The Ordinary Retinol 0.2% in Squalane, Gentle Retinol Serum for the Face That Is Anti-Aging

What is the difference between retinol and retinoids?

Retinoids is the umbrella term for all vitamin A derivatives, including prescription-strength tretinoin, retinaldehyde, and over-the-counter retinol. Retinol must be converted by the skin into retinoic acid before it is active, which makes it gentler but also less immediately potent than prescription tretinoin. Prescription retinoids work faster and more dramatically but carry a higher risk of irritation.

What are vitamin C derivatives and are they as effective?

Vitamin C derivatives like ascorbyl glucoside, sodium ascorbyl phosphate, and ascorbyl tetraisopalmitate are stabilized forms that convert to active vitamin C in the skin. They are gentler and much more stable than L-ascorbic acid, making them good options for sensitive skin or those who find pure vitamin C irritating. However, conversion efficiency varies and they are generally considered slightly less potent than the pure form.

What is the difference between AHA and BHA?

AHAs (alpha hydroxy acids) are water-soluble exfoliants that work on the skin's surface to dissolve the bonds between dead skin cells, improving texture, tone, and radiance. BHAs (beta hydroxy acids) are oil-soluble, meaning they can penetrate into pores and dissolve sebum and debris, making them ideal for acne-prone and oily skin. Both are chemical exfoliants, but they target different concerns.

What are PHAs and are they gentler than AHAs?

PHAs (polyhydroxy acids) like gluconolactone and lactobionic acid are a newer generation of chemical exfoliants with larger molecules that cannot penetrate deeply into skin. This makes them significantly gentler than AHAs, with comparable exfoliating benefits and the added bonus of humectant and antioxidant properties. PHAs are ideal for rosacea-prone, sensitive, or eczema-prone skin that cannot tolerate traditional AHAs or BHAs.