they contain higher concentrations of L-ascorbic acid as well as other antioxidants such as vitamin E and ferulic acid (which have been shown to increase the effectiveness of vitamin C).
However, there are some fantastic Korean vitamin C serums available, and some of them are actually more suitable for those with sensitive skin or those only just introducing vitamin C into their skincare routine (compared to Western options). Many Korean vitamin C serums are also full of other beneficial ingredients including humectants and soothing ingredients.