What is DHA in skincare?
DHA in skincare means dihydroxyacetone, a simple three-carbon sugar produced by fermenting glycerin. It is the active ingredient in essentially every self-tanner on the market, and has been used that way since the 1960s.
It should not be confused with docosahexaenoic acid, the omega-3 fatty acid that shares the abbreviation. Reviews of topical dihydroxyacetone cover its chemistry, performance and safety profile in sunless tanning products.
What skin concerns does DHA treat?
DHA does not treat a skin concern so much as change colour. It reacts with amino acids in the outermost dead skin cells through the Maillard reaction – the same browning chemistry as toast – producing pigments called melanoidins.
Because only surface cells are affected, the colour develops over two to four hours and fades in five to seven days as those cells shed. Crucially it offers almost no UV protection, so sunscreen is still required. Some research notes free-radical generation in treated skin, another reason to wear SPF over it.
What ingredients are best paired with DHA?
Exfoliate and moisturise dry areas – knees, elbows, ankles – before applying, since DHA grabs harder where skin is thicker and gives a patchy result otherwise.
Antioxidants such as vitamin C and E are sensible alongside it. Avoid applying it immediately after AHAs or retinoids, which speed up cell turnover and shorten the tan, and keep it away from freshly waxed or shaved skin. Take our Skin Quiz.
What is cystic acne?
Cystic acne is the most severe form of inflammatory acne. Instead of surface pimples, it produces deep, tender nodules and fluid-filled cysts that sit under the skin, often without ever coming to a head.
It happens when a blocked follicle ruptures deep in the dermis and spills sebum, keratin and bacteria into surrounding tissue, triggering a strong immune inflammatory response. Because the damage is deep, cystic acne is the type most likely to scar.
What causes cystic acne?
The same four factors behind all acne, amplified: excess sebum, abnormal shedding inside the follicle, overgrowth of Cutibacterium acnes, and inflammation. Androgens drive sebum production, which is why cystic acne often tracks with hormonal cycles, PCOS or puberty.
Genetics strongly influence severity, and stress, high-glycaemic diets, occlusive products and picking at lesions all make it worse. Squeezing a cyst pushes the contents deeper and reliably increases scarring.
What ingredients are best for cystic acne?
Cystic acne genuinely warrants a dermatologist – oral treatment is often needed. Alongside that, topical retinoids are the most useful over-the-counter active, because they work on the plug before it ruptures.
Benzoyl peroxide reduces bacterial load, azelaic acid calms inflammation and post-acne marks, and niacinamide helps redness without irritation. Keep the rest of the routine gentle and barrier-focused – harsh scrubs and drying alcohol make deep lesions angrier. Take our Skin Quiz.
