How to: Debunk common myths about Vitamin C with your clients

Vitamin C is one of the most beneficial actives a client can include in their routine. Particularly in Australia where our UVA/UVB index is one of the highest in the world, Vitamin C provides superior antioxidant protection and anti-ageing benefits.

But, there is plenty of misinformation circulating about this hero ingredient online. From beliefs that Vitamin C can “stain” the skin, to confusion around what other actives it can be combined with, and the conviction that all Vitamin C’s are created equal (no, the $10.00 Vit C your client picked up on Amazon is not as beneficial as the cosmeceutical strength Vit C you range). We spoke to Doctor Cara McDonald about common Vitamin C myths she encounters in clinic, how she explains them to clients and her Vitamin C of choice.

How would you describe the benefits of Vitamin C to a prospective customer?

Vitamin C is an antioxidant that provides protection against free radical damage, ageing, and can quell inflammation while brightening the complexion for more radiant skin.

Firstly, oxidation is a process within the body that contributes to a build-up of toxins and damages cells and proteins such as collagen. Antioxidants act to neutralise free radicals and reduce oxidative damage. They are obtained through our diet, but can also be delivered directly to the skin via topical application, which has been proven to decrease cellular damage and premature ageing.

Vitamin C serums can range from $20.00-$400! How do you describe the differences in formulations, when they may even contain the same “hero” ingredients?

The difference all comes down to the parameters the Vitamin C is formulated in. The effectiveness of active ingredients in the skin is determined by the quality and concentration of the active, as well as the delivery mechanism and ability to reach the target in a bioactive form. Vitamin C is a highly potent antioxidant, but by the nature of its structure, it can be unstable and has difficulty being absorbed into the skin.

Ranges like SkinCeuticals are formulated within the Duke Antioxidant parameters. These are the criteria for effective delivery of Vitamin C to target the skin – therefore, they are guaranteed to deliver the results we expect from the highest quality products.

Dr. Cara Mcdonald
Dr Cara McDonald preferences SkinCeuticals products when selecting antioxidants for her clients, as they’re formulated within the Duke Parameters – maximising ingredient penetration and efficacy.

Many consumers believe that Vitamin C, like some other active ingredients, will make their skin more sensitive to sunlight. Is this true?

What’s interesting about Vitamin C is it’s not like other acids and does not increase sun sensitivity; instead, when used during the day it helps protect the skin against free radical damage from UV rays. Combined with SPF, it’s the perfect combination to defend your skin against these environmental aggressors.

There are also complimentary ingredients that further boost these effects. For example the antioxidant serums from SkinCeuticals (CE Ferulic, Silymarin CF and Phloretin CF) are all formulated with ferulic acid, which enhances the effects of other antioxidants such as Vitamin C, to neutralise free radicals and provide preventative protections against visible signs of ageing such as fine lines, wrinkles and dark spots. Vitamin C is best used during the daytime as your skin is exposed to more external aggressors during the day.

With the rise of brands like The Ordinary, that advertise percentages on every bottle, skincare lovers have become very preoccupied with the amount of an ingredient in a product. Are actives a percentage game and is more always better?

A formula that contains a high percentage of Vitamin C, but isn’t optimally formulated will be far less impressive than a Vitamin C formula wit ha smaller concentration. It really depends on he delivery of the active ingredient to the target in the skin. Additionally, a higher concentration can result in skin irritation and limit the tolerability of the product. I would say to clients that while you may get caught ub in the numbers, it’s best to focus on the formulation and how well it absorbs into the skin, I recommend looking for products with scientific studies that back their claims.

Antioxidants in SkinCeuticals are truly the gold standard when it comes to formulation and percentages, as they’re formulated within the Duke Antioxidant patent. This outlined the formulation parameters required for the effective delivery of Vitamin C to the skin: 1) pure l-ascorbic acid (Vitamin C); 2) an acidic pH within the 2.0-3.5 pH range and; 3) a concentration between 10-20%.

Do antioxidants have to come from fruits and berries?

No at all! Antioxidants can be found in almost every aspect of the plant kingdom. The most recent Vitamin C serum from SkinCeuticals – Silymarin CF – is derived from the milk thistle plant.

Many clients are using multiple actives in their skincare routines – and there is online conjecture about which actives can be combined. What is your advice to clients incorporating Vitamin C with other actives?

It is true that we need to be careful with overdoing it with too many active ingredients, but, Vitamin C can certainly be used in conjunction with other acids and retinols. The key is to introduce active products one at a time and let your skin adjust before starting another one. If you have very sensitive skin or have sensitized it through excessive product use, then it is best to seek professional advice around how to repair your skin and build up tolerance to the active ingredients you’d like to use.

In general, Vitamin C is completely safe to use in conjunction with niacinamide, and combining these two can actually do wonders for your skin if you have pigmentation and discolouration.

With retinols and AHA’s, it’s best to space these out throughout your routine – e.g. Vitamin C during the day and retinol/ahas at night. Also, it’s all dependent on your skin and what works. When combining a lot of actives, it can lead to irritation on the skin, so go slowly and choose th right products for your skin type.

Lastly, there have been some reports of Vitamin C discolouring or “staining” the skin – is this possible?

If your Vitamin C is giving you discolouration, that means the product has oxidised and degraded, so it is no longer active and won’t have any effect on your skin.

Want more ingredient-focused explainers? We interviewed Dermatologist Michelle Rodrigues on the benefits (and risks) of Hyroquinone.

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