A tell-tale sign of vitamin c over-use can be increased blackheads or a development of blackheads. General skin irritation and breakouts can also occur if you are using your vitamin c too much or too often. We recommend using your serum 1-2 times a day and 2-4 drops is all that is needed.
According to studies, the benefits of Vitamin C serums tend to continue increasing along with increased strengths, but only up to about 20% concentrations. After 20% Vitamin C content, you may run into more irritation from the high concentrations without seeing much benefit in return.
Vitamin C serum benefits
If you're wondering when to apply a vitamin C serum, the answer is both morning and night, after cleansing and toning. One study even recommends applying a vitamin C serum every eight hours, or twice daily for the pinnacle of protection.
If you use too much vitamin C on your skin, it may cause flakiness, so start with a small amount as you get used to the product. Finally, always wear sunscreen when using vitamin C in your skincare routine. Without an SPF50, the vitamin can actually cause more sun damage.
Most of the skincare experts we spoke with recommend adding a Vitamin C serum to your skincare routine slowly before building up a daily or twice-daily tolerance. “I recommend every other day to daily use in the morning, typically three to five drops for the entire face,” Palm says.
Vitamin C can be very acidic, and serums can cause skin irritation in some people, particularly in high concentrations. When using a vitamin C serum for the first time, apply a thin layer every other day and gradually increase to daily applications.
If you are applying a Vitamin C serum and hyaluronic acid separately, it's suggested that you apply the Vitamin C first, and then add the hyaluronic acid afterward in order to help fortify the skin barrier and lock in the moisture.
Can You Use Hyaluronic Acid and Vitamin C Together? Not all powerful skincare ingredients can be mixed, but hyaluronic acid and vitamin C are two that become even stronger when paired with one another. These ingredients can provide both immediate and lasting results when used together in anti-aging formulations.
7 vitamin C serums to consider
Sometimes it can be too strong for your skin, causing it to react via purging, breakouts, or itchiness. You don't want the product to sting and itch even after you apply moisturizer.
AHAs and BHAs, such as glycolic, salicylic, and lactic acids should never be used with Vitamin C. Vitamin C is an acid, too, and is unstable, so the pH balance will be thrown off by layering these ingredients together and might as well be useless.
Pat any excess product onto the top of your hands, neck, and décolletage. Step 4: Apply a moisturizer (Yes, your moisturizer should come after your Vitamin C serum — remember the “thinnest to thickest” rule.)
For those with sensitive, reactive skin, certain forms of vitamin C can be shockingly irritating, leading to dryness, peeling, and redness.
Best overall vitamin-C serum
Four of our dermatologists recommend SkinCeuticals C E Ferulic, which they (and our editors) hail as the gold-standard vitamin-C serum and is suitable for all skin types.
When vitamin C acts as a pro-oxidant, the consequences include irritation, inflammation, collagen and elastin breakdown, and acne. So if you have any of these skin ailments, and are using a vitamin C serum, then its time to re-think your regimen.
While this often occurs in old formulas within a bottle, vitamin C can also oxidize on your skin when it comes into contact with oxygen. This creates hydronium ions, according to Veronique, which can lead to skin sensitivity.
When should you throw out a vitamin C serum? Once your serum begins to turn yellow, it is a clear sign that too much air has mixed with the formula making the vitamin C less potent, once the formula becomes discoloured in any way it is best to throw out the product completely.
Sudden acne breakouts can be because of numerous reasons, including hormonal changes or hormonal imbalance, an unhealthy diet including lots of deep fried and junk food, release of cortisol hormones because of excessive stress, excessive production of sebum and much more.
So if you used a vitamin C serum and it gave you acne, redness or any other skin issue, it is because the serum took away your body's ability to fight off bacteria, and weakened it, inviting pathogens to infect your skin.
Anything that makes your skin cells turn over faster can cause skin purging, so generally those with exfoliating benefits, such as retinoids (Vitamin A), Vitamin C (a very gentle acid that can slough off dead superficial skin) and hydroxy acids (glycolic acid, malic acid and salicylic acid).
So, should I use vitamin C or retinol for wrinkles? Well, when it comes right down to it, the choice is really in what you're looking to do for your skin. While vitamin C is incredible for the skin because of its ability to help brighten and improve hyperpigmentation, the best active ingredient for wrinkles is retinol.
"Because vitamin C serum helps protect your skin from free radicals, most dermatologists have recommended applying it in the morning to prevent damage during the day," says Joshua Zeichner, the director of cosmetic and clinical research at Mount Sinai Hospital in New York City.
The truth: You can use vitamin C with retinol and retinoids. Get them as separate products so you can tailor the concentration of each and use them at the right time of day. Although vitamin C can be used day or night, it is ideal for daytime use, while retinol and retinoids should be applied at night.
Don't Mix: Retinol with vitamin C, benzoyl peroxide, and AHA/BHA acids. AHA and BHA acids are exfoliating, which can dry out skin and cause further irritation if your skincare routine already includes retinol. As for benzoyl peroxide and retinol, they cancel each other out.
Is it a good idea to combine Vitamin C, Retinol and Hyaluronic Acid in a skincare routine? Yes. These ingredients work well when used individually and even better when paired together.