What does Vitamin C serum have to do with skin aging?

What does Vitamin C serum have to do with skin aging?

To treat and prevent photoaging, dermatologists recommend only five products in this minimal but effective routine. On the list is antioxidant, an essential that protects skin from photodamage caused by free radicals, which in turn prevents photoaging. Vitamin C, being the most studied antioxidant, is the most recommended option. There are a number of vitamin C serums out there and most are questionably unstable or don’t effectively absorb into the skin. Learn why vitamin C is important for our skin health and things to keep in mind when you search for a serum to build into your regimen.

What is vitamin C?

When thinking about vitamin C, you might automatically think about taking supplements or eating citrus fruits to “boost” your immune system. We constantly hear about and know the potential benefits of ingesting vitamin C, but how about the application of it on our skin? And no, this does not mean rubbing a lemon or orange all over your face. (Seriously, don’t.)

Vitamin C is an antioxidant and an essential nutrient necessary for the growth and repair of tissues, but we cannot produce it on our own. Vitamin C is ample and naturally occurring in nature and we take it in through our diet, which can include green leafy vegetables and citrus fruits. Just as our internal bodies need vitamin C, so too do our external bodies. 

We think about taking care of our internal health in terms of what we ingest. However, we sometimes forget that our skin is our largest organ and is constantly exposed to harsh conditions everyday. Daily exposure to UV rays and air pollution damage our skin cells. Vitamin C is the most abundant antioxidant in human skin, which is helpful in preventing skin cell damage. It neutralizes free radicals that may lead to photoaging, while promoting collagen production as well. Collagen requires vitamin C to cross-link and lay down strong supports in your skin.

Oxidative stress causes premature skin aging

Before talking about the role of vitamin C on our skin, we have to discuss the antagonist: free radicals. Our bodies naturally produce free radicals. However, external factors such as pollution can cause an abundance of free radicals, which is something we want to avoid. Our bodies are constantly undergoing a process called oxidation, wherein free radicals are produced, but again, it is something we want to minimize. An imbalance between the free radicals and antioxidants in our bodies leads to oxidative stress. 

Antioxidants are able to make free radicals less reactive. Even so, when there is an imbalance, free radicals can negatively affect our bodies. Oxidative stress can be linked to a number of internal diseases and illnesses, but it can also affect the appearance of our skin.

Free radicals cause damage to the skin by damaging the dermis of the skin. This, in turn, affects skin cells, texture, color, and moisture barrier. Free radicals introduced by our environment can affect collagen development as well. Exposure to light (going out in the sun) also affects the availability of vitamin C in the skin and also can produce reactive oxygen species, or ROS. ROS is related to free radicals and an abundance can be harmful to our cellular DNA, the cell membrane, and cellular proteins, which includes collagen.

How to prevent oxidative stress

There are two things you can do to prevent oxidative stress:

  1. Decrease your formation of free radicals
  2. Increase your levels of antioxidants

The best way to decrease levels of free radicals is to avoid external factors like UV exposure, environmental pollutants, and smoking.

Since vitamin C is an antioxidant, it counteracts the effects that free radicals may have in and on your body by making them less reactive and maintaining balance so oxidative stress does not occur. You may be thinking, “If I am getting vitamin C from my diet, why isn’t it improving the appearance of my skin?” No matter how much vitamin C you may be ingesting, absorption in the gut is limited and vitamin C must be applied directly on the skin to see any external benefits.

Properties of vitamin C and its benefits

Although vitamin C is mostly known for being an antioxidant, it has other properties and benefits. They demonstrate how it’s an excellent option for treating and preventing photoaging.


As described before, vitamin C is an antioxidant that protects against the free radicals from the environment as well as prevents oxidative damage. Additionally, the antioxidant benefits include evening skin tone and promoting collagen production. UV exposure is harmful to our skin and vitamin C has the potential to protect our skin from any precancerous changes that may occur because of UV rays.


Sunscreen does protect against UV rays, but when used in conjunction with vitamin C, UV protection can be optimized. While vitamin C does not absorb UV light, it protects our skin against photoaging by neutralizing free radicals, which is not an effect prevalent in sunscreens. Vitamin C works great on its own, but when used together with vitamin E and ferulic acid, its efficacy as a photoprotective agent and prevention against skin cancer increases up to eight-fold

Collagen synthesis

As we age, our skin inevitably ages with us; however, vitamin C promotes collagen production, which keeps skin from prematurely aging. By increasing collagen synthesis, stabilizing collagen fibers, and decreasing collagen degradation, the physical appearance of skin can be vastly improved. Since vitamin C is acidic, it helps skin cells accelerate the production of collagen and elastin. This prevents sagging skin, improves rough texture, and keeps skin looking hydrated. 


Vitamin C is often labeled as “brightening” and can help reduce the hyperpigmentation in skin. By acting as a depigmenting agent, it inhibits skin’s melanin production, decreases melanin formation, and reduces pigmentation. Vitamin C can help even out uneven skin tone and lighten under eye circles. Even if you are not struggling with acne currently, old acne scars could remain on your skin. Old acne scars can potentially be remedied with vitamin C as it fades that hyperpigmentation. 


Adding vitamin C into your skincare routine can alleviate inflammation on your skin. Along with its attributes as a brightening agent, Vitamin C also acts as an anti-inflammatory, effective in treating acne and healing wounds. Vitamin C is also a preventative to post-inflammatory hyperpigmentation.

Side effects

While there are plenty of benefits to using vitamin C, you should still be wary of side effects that may occur. The side effects of vitamin C often stem from how and with what it is applied with. Vitamin C can irritate the skin if it is applied too high of concentration or if it is mixed with other acids. Some of the irritation that occurs may easily be treated with a moisturizer. Since vitamin C is highly oxidative, yellow discoloration of the skin, hypopigmented hair, and staining of clothes can possibly occur. 

What to look for in a vitamin C serum

Now that you’ve learned all the benefits of this potent antioxidant, you’re ready to address photoaging and incorporate vitamin C into your routine if you haven’t already. Vitamin C in skincare products most often come in the form of a serum. When shopping around for a serum, stability matters and you can look out for this in the product formula and the packaging of the product. 

Product formula

You should be buying a serum that contains L-ascorbic acid, which is very well-researched, potent, and the only biologically active form of vitamin C. The penetration of vitamin C into your skin can be challenging–the top layer of the skin (which is hydrophobic) often deters the unstable molecule (which is hydrophilic) from entering the skin. It is important to utilize forms that are appropriately made and stabilized for maximum efficiency. 

With that being said, vitamin C is very active and reactive, so a concentration between 8-20% and a certain pH of less than 3.5 is necessary to keep it stable. Any variations of vitamin C concentration and pH could affect how it penetrates the skin. On its own, vitamin C may not be fully effective; however, paired with complementing antioxidants, ferulic acid and vitamin E, vitamin C can be more effective and stable. 


Like with any skincare product, vitamin C is not going to be good forever and does have a shelf-life. Vitamin C is extremely unstable and can lose its antioxidant properties when exposed to certain elements. Heat, light, air, and other chemicals can cause vitamin C to oxidize, turn brown, and become useless. When paired with vitamin E, vitamin C can be protected against oxidative damage. Additionally, your vitamin C serum should be kept in an air-tight and opaque bottle in a cool, dark environment. If your vitamin C has turned brown, that means it has oxidized and you should probably get a new vitamin C serum. 

How to use

Just as with any new skincare product, you want to start using vitamin C serums slowly and consistently. The time of day you use vitamin C can also affect its efficacy. Using vitamin C in the morning will help with protecting your skin against harsh UV rays. (Of course, still put on sunscreen.) The following AM routine is recommended:

  1. Cleanser
  2. Vitamin C serum
  3. SPF moisturizer (can be separate products)

There are some products you may want to avoid using in conjunction with vitamin C as it may affect its absorption in the skin. Using vitamin C with benzoyl peroxide can oxidize the vitamin C, making it less effective. 

With all these suggestions in mind, however, listen to your skin. You know your skin the best and it is helpful to test products out first on a small patch of your skin, especially if you have sensitive skin. 

As you nourish your body internally, remember that your external body needs nourishment as well too. Treat your skin well and take the right steps to prevent and remedy the hardships that it faces with Dear Brightly’s derm-tested vitamin C & E + ferulic acid serum, Liquid Cloak.