Vitamin C is a powerful and essential antioxidant. It serves many functions in our bodies and plays a crucial role in the health and beauty of our skin. It helps build and strengthen tissues in the body such as collagen and the walls of blood vessels. Our bodies aren’t capable of producing Vitamin C, which means we must consume it, and it’s a water-soluble vitamin, so it doesn’t get stored in the body. It must be replenished frequently. For maximum anti-aging, we should be both consuming sources of Vitamin C and apply it topically.
Key Benefits of Vitamin C:
- protects us from free radicals (antioxidant)
- synthesizes collagen
- reduces unwanted pigmentation
Free Radical Protection
UV rays and environmental factors like pollution, smoke, and smog cause the release of damaging free radicals. Free radicals are unstable molecules that steal electrons from healthy molecules to reach equilibrium. When these molecules go unchecked, they can cause real skin damage and lead to premature wrinkling, age spots, or even cancer. Vitamin C protects the skin from this type of harm like almost no other antioxidant can.
Since sunscreen is far from a perfect science (read more here), using a Vitamin C serum is a great way to sort of “backup” your sun protection. Of course, the only surefire way to avoid sun damage is to stay out of the sun entirely, but that isn’t practical 100% of the time. So, you can layer a Vitamin C product underneath your sunscreen to increase photoprotection. You can also apply a Vitamin C serum after sun exposure. Vitamin C levels in the skin are depleted after sun exposure, and studies show that skin is less damaged when Vitamin C is applied both before and after UV exposure.
Vitamin C should never be used in lieu of a good broad-spectrum sunscreen, of course. It isn’t a barrier to UV rays. Think of it as giving a “boost” to your sunscreen. It slows the rate of free radical damage by the UV rays that sneak past your sunscreen.
Vitamin C is required for collagen synthesis. Increasing dietary intake as well as applying an effective topical will boost collagen levels. L-ascorbic acid is the bioavailable form of Vitamin C needed by skin cells to produce collagen. You’ll sometimes see it listed as simply “ascorbic acid.” (All ascorbic acid in skincare is “L-ascorbic acid,” but sometimes manufacturers leave the “L” off.) Vitamin C also increases the synthesis of ceramides. This improves the condition of dry skin and the overall function of the skin’s barrier.
Reduces Unwanted Pigmentation
Topical use of Vitamin C has been shown to interfere with melanin formation. Melanin is the pigment that gives your hair and skin it’s coloring. When there is too much melanin in an area, it shows up as a darker spot, and we call it “hyperpigmentation.” Vitamin C can give skin a lighter and brighter appearance by inhibiting hyperpigmentation.
The key is not to allow UV exposure to re-darken areas of hyperpigmentation. Many people get frustrated after using “lightening/brightening” products with little success but are failing to protect their skin from the sun, rendering their lightening efforts futile. Often areas of excess melanin got there in the first place with the help of UV exposure. Allow about 4-6 weeks to see the brightening effects from consistent use of a quality Vitamin C serum. Vitamin C serums are very tricky to formulate though, and as such, they are not all created equal.
The Different Forms of Vitamin C: Ascorbic Acid
Remember I said that ascorbic acid is the bioavailable form of Vitamin C necessary for collagen synthesis? It’s the most potent, pure form you will find in skincare. Unfortunately, there is one giant caveat when it comes to ascorbic acid: it is particularly unstable.
Ascorbic acid is a water-soluble, fine, white powder. Once mixed with water it has a very short shelf life. In water, it starts out yellow, turns orange, and once oxidized entirely becomes brown. Once oxidized, it is not only ineffective but is harmful to use, as it will generate free radicals in your skin. Sunlight, heat, air, and time can also render ascorbic acid ineffective.
Proper product formulation will stabilize ascorbic acid, and skincare companies spend a lot of time and money working on just that; it’s part of the reason some Vitamin C serums can cost so much money. The good news is you can find stable ascorbic acid-based products at any price point.
The tricky thing about looking at products with ascorbic acid is that the ingredient list (usually) won’t tell you whether or not it contains stabilized ascorbic acid. Unless it explicitly states somewhere on the packaging or in the marketing that the ascorbic acid is “stabilized,” I won’t purchase the product (especially if it is a water-based serum). Also, ascorbic acid products should come in darkly colored or opaque containers since light will cause them to oxidize more rapidly. Here are several suggestions for ascorbic acid-based skincare that are stabilized (or don’t require it):
Sometimes products will have ascorbic acid paired with another antioxidant called ferulic acid. Ferulic acid has been shown to help stabilize ascorbic acid in water, and it gives added protection from the sun as well.
Keep your Vitamin C serum in a dark, cool, dry place. Even products that have been formulated correctly will oxidize eventually.
Something else about ascorbic acid: it’s the acidic form of Vitamin C, so it can sometimes cause a bit of irritation. Also, for ascorbic acid to absorb through your stratum corneum effectively, the pH of the product itself must be low (or acidic). It can take time for your skin to become accustomed to it. At first, it might be wise to apply your product sparingly or every other day until you know how your skin will respond. You may feel an intense tingling sensation upon application of certain ascorbic acid products.
More types of Vitamin C: (THDA), (SAP), and (MAP)
Ascorbic acid isn’t for everyone. Due to the potential for irritation and the complexities of stabilization, skincare manufacturers will often choose from some more stable vitamin C derivatives. Here are some other names Vitamin C goes by in skincare:
- Sodium Ascorbyl Phosphate (SAP)
- Magnesium Ascorbyl Phosphate (MAP)
- Tetrahexyldecyl Ascorbate (THDA) or Ascorbyl Tetraisopalmitate
- Ascorbyl Glucoside
- Ascorbyl Palmitate
- Sodium Ascorbate
- Ascorbyl Glucosamine
- Ascorbyl Methylsilanol Pectinate
- Ascorbyl 2-Phosphate 6-Palmitate (APPS)
- 3-O-Ethyl Ascorbate (EAC)
The first three on the list are what to look for if you are concerned with anti-aging. Tetrahexyldecyl ascorbate (THDA) is the best alternative to ascorbic acid. It penetrates easier and into deeper layers of the skin than pure ascorbic acid can. Preliminary studies are confirming that it converts to ascorbic acid in the skin. As more studies are done on THDA, you may see more of it popping up, as it has many advantages over ascorbic acid.
Here are a few recommendations for serums containing THDA:
You’ll find an abundance of Vitamin C infused moisturizers and serums that use sodium ascorbyl phosphate (SAP) and magnesium ascorbyl phosphate (MAP) as (one of ) their active ingredient(s). SAP and MAP excel the most at antioxidant protection and brightening.
Any of the Vitamin C derivatives work well as anti-oxidants, but if you’re looking for collagen synthesis, ceramides, and skin brightening, you want the most potent form of C your skin can tolerate. (Remember, the higher up it appears on the list of ingredients, the higher percentage of that ingredient you’re getting in the formula.)
And don’t underestimate the importance of getting enough Vitamin C in your diet. Studies have shown that a higher intake of Vitamin C (and lower intake of carbohydrates and fats) leads to less wrinkling, dryness, and atrophy of the skin over time. Provide your body with what it needs to make collagen and fend off free radicals by eating right and using the right skincare.
Sunscreen, Vitamin C, and Retinoids
If you have limited money to spend on skincare, spend it on these three things. You don’t have to pay a ton for fancy cleansers, toners, and moisturizers. Sunscreen, Vitamin C, and Retinoids are essential for basic but effective anti-aging skincare. That’s not to say there aren’t other exciting actives out there for anti-aging. But you will have beautiful skin by merely sticking with these three.
Use a Vitamin C product and sunscreen in the morning and a Vitamin C product and a retinoid in the evening. Then use a gentle cleanser and a moisturizer appropriate for your skin type. Both Vitamin C and retinoids can irritate, so you don’t want to upset the skin by throwing too much at it at once.
Be sure to read about using retinoids correctly here. You may not be able to use them every night.
Remember, you can buy the most potent Vitamin C serum out there, but if you seldom use it because it doesn’t agree with your skin, then it’s doing you no favors. Better to use something gentle every day than something irritating once in a blue moon. Consistency is key with skin care.
Barnet Products Corp, Stable forms of Vitamin C, Technical Bulletin, 2001
https://incidecoder.com/ (fantastic blog)