Let's talk about retinol (baby). A vitamin A derivative, retinol is converted into retinoic acid at a cellular level, which has potent skin-reparative and anti-ageing benefit, but is oft-maligned because of its side effects. Unlike AHAs, which brighten skin by dissolving the bonds that bind dulling dead cells to its surface, retinol re-energises lazy fibroblasts - stimulating synthesis of skin-essential 'scaffolding' - the collagen, hyaluronic acid and elastin that keep skin smooth and supple.

Retinol accelerates turnover - maintaining the natural regenerative processes we take for granted in our teens and early 20s. As skin cells become sluggish (sometime around 25), retinol helps to keep things ticking over - however, this can trigger a slight 'peeling' effect. Redness and flakiness went hand-in-hand with retinoids until relatively recently, often acting as a deterrent to their use (obviously). However, with modern technology and clever, encapsulated formulations (as well as milder strengths for those who're tentative), it's easier and easier to find a perfect daily formulation.

Retinol also increases sun sensitivity, which is why most vitamin A products are positioned as overnight treatments. You'll find a wealth of night creams, bedtime 'peels' and overnight 'facials' laced with vitamin A, which works its unencumbered, skin-perfecting magic while your slumber.

And it isn't just an age-defying powerhouse. It's also brilliant for blemish-prone and acneic complexions, as well as those with dulled, pigmented or pock-marked visages. By 'bothering' cells into action, it stimulates skin's healing and reparative processes to 'densify' while fading scars and fortifying fragile tissue.

The 'head girl' of the anti-ageing ingredients league, there are few things retinol doesn't do - it strengthens, plumps, elasticises, brightens, unifies and 'youthifies' in one fell swoop - ideal as a preventative measure, as well as a potent, time-rewinding treatment.

Pioneering 'clean-clinical' skin care, Drunk Elephant's latest, impatiently-awaited launch is the brand's first foray into the 'retinol realm'. Bridging a perceived gap in the brand's potent age-defying arsenal, {A-Passioni Retinol Cream} has a comforting, silicone-free formula with 1% retinol (it's sufficiently gently for use in the day time) - buffered by powerhouse plant extracts, peptides and fatty acids to guarantee maximum, youth-boosting benefit with zero side-effects.

Pixi's eagerly-anticipated {Retinol Tonic} pairs time-released, encapsulated retinol with soothing jasmine flower extract to deliver a quick, youth-preserving boost to sleepy cells. A nightly post-cleanse step, this purple cocktail is the perfect introduction to this potent powerhouse - sufficiently gentle for beauty beginners, it's sure to become a fixture of your bedtime regime.

Sunday Riley's {Luna Sleeping Night Oil} partners retinol with blue tansy - a calming plant extract which quickly combats signs of sensitivity. With an array of rave reviews, this product is an ideal introduction for those keen to start a 'youth-preserving' ritual - as well as those who're struggling with myriad skin issues.

{VERSO} is a revelation in retinol, thanks to its signature 'Retinol 8' complex - the 'first high dose vitamin A derivative that can be used safely in the daytime'. The '8' stands for 'eight times more effective' than typical retinol in the same quantity, which means maximum gain with minimum upset.

Or, opt for The Ordinary's {Advanced Retinoid 2%} which - at only £8!! - is the perfect 'no frills' formulation for anyone looking to jump on the retinoid bandwagon. Apply in the evening, sandwiched between cleanser/toner and night cream/oil - it's a treatment serum and remarkably potent, so build up your tolerance gradually. Use on alternate evenings to begin with, gradually increasing frequency to maximise the skin-transforming benefits.