Vitamin C in Skincare Vol 1.

One of the most popular functional actives in skincare, Vitamin C deserves a place in pretty much every skincare routine. But it is shrouded in misinformation and there are key ‘insider-info’ tips which will make the difference between bleh results and seeing your skin transform. Let’s take a deep dive into this superhero ingredient known for its protective, glow-boosting and pigmentation-busting properties.

Why do you want to use it?

  • It is a powerful antioxidant, preventing or reducing damage to our cells by neutralizing the production of highly reactive molecules called free radicals which bombard our skin daily (think pollution, UV, blue light etc)
  • It boosts how effectively our sunscreen is protecting our skin from UV damage (in ‘derm’ terms, we call this being photo-protective)
  • It is pro-collagen: it is a cofactor for at least 8 enzymes essential for collagen production, is critical in building strong, cross-linked collagen and it prevents collagen breakdown
  • It lightens pigmentation both by interacting with copper ions necessary for a key enzyme in the pigmentation pathway (tyrosinase) as well as by preventing reactive oxygen species from triggering pigmentation 
  • Certain Vitamin C derivatives are anti-acne (eg sodium ascorbyl phosphate)
  • It hydrates the skin by replenishing the lipids that are naturally present in the skin barrier
  • It helps wounds heal (through its collagen-boosting efforts) while also reducing inflammation and the risk of post-inflammatory pigmentation  
  • It boosts the skin cell turnover time resulting in healthier, more youthful skin

In simple terms: you can expect an improvement in fine lines and wrinkles/ skin texture/ pigmentation and get the peace of mind that it is making your sunscreen work even better and giving you top-notch defense against pollution and other environmental insults.

Isn’t it enough to get your Vitamin C through your diet ?

Vitamin C is a vitamin which we as humans cannot make and even if you supplement with large quantities of oral Vitamin C, very little actually becomes biologically active in the skin. This means that you cannot sip your orange juice and think that you don’t need to splurge on that Vitamin C serum. Unfortunately, applying Vitamin C topically to the skin is the best way to harness its superpowers. 

When can you expect to see results?

Antioxidant superpowers: immediately
Skin-brightening: 6-12 weeks
Pro-collagen effects/ reduction in fine lines and wrinkles: 3-6 months (very dependent on the type of Vit C)

What should you be looking for in the ingredients list?

This is what makes Vitamin C so confusing – there are SO many forms. You are looking for: L-ascorbic acid, Tetrahexyldecyl ascorbate (THD), Ascorbyl Tetraisopalmitate, Magnesium ascorbyl phosphate, Sodium ascorbyl phosphate, 3-O-ethyl ascorbic acid, Ascorbyl glucoside, 3-O-ethyl ascorbic acid, ascorbyl palmitate.

NOTE: ingredients such as Kakadu plums for example, hyped for their high Vitamin C concentration is NOT the same thing as applying L-ascorbic acid. If you’re applying other Vitamin C-rich ingredients, don’t be disappointed when you do not see the same results as ‘authentic’ Vitamin C.

Which form is the best?

Wrapping your head around the various (overwhelming) types of Vitamin C can be simplified through understanding one basic principle:L-ascorbic acid (L-AA) is a complete diva to formulate with. Its potency as an antioxidant in its ability to donate electrons to unstable free radicals also makes it extremely volatile to compound with. It oxidises, it’s unstable and it’s irritating to the skin at scientifically proven concentrations making it poorly tolerated. Formulators persevere with it because it is the active form of Vitamin C backed by the most scientific evidence and does not require conversion in the skin but can act directly to affect its magic.

Enter esterified or inactive forms of Vitamin C derivatives which get activated and converted to L-ascorbic acid when applied to the skin (read: all other forms of Vitamin C). These are more stable, less irritating and in some cases where they are lipid-soluble, penetrate the skin better.


 Vit C derivatives are synthesized by blocking the reactive site of the L-AA molecule with a hydrocarbon chain that increase both the stability as well as bioavailability. These side chains are broken off by the enzymes in the skin to transform it into ascorbic acid. These molecules are stable at physiological pH (5-7) and are suitable for sensitive skin types.

So although many skincare purists still rate L-ascorbic acid as the top choice – particularly when it has been stabilized and potentiated by combining it with other antioxidants such as Vitamin E and Ferulic acid – the ‘best’ choice really comes down to you, how sensitive your skin is and what you are trying to treat.

If you have sensitive, reactive skin then the low pH of L-ascorbic acid is a recipe for skin irritation – rather look for products containing the Vitamin C derivatives as these are typically less acidic forms of vitamin C and so better suited to sensitive skin. For even gentler delivery, you might also like to consider choosing a Vitamin C moisturizer rather than a serum – just make sure it is in an airless pump.

The derivatives that have the most data for collagen production and hyperpigmentation are the lipid-soluble Vitamin C derivatives Tetrahexyldecyl ascorbate and ascorbyl Tetraisopalmitate. Personally Tetrahexyldecyl ascorbate remains my top Vitamin C pick since it is stable and the fact that it is lipid-soluble means that it penetrates into the dermis where it gets converted to L-ascorbic acid and does everything that L-ascorbic acid does without the irritation.

Not all Vitamin C’s are born equal!

Stay tuned for another TASH360 Vitamin C edition where we will dive deeper into Vitamin C’s with my top picks!

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"Anything’s possible in life when you look and feel your best. We can help you achieve clear, healthy skin – the rest is up to you."

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