Which Vitamin C is Best For You?

Posted by Azadeh Shirazi MD on

Which Vitamin C is Best For You?

Vitamin C is one of the most popular ingredients in skincare. In fact, it’s so popular, that it’s been on the top 5 trending ingredients list for the last three years! You probably already have it incorporated into your skincare routine but if you’re still wondering why this staple has become the holy grail, how to use it, and ways to avoid any adverse reactions, keep reading.

I also have a detailed Youtube video dedicated to this topic, check it out below! 

 What is Vitamin C In Skincare?

Vitamin C, also known as L-ascorbic acid, is an antioxidant that offers lightening, brightening, and tightening effects on the skin. Our skin needs vitamin C to make collagen; landing it a staple in anti-aging routines. It is unanimously known for promoting glowing skin but it also offers many other benefits, such as:

  • Protecting against free radical damage
  • Enhances SPF’s UV Protection
  • Fades Discoloration and Acne Scars
  • Reduces the signs of aging by stimulating collagen production. 

Who Should Use A Vitamin C?

If you’re looking to promote a healthy glow and add vibrancy to you skincare routine, vitamin C is the perfect ingredient to add. It is also a great preventative product and typically works well for those with combination, oily, or dry skin. Based on the benefits previously listed, Vitamin C can benefit those most affected by

  • Acne Scarring
  • Melasma
  • Sun spots; Dark Spots
  • Aging; Fine Lines and Wrinkles; Dullness 
  • Decreased Collagen Production
Who Should NOT Use A Vitamin C?

Those using retinoids should use caution with vitamin C as it can be irritating to the skin. Sensitive skin types might also find Ascorbic Acid irritating and should test a small area before applying.

There are new analogs of Vitamin C on the market called Tetrahexyldecyl Ascorbate, a very stable form of vitamin C. As an ingredient that is notorious for being unstable and irritating at high concentrations, THD is a new alternative for those who cannot tolerate Ascorbic Acid.

When Should I Use Vitamin C?

Vitamin C is best applied in the morning after you cleanse. It will help fight against free radical damage you might encounter throughout the day, while also brightening your complexion. My skincare philosophy is easy: cleanse, treat, protect. Because L-Ascorbic acid usually comes in a serum form it is applied during the treatment portion of your skincare routine, followed by an SPF. It can be applied at night if you’re not using other actives.

When Should I NOT Use Vitamin C?

Although Vitamin C offers many benefits, it may not be suitable all the time or for every skin-type. Avoiding using in combination with these actives:

  • Benzoyl Peroxide 
  • Retinols 
  • Additional Acids (Glycolic, Salicylic, Citric, etc.)
  •  Combining Vitamin C with other actives can irritate the skin, ultimately causing redness and dryness; especially if you already have sensitive skin. It’s best to keep your skincare routine simple. If you’re using a retinol or any type of exfoliant, use it in the evenings and your Vitamin C in the mornings. 

    Dr.Azi’s Recommended Products: 

    • IllumiC with Ferulic Acid: 15% pure L-Ascorbic Acid in a hydrating serum that rejuvenates the skin. Contains Ferrulic acid and Vitamin E to firm, hydrate, brighten the skin.
    • Glow Serum: Best for those who cannot tolerate ascorbic acid. This 20% Vitamin C is a combination of Ascorbic Acid and Tetrahexyldecyl Ascorbate, designed to brighten dullness, lighten hyperpigmentations, and support collagen production to improve the appearance of lines and wrinkles. 

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    • Is there a vitamin c you can recommend that I can purchase over the counter?

      Lizi D on

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    Dr. Azadeh Shirazi, MD is a Board-Certified Dermatologist.

    Specializing in medical, surgical, and cosmetic dermatology, Dr. Shirazi received her undergraduate and medical degrees from the University Of Kentucky College of Medicine. After doing a Research Fellowship at Harvard Medical School at the Wellman Center for Photomedicine, she completed her residency training in Dermatology and Cutaneous Surgery at the prestigious Mayo Clinic in addition to completing her training in dermatology and cosmetic surgery at the University of California San Diego.

    She has received multiple research scholarships from iconic institutions including Harvard University and the University Of Texas Southwestern Medical Center and has several peer-reviewed publications to her name.