The ESK blog

Why We Choose Retinal and What Makes Evidence (Based) Skincare Different

20 July 2021

Dana Raffoul

Updated 14/07/2026

Without question, when it comes to anti-aging skincare, the best studied and most effective ingredient with the strongest evidence is Retinoic Acid (prescription Vitamin A a.k.a. Tretinoin). But it can be very irritating and drying and it is a prescription only ingredient. So the question is, what is the ingredient that gets the results of Retinoic Acid, without the irritation?

Spoiler alert, when we found that the answer was an ingredient that is incredibly rarely used in skincare – that was one of the main reasons we started Evidence Skincare (ESK).

Before we dive in, it’s important to note that well before the first trial of prescription Vitamin A was conducted in the 1940’s, it was highly effective we just didn’t know it then. Sure there would have been a few people who suspected it was, and they had even done some of their own experiments. It wasn’t until many properly designed and executed trials had been conducted, and the conclusions of those trials had been subjected to peer review and approval before being published that we had enough evidence to be confident that it worked really well. In fact, if you have some spare time, enter https://www.ncbi.nlm.nih.gov/ into your browser, then type “topical tretinoin” in the search bar – if you are ready for a geek party, head over to the first of 1,597 journal articles which discuss prescription Vitamin A 😊

Compare that to one of the newer forms of Vitamin A which is marketed as one “ that offers a multi-fold better effect against signs of aging than retinol, retinyl palmitate and nearly all other forms of non-prescription retinoid”. Now that is a great claim! But how do we know whether we can be confident that it is accurate? Well if you type the name of the ingredient (Hydroxypinacolone Retinoate) into the search bar in https://www.ncbi.nlm.nih.gov/ the result is a little less intimidating. There are just 4 journal articles which appear. And there is only one laboratory (not human) study, sponsored by the manufacturer which actually studies the ingredient. While the study is interesting, it is biased and tells us nothing about whether the ingredient actually works when used by real people… so we can’t have any confidence that the ingredient even works, never mind living up to its lofty marketing claims. And it will stay that way unless some evidence actually starts to emerge from properly conducted trials whose results are subjected to (independent) peer review prior to being written up in respected scientific journals. We don’t have to look too far to see how premature conclusions can be wrong when properly tested… does anyone remember Hydroxychloroquine?

So back to Retinal and how we chose it. The first thing we did was scour journal articles and the market for all of the promising active ingredients that were available and used. There were over 30 of them that made our original list. We then looked at the journal articles describing these ingredients and the underlying studies,based on that we selected only the ingredients with the best available evidence. And the ingredient that ended up having the best evidence is Retinal. Happily we aren’t the only ones who have combed the evidence, in fact there are peer review journal articles doing just that. And when (just some of) these journal articles say

It makes us confident that when we say Retinal is the best evidence-based ingredient to include in ESK, we’re in good company.

SHOP ULTIMATE A GOLD

A Vitamin A (Retinal – 0.1%), 4NB (4-N-Butylresorcinol – 0.1%) and B3 (Niacinamide – 5%) based night cream. For repair and rejuvenating normal, drier, pigmented and aged skin. *Suspend use of Vitamin A products if pregnant of breastfeeding.

Ultimate A Gold

Ultimate A Gold: the most effective and gentle ingredients that evidence based cosmeceutical skincare has to offer, in one revolutionary formula.

The game-changing night cream developed in partnership with Selma Blair - combines our most potent hero ingredients to effectively and gently tackle the most common skin concerns – in one product.

Tackling the signs of aging skin including fine lines, skin elasticity, impaired barrier function, hydration, dullness and uneven skin tone. it is our most powerful product yet and yet it’s still ridiculously well tolerated.

Wake up to skin that's supple, smoother, and softer.

For the most irritable of skin, Ultimate A may be a better option, particularly when starting to use Retinal based products

*Ultimate A Gold (Retinal) may transfer onto white or light-coloured fabrics. For best results, we recommend using darker clothing or surfaces to avoid visible marks.

SHOP ULTIMATE A+

A Vitamin A (Retinal – 0.1%), B3 (Niacinamide – 4%) and AHA (Glycolic Acid – 2%) based night cream. For repair and rejuvenating normal, oilier and thicker skin types and for management of mild to moderate acne.

Ultimate A+

Building on the proven performance of Ultimate A, Ultimate A+ Night Cream is designed for those looking to refine texture and tone or support skin prone to congestion. With 0.1% Retinal (the next-generation form of Vitamin A), Niacinamide, and 2% Glycolic Acid, this formula delivers visible improvements while remaining gentle and well tolerated.

This unique combination supports smoother-looking skin, helps refine the appearance of pores and uneven tone, and promotes a more hydrated, balanced complexion.

Featuring:

Potent yet gentle formulation suitable for daily use
Helps improve the appearance of uneven tone and texture
Supports firmer, more supple-looking skin
Formulated with evidence-based ingredients known to enhance skin clarity

Note: Retinal is not suitable for use during pregnancy.

Shop ESK Retinal Collection

References

Why retinaldehyde (retinal) is the most effective form of vitamin A for aging skin

Retinal vs Retinoids: The Smarter Choice for Your Skincare Routine

How to Introduce Retinal into Your Skincare Routine

Retinal for Acne-Prone Skin: Can It Help Reduce Breakouts

The Science of Retinal (Retinaldehyde): Why It’s the Future of Skincare

Retinal for Pigmentation: How It Reduces Dark Spots and Evens Skin Tone

Retinaldehyde: Why it's the best skincare ingredient you've never heard of

Retinal for Sensitive Skin: A Gentle, Effective Anti-Aging Solution

The New Skincare Star: Why Retinal is Taking Over Retinol

Frequently Asked Questions

Find answers to common questions about our product

Yes, the two concerns overlap significantly. Retinal accelerates cell turnover, helping shift pigmented cells out of the skin faster. L-Ascorbic Acid (Vitamin C) helps neutralise the UV signal that triggers excess melanin production. Glycolic Acid, Lactic Acid as well as PHAs (Polyhydroxy acids) support surface renewal, improving uneven skin tone over time. Combining these actives with daily SPF gives you an approach that addresses both aging and discolouration simultaneously, which is why ESK's anti-aging products are also core to its pigmentation routines.

Mature and menopausal skin faces a dual challenge: accelerated collagen loss (driven by falling oestrogen) and a disrupted skin barrier which causes increased sensitivity and dryness. A strong routine includes a gentle cleanser, Vitamin C serum in the morning, a ceramide-rich moisturiser to support barrier function, retinal skincare product at night, and an SPF daily. ESK has dedicated collections for both Menopausal and Perimenopausal skin with products matched to these specific needs.

Yes, but choosing the right products for your skin is important. Sensitive skin doesn't mean you can't use evidence-based anti-ageing ingredients, it just means you may need to start with gentler formulations. For vitamin A, retinal (retinaldehyde) is generally better tolerated than retinol while still delivering excellent anti-ageing benefits. Many people can use retinal more comfortably, although those with very sensitive skin should still introduce it gradually. For vitamin C, L-ascorbic acid is the gold standard for improving photodamaged skin, but because it's formulated at a low pH, it can sometimes cause temporary stinging or irritation in sensitive skin. If your skin is more reactive, it might be better to avoid Vitamin C serums. The key to success is matching your skincare to your skin's current tolerance, not using the strongest products from day one. The ESK Skin Quiz can help identify the best anti-ageing routine for your skin type, sensitivity and experience with active ingredients.

The three ingredient groups with the strongest evidence for anti-aging are cell regulators, antioxidants and chemical exfoliants - in that order. In the cell regulator category, Vitamin A is by far the most studied and most effective ingredient across all anti-aging actives. Retinal (Retinaldehyde) is the form ESK uses because it is both highly effective (10-20x's more effective than Retinol) and non-irritating, even for sensitive skin. In the antioxidant category, L-Ascorbic Acid (Vitamin C) and Niacinamide (Vitamin B3) have the strongest evidence. For exfoliation, Glycolic Acid and Lactic Acid have the best clinical support. And the emerging evidence for Polyhydroxy acids make them a great option for sensitive skin. Daily broad-spectrum SPF sits above all of these: UV exposure is the primary driver of premature skin aging, and no active ingredient can outwork unprotected sun exposure.

Skin ageing is driven by two main processes: chronological ageing (the natural ageing process) and premature ageing, also known as photoageing.

Chronological ageing happens naturally over time as the skin produces less collagen, elastin and hyaluronic acid, and its ability to repair and renew itself slows. This leads to thinner, drier skin, fine lines and a gradual loss of firmness.

Premature ageing is caused by external factors, particularly cumulative UV exposure, which is responsible for up to 80% of visible facial ageing. UV damage breaks down collagen and elastin, leading to deeper wrinkles, rough texture, uneven pigmentation and loss of elasticity. Smoking, air pollution, poor sleep and diet can also contribute to premature skin ageing.

While we can't stop chronological ageing, we can slow and even improve many of the visible signs of UV skin damage. Most evidence-based skincare ingredients, including sunscreen, vitamin A (retinal), vitamin C and niacinamide, work by helping to prevent or repair the effects of photoageing.

The only form of Vitamin C with strong clinical evidence for anti-aging is L-Ascorbic Acid. Most brands use bonded derivatives like Magnesium Ascorbyl Phosphate and still call it Vitamin C on the label. But there is no evidence those alternatives actually work. The challenge with L-Ascorbic Acid is stability: it degrades when exposed to light and air. ESK formulates its Vitamin C products in airless, opaque packaging specifically to maintain stability and ensure the ingredient is still active when it reaches your skin.

Both are forms of Vitamin A but they work differently. Retinol requires a two-step conversion process in the skin before it becomes Retinoic Acid, the active form the skin actually uses. Retinal is one step closer, meaning it converts more efficiently and delivers faster results at lower concentrations. Retinal is also significantly better tolerated than Retinol, making it suitable even for sensitive skin. It is more expensive to produce, which is why most brands stick with Retinol, but the evidence for Retinal is strong and the irritation profile is in a different league. It is the only form of Vitamin A ESK uses.

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