Retinol has for decades stood as a cornerstone in skincare. From skin aging to acne, Retinol and its derivatives play a key role in skin health and quality. Due to these powerful effects, Retinol is widely available in various forms and strengths. This choice can cause confusion in term of what the different Retinol percentages mean and how they relate to Retinoids. In this guide, we explain the different strengths and percentages of Retinol available. We also discuss what the equivalent Retinol percentages are for other popular Retinoids like Retinyl esters, Retinal and Retinoic acid.
What’s the Difference Between Retinol & Retinoids?
Retinol is vitamin A in its pure molecule form. When you apply it to your skin, your cells convert Retinol into Retinaldehyde Retial) and then Retinoic acid. Retinoic acid is the active form of Retinol. It stimulates skin cells to increase cell turnover, regenerate and produce more collagen. Whilst Retinol is the pure form for Vitamin A, it also has a number of derivatives. These are collectively known as Retinoids. The strengths of these compounds compared with Retinol depending on their place in the hierarchy.
- Retinyl esters such as Retinyl palmitate are the gentlest form of Retinol. They require a three-step conversion process to become active. First, Retinyl esters convert to Retinol, then to Retinaldehyde then finally to Retinoic acid. This multi-step process reduces the immediate potency and potential side effects. As such, Retinyl esters ideal for sensitive skin or those new to retinoids.
- Retinal, also known as Retinaldehyde, is a direct precursor to Retinoic acid and so only needs one conversion step. Due to this, Retinal is more powerful than Retinol and Retinyl esters but is generally better tolerated than Retinoic acid.
- Adapalene is a synthetic Retinoid which binds directly to Retinoid receptors in the skin. This means it basically skips the conversion process. It is mainly used to treat acne. Adapalene is usually considered more potent than Retinol or Retinal but with fewer irritative effects. Adapalene is available by prescription in the UK.
- Retinoic acid (aka Tretinoin or Retin-A) is available by prescription only in the UK. It is the most potent form of vitamin A and works directly on the skin without the need for conversion. Due to this, Retinoic acid is a powerful agent against severe acne, scars, hyperpigmentation and prominent signs of aging. However, its potency also means it can cause notable side effects such as redness, peeling and sensitivity.
Guide to Retinol Strengths
Retinol in most of the world (except the EU) is available in concentrations ranging from 0.1% to 1%. It’s really important to understand these Retinol percentages as they guide the product’s safety and its effect on the skin. It’s also useful to help you look beyond marketing and choose the right retinol strength for you. As a general rule, high strength Retinol generally refers to the highest percentage. In the UK this is anything that contains concentrations at or near 1%. Conversely, low strength Retinol generally refers to percentages below 0.3%.
Choosing the right Retinol strength to start on is a balance between achieving optimal results without overwhelming or injuring your skin. If you’re a beginner or have skin of colour, then a good guide is to start with lower Retinol percentages (around 0.1% to 0.3%) and frequency. You can gradually progress to nightly use and move to the highest strength Retinols as your skin builds tolerance. If you have sensitive skin or Rosacea, you may be better off starting with the more gentle Retinyl esters.
Equivalence of Retinol Strength for Retinoids
What a lot of people don’t realise is that these strengths strictly refer to Retinol products only which if you’ll remember is the pure form of Vitamin A. Sadly, the percentage of Retinol does not directly translate to Retinoids. This can make it confusing if you want to switch to a different Retinoid or start with something that isn’t Retinol. Here’s a simple guide to find the equivalent Retinol strength or percentage for different Retinoids to help with conversion between them:
- Retinyl esters are normally about 20% as strong as Retinol due to their inefficient conversion to Retinoic acid. Roughly speaking, a product with 1% Retinyl palmitate is roughly equivalent to 0.2% Retinol.
- Retinal is approximately at least 10 times stronger than Retinol though this difference tends to translate into faster effects rather than greater benefits. As such a 0.05% Retinal product may offer benefits comparable to a 0.5 to 1% Retinol product.
- Adapalene functions differently to Retinol and is more effective than it for acne at any strength. As such it’s not possible to directly compare strengths. However, in general terms 0.1% Adapalene might be roughly comparable in its efficacy to a highest strengths of Retinol (around 0.5% to 1%). 0.3% Adapalene is stronger than any over-the-counter Retinol.
- Retinoic acid is directly effective without conversion. Whilst direct conversion to equivalent strength isn’t possible, Tretinoin 0.1% is generally considered 20x more potent than the highest over the counter Retinol and 10x stronger than the highest strength Retinal. This means that even at very low concentrations (such as 0.025%), Tretinoin is more effective and provides faster results than the highest Retinol strength (1%) and Retinal (0.1%).
Navigating the world of Retinol and its derivatives is exciting but also complex. However, the secret is to arm yourself with the right knowledge so you can choose the best products and start on the right protocol for your skin type, concerns and goals. Regardless of whether you opt for Retinol or an equivalent, always remember that consistency and patience are the most important factors for success. Be guided by this when deciding on which Retinol or Retinoid percentage to start on. Don’t forget to take a holistic approach to your skin health and always consult with a dermatologist or medical professional if you have any underlying skin or medical problems.
We are super passionate about skin health and personalised skincare at City Skin Clinic. Through our virtual skin clinic, our doctors offer safe and effective prescription-strength treatments including Tretinoin and Hydroquinone. We treat skin conditions like acne, hyperpigmentation, melasma and skin ageing. To get start your personalised skincare protocol, book a virtual video consultation or use our online consultation form. The journey towards great skin starts here.