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 redness?
Facial redness is visible dilation of the small blood vessels near the skin’s surface. It ranges from transient flushing that comes and goes, to persistent erythema across the cheeks and nose, to fixed thread veins that stay visible all the time.
Redness is a symptom rather than a diagnosis. It can signal rosacea, irritation, an over-exfoliated barrier, eczema, an allergic reaction or simply reactive skin that responds strongly to heat and stress.
What causes redness?
Most persistent redness traces back to a compromised barrier and heightened nerve sensitivity. When the barrier thins, irritants penetrate more easily and the skin mounts an inflammatory response to things it would normally tolerate.
Common aggravators: over-exfoliation, high-strength actives used too often, fragrance and essential oils, hot water, alcohol, spicy food, sudden temperature change, sun exposure and stress. Trying to treat redness with more actives usually deepens it.
What ingredients are best for redness?
Prioritise calming and rebuilding over correcting. Niacinamide, azelaic acid, centella asiatica, green tea extract, liquorice root, allantoin, bisabolol and colloidal oatmeal all reduce visible inflammation.
Then repair the barrier with ceramides, cholesterol, fatty acids, glycerin, panthenol and squalane, and protect it with a gentle mineral SPF. Strip the routine back to cleanser, moisturiser and sunscreen for a few weeks before reintroducing anything active. Take our Skin Quiz.
