We're guessing there is a good chance you've heard vitamin C recommended as a must-have ingredient in your skincare routine. But if you're wondering why vitamin C is good for skin, we've got you covered with an overview of this beneficial antioxidant.
Vitamin C 101
Vitamin C has long been recognized as beneficial to our general health but it has important benefits that are specific to our skin. As a potent antioxidant, it helps to neutralize free radicals that are caused by oxidative stress in the body and threaten to damage our cells. (Oxidative stress can occur due to natural factors inside the body, as well as external factors, such as exposure to UV rays, cigarette smoke, air pollution, and more.) Given that free radicals contribute to the onset of certain diseases and encourage the characteristics associated with skin aging, the antioxidant benefits of vitamin C alone make it an attractive addition to your skincare regimen. However, there's more. Vitamin C also helps to boost collagen production and decreases its degradation - helping skin to appear firmer and plumper, and interrupts melanin synthesis, giving it the ability to reduce discoloration in hyperpigmented areas of skin and promote skin brightening. Research also suggests that vitamin C may encourage the skin's ability to protect itself from moisture loss.
Thus, you can look at vitamin C as packing a four-way punch:
- Vitamin C can help protect skin from signs of aging by fighting free radicals
- It has anti-aging qualities, allowing it to diminish the appearance of fine lines and wrinkles by boosting collagen production
- It brightens and evens out skin tone by addressing hyperpigmentation (dark spots) that is often caused by sun exposure
- It helps to minimize the potential for dryness
It's quite an impressive list of benefits from one ingredient and makes a pretty convincing argument for the regular use of vitamin C products in your skincare regimen!
Getting Vitamin C to the Skin
While we often think of vitamins as a consumable tablet, in skincare applications, topical vitamin C is typically used. The skin certainly benefits from a vitamin C supplement (and an antioxidant-rich diet that includes lots of fruits and vegetables) but to achieve the benefits outlined above, we want a concentrated dose of the vitamin to reach the skin directly.
The challenge in using vitamin C topically is that it must be absorbed into the skin before it can have an impact. The stratum corneum - the outermost layer of our skin that is comprised of dead skin cells and lipids - is a naturally water-resistant barrier that keeps bad things out of our bodies while holding in moisture. As Lexli founder, Dr. Ahmed Abdullah explains, "if our stratum corneum weren't water-resistant, our skin would inflate when swimming!" Because of this fact, skincare products must be formulated in a manner that can penetrate the stratum corneum or they will simply sit on the skin's surface, offering no improvement. Additionally, vitamin C becomes less potent when exposed to oxygen or exposed to light so it must be packaged in a manner that maintains its stability.
Forms of Vitamin C
Vitamin C's main form is ascorbic acid, which often appears on labels as l-ascorbic acid. This is the most popular form used in skincare products and the purest form of vitamin C. However, it is highly unstable, oxidizing quickly when exposed to light, air, or water, which can reduce its effectiveness. L-ascorbic acid also requires a low pH to penetrate the skin, which can cause skin irritation for sensitive skin types. For this reason, derivatives of vitamin C, which may be gentler while still offering excellent benefits, are often used.
Tetrahexyldecyl ascorbate (THDA) is a form of vitamin C that is quickly becoming a popular alternative to l-ascorbic acid. THDA is a lipid-soluble derivative of vitamin C that is far more stable and able to penetrate deeper into the skin due to its affinity with natural skin oils. This enhanced absorption allows it to work at the cellular level, stimulating collagen production and brightening the skin with less irritation.
Other vitamin C derivatives used in skincare products include: ascorbyl palmitate, calcium ascorbate, magnesium ascorbyl phosphate, sodium ascorbyl phosphate, and sodium ascorbate.
How to Use Vitamin C
Because vitamin C serums or creams can help to protect against sun damage, we recommend incorporating them into your morning skincare routine, immediately after cleansing your skin and before applying moisturizer. This application ensures maximum assorption and effectiveness. However, it's important to note that vitamin C will not protect your skin from sunburn. Therefore, it's still vital to apply sunscreen as your final morning skincare step.
Vitamin C serums are beneficial because of their lightweight, readily absorbed nature, which makes it easy to layer additional skincare products on top. However, vitamin C can readily be found incorporated into skincare products with other uses, such as exfoliators and moisturizers, which can make your skincare regimen even easier and more cost-effective. Regardless of the product you choose, it's wise to do a bit of research to know the form of vitamin C that is used in the product and to understand the delivery system it utilizes, while evaluating the packaging to ensure it doesn't let light in.
Finally, it's just as important to properly store your vitamin C skincare products to ensure they maintain optimal efficacy and potency. Always store them in a cool, dark location and completely close the jar or bottle after every use (better yet if the product has a pump and doesn't need to be opened!). You can expect vitamin C serum and cream to have a shelf life of 3-6 months after opening. However, we're hopeful your product won't last that long. After all, you'll only notice the benefits of vitamin C in skin if you use the product regularly.
