I’ve been trying out a lot of vitamin C serums lately as long summer days and increased UV exposure looms closer. In case you’ve forgotten from my reviews of the Obagi, Indeed and Ole Henriksen serums, vitamin C is an amazing skincare multitasker. It can soak up incoming sun damage, fade existing sun damage and hyperpigmentation (such as acne scars) for a glowing complexion, and promote collagen synthesis to combat fine lines and wrinkles.
Today I’m reviewing some water-based vitamin C serums from Paula’s Choice, Ausceuticals and Ultraceuticals. The advantage of water-based vitamin C serums is that they can contain ascorbic acid, the best studied and (as far as we know) most effective version of vitamin C. Other vitamin C derivatives need to be broken down until ascorbic acid by the body before having its full antioxidant, collagen-boosting potential. (Some oil-based serums can also contain ascorbic acid in undissolved form, but its effectiveness is less certain.) On the other hand, water-based vitamin C products are less stable, so the active ingredient won’t be around as much! I’ll be reviewing some oil-based vitamin C products next.
Paula’s Choice RESIST C15 Super Booster
Paula’s Choice RESIST C15 Super Booster contains 15% vitamin C in the form of ascorbic acid, along with vitamin E (tocopherol) and ferulic acid. This antioxidant triple combo is commonly known as C+E+Ferulic. Antioxidant ingredients can work synergistically to replenish each other, which means greater overall antioxidant ability (read: anti-aging action). This means it works better on the skin – vitamins C and E together are twice as effective at UV protection as either vitamin alone, while C+E+Ferulic was found to be twice as good as vitamins C + E together or ferulic acid alone.
It also oxidises slower in the bottle, so the shelf life is much better. A water-based ascorbic acid serum by itself has a shelf life of a few weeks before it’s too oxidised to be beneficial, which you can see as the serum turns yellow in colour. In contrast, the C+E+Ferulic combo has a shelf life of a few months (longer if you keep it in the dark, without air exposure and in a cold place).
RESIST C15 Super Booster ($62 AUD or $49 USD for 20 mL) is formulated at a pH of around 3 for efficient penetration of ascorbic acid, which is well known for being a difficult ingredient to get to absorb into the skin. It comes in an opaque orange dropper bottle, which unfortunately allows for a lot of air exposure.
The biggest disadvantage to this product though, in my opinion, is the smell, which can best be described as “hot dog water”. I’m sure a lot of people will be able to handle it, which mostly goes away once you put moisturiser on it, but I found it difficult to convince myself to use it regularly. It’s my main gripe with fragrance-free products – if a pleasant fragrance makes me want to repeatedly use the product, then it’ll be more effective than a fragrance-free product. I’ve passed this onto my sister who can barely smell it, so it’s not a dealbreaker for everyone.
Water, Ascorbic Acid, Ethoxydiglycol, PPG-26 Buteth-26, PEG-40 Hydrogenated Castor Oil, Tocopherol, Ferulic Acid, Sodium Hyaluronate, Acetyl Octapeptide-3, Glycerin, Panthenol, Sodium Metabisulfite, Triethanolamine, Phenoxyethanol.
Ausceuticals 20% C+ Serum
Ausceuticals is a small skincare company based in Perth, Australia that I’ve recently discovered. Their products are quite science-based, and are formulated with the aim of keeping them as inexpensive as possible.
The 20%C+ Serum contains the C + E + ferulic acid combo, as well as a laundry list of other antioxidants too: phloretin, astaxanthin, lycopene, lutein, alpha lipoic acid, beta carotene, fucoxanthin, cranberry juice and pomegranate seed oil. The rest of the ingredients are mostly humectants (sea kelp bioferment, glycerin, sodium PCA, hydrolyzed collagen, hyaluronic acid). It has a light citrussy scent and comes in an opaque pump bottle (though unfortunately not airless). The pH is 2.7, which is in the correct range for ascorbic acid to be effective. The best thing about this serum is that it’s only $39 AUD for 30 mL, which is very budget-friendly for a product with so many effective ingredients! This is my pick of the three serums here.
Water, Sea Kelp (Lactobacillus/kelp ferment filtrate) Bioferment, Glycerin, Ascorbic Acid (L), Sodium PCA, Cranberry (Vaccinium macrocarpon) Juice, Ferulic Acid, Phloretin, Hydrolyzed Collagen, Hyaluronic Acid, Porphyridium Extract, Fucoxanthin, Cranberry (Vaccinium macrocarpon) Extract, Pomegranate Seed (Punica granatum) Oil, Tocotrienols, Vitamin E Oil (Alpha-D Tocopherol), Astaxanthin, Lycopene, Lutein, Alpha Lipoic Acid, Beta Carotene, Fragrance, Phenoxyethanol (and) Caprylyl Glycol (and) Sorbic Acid
Ultraceuticals Ultra C10+ Firming Serum
Ultraceuticals Ultra C10+ Firming Serum contains 10% ascorbic acid with a bunch of anti-aging peptides (palmitoyl hexapeptide-12 (pal-KTTKS), palmitoyl tetrapeptide-7, palmitoyl tripeptide-1, oligopeptide-1). The scent is mostly alcohol, with a very slight metallic tinge. It’s quite pricey ($110 AUD for 30 mL), and while Ultraceuticals seems to have worked out a way of stabilising the vitamin C, it’s hard to tell how oxidised the product is since it comes yellow. If you’re looking for a vitamin C serum in combination with anti-aging peptides, I’d recommend paying a little bit extra ($138 AUD for 30 mL) for the 23% version (C23+ Firming Concentrate), which is water-free according to the ingredients list, so it’s easier to tell if it’s gone off.
Aqua, Alcohol Denatured, Ascorbic Acid, Ethoxydiglycol, Glyceryl Polymethacrylate, Glycerin, Propanediol, PEG-8, Palmitoyl Hexapeptide-12, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1, Caproic acid, Oligopeptide-1, Sodium PCA, Polysorbate 20, Dextran, Hydroxyethylcellulose, Carbomer, Anogeissus leiocarpus Bark Extract, Menyanthes Trifoliata Leaf Extract, Butylene Glycol, Caprylyl Glycol, Caprylhydroxamic Acid, Disodium EDTA, Lactic Acid, Sodium Hydroxide.
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