03 June 2021
Can you name a skincare brand that’s no frills, budget-friendly approach to well loved active ingredients? If you guessed The Ordinary, you’re right- but not really. I’m talking about a new skincare brand with a similar straightforward take on active ingredients that’s got beauty lovers excited: The Inkey List.
The Inkey List was launched last year and is now available in Singapore. The most expensive product in the Inkey List’s lineup is a very affordable $22 serum. I’m a big fan of affordable skincare and a directed ingredient based approach to skincare so I was most definitely intrigued. I bought products from the Inkey List to try and will be sharing the science of the ingredients and my reviews of the Inkey List’s products that I got. I will also be sharing how you can incorporate some of the skincare ingredients in your daily routine based on your skin type and conditions. Here’s to simpler and cost effective skincare routines!
This post will also cover new skincare ingredients such as polyglutamic acid and polyhydroxy acids; and familiar skincare heroes like vitamin C and niacinamide. So if you’d like to learn about how to use these ingredients to your benefit, read on!
To read about my review on The Ordinary’s skincare products and learn about familiar active ingredients such as vitamin C and more interesting one like copper peptides and azelaic acid, please read my post Azelaic Acid: A Multi-tasking Skincare Active to Know and The Ordinary Skincare Review and Ingredients Decoded.
The Inkey List is skincare brand from the UK that offers single ingredient product. The brand was launched last year and has often been compared to The Ordinary. The Inkey List has a straightforward and no-frills approach to its packaging is very pocket-friendly. Their products are available in Singapore through Sephora or from online retailers like ASOS.
Skincare-savvy readers would probably have heard about polyglutamic acid, a skin hydration powerhouse that’s said to hold 4 times as much moisture as hyaluronic acid.
The Inkey List’s Polyglutamic Acid serum contains 3% polyglutamic acid and 2% Invisaskin. Invisaskin is a bioadhesive copolymer that forms a seal on the skin to reduce transepidermal water loss.
What is Polyglutamic Acid?
Polyglutamic acid is a peptide from fermented soybeans, better known as natto in Japanese cuisine.
Its water loving and large molecular structure allows polyglutamic acid to attract water molecules and remain on the surface of the skin. This means that polyglutamic acid does not get absorbed in the deeper layers of the skin.
The research for polyglutamic acid is currently very preliminary and no way as robust as hydration stalwart, hyaluronic acid. Case in point: the claim that polyglutamic acid’s moisturising powers as more than hyaluronic acid was based on a small lab study. We’ll have to wait for more studies on polyglutamic acid to prove that polyglutamic acid is the game changer that it has been marketed to be.
Polyglutamic acid vs Hyaluronic acid: What are the differences?
Hyaluronic acid and polyglutamic acid may be used to moisturise the skin but they are very different.
Hyaluronic acid is naturally present in our skin as opposed to polyglutamic acid, which comes from fermented soybeans. Due to its ability to attract water molecules, hyaluronic acid is a common ingredient in moisturisers and hydrating serums. Hyaluronic acid is also the main ingredient for Profhilo and Skinboosters, two skin hydrating benefits that also reverse aging in the skin.
Although polyglutamic acid cannot be absorbed by the skin; low molecular weight hyaluronic acid can penetrate the stratum corneum of the skin.
Polyglutamic Acid is suitable for:
Normal to dry skin
Benefits of using Polyglutamic Acid:
● Moisturising effect
The good about The Inkey List’s Polyglutamic Acid Serum
The Inkey List’s Polyglutamic Acid serum feels very light on the skin and dries quickly. I use it as a moisturiser because it feels thicker than a conventional serum. When The Inkey List’s Polyglutamic Acid serum dries, it leaves a smooth finish that I like. I’m not sure whether this effect is due to the presence of Invisaskin.
The bad about The Inkey List’s Polyglutamic Acid Serum
The first thing you’d notice about using The Inkey List’s Polyglutamic Acid serum is its smell. It smells a little like petrol IMO. This smell wears off after a couple of minutes.
As much as I like The Inkey List’s Polyglutamic Acid serum, its moisturising effects were unimpressive. My skin did not feel that more moisturised or softer after using it.
My verdict on The Inkey List’s Polyglutamic Acid Serum
I really like The Inkey List’s Polyglutamic Acid serum for its finish on my skin. Even though The Inkey List’s Polyglutamic Acid is not as moisturising as it has been made out to be; this does not bother me because I do not have dry skin. If you have dry skin, you might want to layer your moisturiser on top of The Inkey List’s Polyglutamic Acid serum. If you have oily skin, you can use this as a standalone moisturiser.
The Inkey List’s Retinol Moisturiser The Inkey List’s Retinol moisturiser contains 2 types of retinoids- Retistar and granactive retinoid. This product also contains squalene.
Retistar is a stabilised form of retinol that also has vitamin E, sodium ascorbate (a vitamin C derivative) and hydrogenated castor oil in caprylic triglycerides. The Inkey List states that the concentration of retinol in this product to contain 1% stable retinol (ie. Retistar) and 0.5 granactive retinoid. See screenshot above. However, the final concentration of retinol in Retistar is 0.05% i.e. 1% Retistar concentration1% contains 0.05% retinol.
Granactive retinol is one of the newer types of retinol. It seems to bind to the same receptors as retinoic acid while causing less irritation to the skin. It seems promising. Currently, there aren’t many published clinical and independent studies on granactive retinol available.
What are retinoids?
Retinoids are vitamin A compounds. There are several types of retinoids; some of them are low potency ones that can be purchased over the counter (OTC) like retinols. There are also prescription grade retinoids like retinoic acid (tretinoin). The differences in their molecular structures between OTC retinoids and ‘stronger’, prescription grade retinoids are reasons for the differences in results. Retinoic acid can act directly on the receptors on the skin.
OTC retinoids like retinols have to undergo a series of steps to finally be converted to retinoic acid. This means that OTC retinoids are milder on the skin and take a longer period of time to see results. However, OTC retinoids are less likely to cause redness, dryness, sensitivity and irritation compared to retinoic acid/ tretinoin.
Retinoids increase cell turnover and helps with collagen production in the skin. This helps with treating acne and signs of aging. Long term use of retinoids has been associated with healthier and younger looking skin with less fine wrinkles and less hyperpigmentation. The texture of skin is also smoother and firmer.
Retinoids are suitable for:
● Oily skin
● Older skin with visible signs of aging like pigmentation, fine lines and wrinkles
● Large pores
If you are looking at preventing signs of aging, you can also start on retinoids in your twenties. Prejuvenation is a beauty trend that combines prevention of visible aging and rejuvenation of healthy skin. You read more about prejuvenation in my blog post Preventive and Baby Botox. Please note that retinoids are NOT recommended if you are pregnant. More about pregnancy safe skincare in Pregnancy Skin Care Guide: What’s Safe and What to Avoid
Benefits of using retinoids:
● Reduced acne
● Lighten pigmentation e.g. melasma
● Reduced fine lines and wrinkles
● Smaller pores
● Skin exfoliation and smoother skin
The good about The Inkey List’s Retinol serum
The Inkey List’s retinol serum actually feels more like a moisturiser so I paired it together the Inkey List’s Niacinamide serum. This pairing worked well for me. I could feel that my skin was smoother and it helped with delaying the return of blackheads after my chemical peels.
My skin was also brighter with using The Inkey List’s retinol serum. This kicked in at the 2-3 week mark for me. There is a slight stinging sensation on application but it quickly goes away.
For a non-prescription retinoid; The Inkey List’s retinol serum is very affordable.
The bad about The Inkey List’s Retinol serum
The labeling of 1% Retistar as 1% retinol. This mistake is worth highlighting because 1% Retistar only contains 0.05% retinol. The founders of The Inkey List have prided themselves as skincare experts who have extensive experience in product development, so this error is unacceptable to me. Other than this misleading label, I like the Inkey List’s retinol serum.
My verdict on The Inkey List’s Retinol serum
A decent over the counter retinol that is reasonably priced. I’d recommend for anti-aging benefits. If you have acne, The Inkey List’s retinol serum will be too mild for you.
The Inkey List’s Vitamin C serum Using topical vitamin C is a great way to amp up your skincare game against aging and pigmentation. Pure, active vitamin C (sometimes referred to as L-ascorbic acid) helps to reduce sun damage, brighten skin and increase collagen levels in the skin.
As a potent antioxidant, active vitamin C can be easily oxidised by exposure to sun and air. In my post Topical Vitamin C: One of the Best Ways to Protect Your Skin I shared about how to choose an effective vitamin C product, what to look out for in the formulation and concentration. I recommend using topical vitamin C in the day together with sunscreen. You can also read my sunscreen reviews in Sunscreen Reviews: the Best, Worst and Unsafe Sunscreens I’ve Tried.
The Inkey List’s Vitamin C serum contains 30% L-ascorbic acid stabilised in silicone.
Vitamin C/ L-Ascorbic Acid is suitable for:
Normal and older skin; pigmentation
Benefits of vitamin C/ L-Ascorbic Acid:
● Protects against sun damage including sun burns
● Brightens dull skin
● Collagen synthesis for increased firmness and reduced fine lines
● Lightens pigmentation
The good about The Inkey List’s Vitamin C serum
A whopping 30% of vitamin C in this product at an affordable price. However the catch here is that the vitamin C has been stabilised by silicones and will not be entirely absorbed by the skin. This means that effective vitamin C concentration that can be utilised by the skin in The Inkey List’s Vitamin C serum is 30%.
The Inkey List’s Vitamin C serum dries to leave a matt and poreless finish.
The bad about The Inkey List’s Vitamin C serum
If you’ve ever wondered what silicone-rich products are like on the skin, The Inkey List’s Vitamin C serum answers this question for you. It leaves a silky, satin feel but it is potentially comedogenic. It was not easy to say whether my skin was smoother or brighter with The Inkey List’s vitamin C serum because the silicone finish overwhelmed the finish. After washing off this product I did not feel that my skin was brighter or smoother after 3 weeks of use.
The Inkey List’s Vitamin C serum stung my skin for about 1-2 minutes each time I used it. The Inkey List recommends mixing its vitamin C serum with hyaluronic acid to reduce the stinging effect. Doing this would dilute the vitamin C concentration and affect its efficacy.
My verdict on The Inkey List’s Vitamin C serum
Did not work for me. The stinging effect is a big negative personally because I usually use a 20% pure vitamin C from my clinic with no issues.
Niacinamide is multitasking skincare ingredient that is suitable for most skin types. It is an antioxidant that can also be used if you have sensitive skin and acne. Some of the benefits of Niacinamide are reduced inflammation, redness and blemishes. Niacinamide also helps to increase the levels of ceramides in the skin.
I’m a big fan of niacinamide and I’ve a post on its benefits, safety and tips on how to choose Niacinamide skincare products in this post Niacinamide: A Versatile Skincare Ingredient Your Skin Will Thank You For.
The Inkey List’s Niacinamide serum contains 10% Niacinamide, 1% hyaluronic acid and 1% panthenol. Panthenol is also known as vitamin B5.
Niacinamide is suitable for:
Oily skin, acne skin, rosacea, sensitive skin
Benefits of using Niacinamide:
• Reduced sebum production
• Improvement in acne
• Improved skin barrier function
• Reduces inflammation
• Anti-aging (reduces fine lines and wrinkles)
The good about The Inkey List’s Niacinamide serum
The Inkey List’s Niacinamide serum lived up to my expectations. It reduced the oiliness of my skin and redness from retinoids. I pair The Inkey List’s Niacinamide serum with retinoids to reduce the irritation and flaking from retinoids.
The Inkey List’s Niacinamide serum dries quickly, a definite plus.
The bad about The Inkey List’s Niacinamide serum
Nothing really. The Inkey List’s Niacinamide serum worked for me.
My verdict on The Inkey List’s Niacinamide serum
A very decent niacinamide serum. The Inkey List’s Niacinamide serum lived up to my expectations (it had big shoes to fill) and is very affordable. Worth a try.
You’ve heard of alpha-hydroxy acids (AHA) and beta hydroxy acids (BHA) in my post on The Truth About Chemical Peels. Polyhydroxy acids (PHAs) are chemical exfoliants like AHA and BHA and help to exfoliate the dirt and dead skin cells on the top layer of the skin for newer, smoother and brighter skin.
The Inkey List’s PHA toner contains 3% gluconolactone, a type of polyhydroxy acid (PHA), and 3% niacinamide.
As its name suggests, polyhydroxy acids have abundant hydroxyl groups (OH).
What are Polyhydroxy Acids (PHA)?
Although Polyhydroxy acids (PHAs) were discovered a few decades ago, polyhydroxy acids (PHAs) are the latest buzzword because several famous skincare brands like Dr Jart, The Inkey List and Glossier have included polyhydroxy acids (PHAs) in their product lineup.
Before you think of polyhydroxy Acids (PHAs) as a separate chemical group from AHAs and BHAs; Polyhydroxy acids (PHAs) are actually second generation alpha-hydroxy acids (AHA). Examples of polyhydroxy acids (PHAs) include lactobionic acid, gluconolactone and galactose.
Polyhydroxy acids (PHAs) exfoliate the skin to get rid of dirt and dull skin. The molecular sizes of polyhydroxy acids (PHAs) are larger than the first generation or more traditional alpha-hydroxy acids (AHAs) like lactic acid and glycolic acid that we are more familiar with. This means that polyhydroxy acids (PHAs) is that PHAs do not reach the deeper layers of the skin like AHAs and BHAs. The implication of this is that polyhydroxy acids (PHAs) do not exfoliate as well as AHAs and BHAs at the same concentrations. Although this puts PHAs at a disadvantage; this makes PHAs causes less irritation and is more suitable for people with sensitive skin who are unable to tolerate AHAs and BHAs. Patients with conditions such as eczema and rosacea that make the skin sensitive can benefit from using polyhydroxy acids (PHAs).
Polyhydroxy acids (PHAs) are suitable for:
Sensitive skin, rosacea, eczema
If you have normal to oily skin; and if you can already tolerate AHAs and BHAs, PHAs are not going to be as effective for you.
Benefits of using Polyhydroxy acids (PHAs) :
● Chemical exfoliation: brighter and smoother skin
● Antioxidant advantage: buffer free radical damage from UV rays and environment which accelerate aging
● Some moisturising benefit
The good about The Inkey List’s PHA toner
The Inkey List’s PHA toner is very gentle on the skin. There is no stinging or skin irritation. I also like that it contains 3% niacinamide which further reduces any risk of irritation to the skin. The Inkey List’s PHA toner did make my skin feel a little smoother and cleaner after using it for about 3 weeks.
The bad about The Inkey List’s PHA toner
This was too mild for me. I was getting impatient to see results with The Inkey List’s PHA toner. To be fair to The Inkey List, I already do regular chemical peels on myself in my clinic.
My verdict on The Inkey List’s PHA toner
The Inkey List’s PHA toner is a very gentle exfoliant that’s better for people with sensitive skin. If you have acne or are already using AHAs or BHAs with no issues, you can skip this.
Botanicals and ‘natural’ skincare ingredients are trending this year as I’ve shared in my post 2020 Beauty Trends: Skincare and Beauty Treatments from Korea. One breakout skincare ingredient last year was Bakuchiol, a plant derived skincare ingredient that is said to rival the effects of retinol without skin irritation. Bakuchiol in skin care products has already been covered in my blogpost Is Bakuchiol An Effective Retinol Alternative? You can read more about the science, safety and side effects in my review.
The Inkey List’s Bakuchiol Moisturiser contains contains 1% Bakuchiol, 3% squalene and 1.5% Sacha Inchi oil. Squalene is an oil that keeps skin moisturised.
Bakuchiol is suitable for:
Most skin types, including sensitive skin. Unlikely to be useful for acne.
Benefits of using Bakuchiol:
● Anti-aging: lessen fine lines
● Lighten pigmentation
The good about The Inkey List’s Bakuchiol moisturiser
The Inkey List’s Bakuchiol moisturiser serves up a generous 1% Bakuchiol for the price tag. The addition of squalene and Sacha Inchi oil gives Bakuchiol a slight oily feel and makes it better for people with dry skin. I did not get more comedones with using The Inkey List’s Bakuchiol moisturiser.
The bad about The Inkey List’s Bakuchiol moisturiser
The Inkey List’s Bakuchiol did not do anything for me. I did not see results from using this for 3 weeks. It felt like a very bland moisturiser.
My verdict on The Inkey List’s Bakuchiol moisturiser
Possibly a non-irritating anti-aging moisturiser for sensitive and dry skin type. The Inkey List’s Bakuchiol moisturiser was lacklustre for me.
So far, I’ve reviewed the Inkey List’s skin care products in isolation to avoid any bias. I think the elephant in the room- how Inkey List compares against The Ordinary- is a question that’s on everyone’s minds.
Both The Inkey List and The Ordinary have very similar ethos- single ingredient products; simple packaging and pocket friendly prices. For similar prices, I prefer The Ordinary’s packing. The Ordinary’s serums come in dropper bottles and this allows the products to be dispensed in an easier and more controlled manner. The Inkey List’s products come in plastic bottles and tubes that feel cheaper.
The Inkey List has a couple more innovative and interesting ingredients in their skincare lineup- polyglutamic acid, PHA, probiotics and Q10. The Ordinary’s lineup focuses on more familiar tried and tested skincare ingredients.
One stand out product from The Inkey List personally is its niacinamide serum. The Ordinary’s version is my holy grail but purchasing it has been very difficult because The Ordinary is not available in Singapore. The Inkey List’s niacinamide serum is a worthy competitor to The Ordinary’s version.
Both serums contain 10% niacinamide. The Inkey List’s niacinamide serum has hyaluronic acid and panthenol. The Ordinary’s niacinamide serum contains zinc, which has mild antimicrobial benefits. I’d say The Ordinary’s niacinamide serum is more appropriate if you have acne. If you experience piling, peeling or irritation with The Ordinary’s niacinamide serum, The Inkey List’s niacinamide serum is an alternative. The Inkey List’s niacinamide serum might be better if you have dry skin due to the moisturising benefits of hyaluronic acid.
The Inkey List’s skincare products live up to expectations as a no-frills and affordable skincare line. My favourites and recommendations from The Inkey List are the niacinamide and retinol serums. The Inkey List’s vitamin C serum did not work out for me.
One plus point for The Inkey List is that it is available in Singapore through Sephora online. All in all, The Inkey List is a welcome addition to the beauty scene and a few of their products are great IMO. If you enjoyed this blogpost, you may also enjoy NIOD Skincare Review & Ingredients Decoded.
Have you tried any products from The Inkey List? What is your take on The Inkey Lists’s products?