Never question skincare forum die-hards. The armchair experts that flock to Reddit know their shit, and they know retinol inside and out: the dos, the don’ts and the deep, almost magical properties that come with one of the industry’s must effective ingredients.

A fat-soluble form of vitamin A, its entry to the business of looking younger in the 1970s was no fad. It’s stuck around. And that’s because, unlike a lot of the inexact science pushed by ‘age-defying’ products, it actually works. By stimulating cell production (‘proliferation’ if we’re to go by the proper term), retinol increases collagen levels to replenish the skin. Your face looks younger, smoother and plumper as a result.

That doesn’t mean you buy a barrel and slap on the high-grade, though. Retinol is a cold mistress. She needs a bit of patience. It takes time to build up to the stronger concentrations, and rushing retinol can result in adverse reactions (peeling, reddening, drying – all the gross stuff). In addition, retinol doesn’t always play nice with other active ingredients in your skincare routine. You need to know what you’re doing, in other words.

And so, to define exactly what it is, why you should be buying it and the best retinol-based products out there, here is Alexander Johnston of pharmacist John Bell & Croyden.

What Is Retinol?

“Retinol is basically a topical vitamin A, which belongs to the retinoid family. Retinol is the strongest retinoid that you can buy without a prescription. Weaker retinoids, such as retinyl acetate and retinyl palmitate, are often found in skin care for more sensitive skin, but the effects are slower and less dramatic.”

What Does Retinol Do?

“Basically, retinol resurfaces the skin by speeding up cell renewal and promoting the production of collagen. This is why you see the softening of wrinkles and fine lines, as the retinol activates the plumping effect collagen, while revealing a fresher complexion. In a more technical sense, retinoids communicate with the cells to encourage them to renew faster than usual, which helps to treat sun-damaged skin, age spots, pigmentation issues and high colour. Using retinol actually encourages the production of red blood vessels in the skin which, in turn, is what helps even out skin tone.”

Who Is Retinol Best For?

“Retinol can be used by anyone who wants to improve their skin texture, has sun damage, acne or pigmentation issues. There are lots of different strengths and variants available, so it is always best to seek advice from a skincare expert (or at least read a few reviews online) before diving in. I would always recommend that you start slowly, maybe once or twice a week to begin with, building up to nightly use. The thing with retinol is that it takes regular use for maybe four to six weeks to see huge results, although there are products on the market that are buffered with other ingredients, such as hyaluronic acid and vitamin E, which can have a more instant effect and can be kinder on the skin, allowing you to jump right into daily use.”

Are There Any Risks With Retinol Use?

“Unbuffered retinol can cause sensitivity when first used, but as long as you start with a lower concentration and work up to the higher strengths it is usually not a problem. Buffered retinols are often kinder on the skin, as they have additional ingredients that help calm and soothe the skin. It is recommended that if you use retinol at night, you also use a good day cream, with a minimum SPF of 30, as the skin can become more sensitive.”

What Shouldn’t You Use With Retinol?

Given retinol’s photosensitivity, try to avoid products with vitamin C. That’s because it acts as a barrier to the skin, and retinol does the opposite in repairing collagen levels. To give your face a bit of breathing room, apply vitamin C-based products in the morning and retinol before sleep in the evening.

Also swerve salicylic, glycolic and lactic acids, also known as AHA/BHA acids. They all work as exfoliants and as such, can irritate and dehydrate your skin as they get to work. Retinol, as an ingredient that can make everything a little more sensitive, may magnify these downsides.

What Are The Best Retinol-Based Products?

Super Retinol 1% + vitamin C night renewal moisturiser

Super Retinol, it says! And it’s not a liar. This combination of the good stuff with vitamin C means that skin is given extra hydration to keep moisture locked in, which is especially helpful if you’re a little sensitive.

The Ordinary 1% retinol in squalane

There’s a reason The Ordinary is a multimillion-pound cult brand. It’s fuss-free, to the point, and offers advanced-grade cosmetics at an entry-level price. The 1% retinol – a safe percentage to start at – is no exception, and adds an oily substance called squalane that helps to smooth and moisturise the skin.

Indeed Labs retinol refacer

The best sort of retinol has three hands. Labs’ retinol re-facer is a nightly product that packs in added levels of bakuchiol and a peptide. Both are antioxidants. Both detoxify your skin while retinol renews the stuff it’s made of.

Medik8 crystal retinal 10

You’re playing with the big boys now. Medik8’s crystal retinal 10 is premier league-level grooming with a higher dose of retinol. That means it’s more effective, but this should come into your rotation a couple of months in.