What is PHA in skincare?
PHA stands for polyhydroxy acid, the newest generation of chemical exfoliants. The two you will see on labels are gluconolactone and lactobionic acid.
Their molecules are considerably larger than AHAs, so they sit on the surface and exfoliate slowly rather than penetrating quickly. That makes them the gentlest option in the acid family – studies show anti-ageing results comparable to AHAs with noticeably less irritation.
What skin concerns do PHAs treat?
PHAs suit dullness, rough texture, uneven tone and early fine lines on skin that cannot tolerate glycolic or salicylic acid – including rosacea-prone, eczema-prone and generally reactive skin.
They are also humectants, so they hydrate as they exfoliate, and gluconolactone is an antioxidant that protects against UV-induced damage in laboratory models.
What ingredients are best paired with PHAs?
Because they are mild, PHAs layer comfortably with niacinamide, hyaluronic acid, ceramides and peptides, and they are often used to introduce exfoliation alongside a retinoid without overwhelming the barrier.
Follow with a moisturiser and daily SPF as with any exfoliant. If stronger acids have left your skin stinging or flushed, swapping to a PHA is usually the sensible step down. Take our Skin Quiz.
What is pigmentation?
Pigmentation refers to any change in the colour of the skin caused by melanin. Hyperpigmentation – the common form – means patches darker than your natural tone, including sun spots, melasma, freckles and the marks left behind after acne or injury.
Melanin is produced by melanocytes in the lower epidermis and handed to surrounding skin cells. When that process is over-stimulated or unevenly distributed, the result is a visible patch rather than an even tone.
What causes pigmentation?
Ultraviolet exposure is the single largest trigger, because UV directly activates melanin production as a protective response. Inflammation is the second: acne, eczema, friction, waxing, burns or harsh procedures can all leave post-inflammatory hyperpigmentation, which is more common and longer-lasting in deeper skin tones.
Hormonal change, certain medications, heat and genetics complete the picture. Without daily sun protection, treated pigment reliably returns.
What ingredients are best for pigmentation?
The most effective topicals work at different points of melanin production: vitamin C and niacinamide, azelaic acid, tranexamic acid, alpha arbutin, kojic acid and liquorice root extract.
Retinoids and gentle AHAs speed up turnover so pigmented cells clear faster. But broad-spectrum SPF worn daily is the ingredient that decides whether any of it holds – without it, results reverse within weeks. Take our Skin Quiz.