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Trend Watch · Issue 004 · 01 December 2025

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Issue 004

Mandelic acid is having a moment. We agree, with footnotes.

The case for mandelic in skin of colour is stronger than the case for glycolic. Here is the evidence.

Signed — Dr. Paul

Verdict № 01
01
Tier A

Mandelic 10% serums

Holds Up

Mandelic acid's larger molecular weight (152 Da, vs glycolic's 76) means slower, gentler stratum-corneum penetration — historically dismissed as 'less effective' by AHA enthusiasts, now re-evaluated as exactly the property that makes it the better choice for skin of colour, sensitive types, and acne-prone surfaces. Three new Indian RCTs through 2025 have shown 10% mandelic at pH 3.4–3.6 producing comparable comedonal-acne and PIH endpoints to glycolic at lower irritation rates.

Bottom line

The default AHA for melanin-rich and reactive skin. Tier A on its own merits, not by deference.

Verdict № 02
02
Tier B

Mandelic + lactic blends

Partly True

Combination AHA serums (mandelic + lactic, often + a small percentage of salicylic) chase a 'wider exfoliation envelope' that the literature only partially supports. The blend formulations are typically pH-managed reasonably well, but the additive endpoints often plateau at what 10% mandelic alone delivers. Not bad — the best of these are very tolerable — but rarely meaningfully different from a clean single-acid serum.

Bottom line

Tolerable, marginally additive. Pay for the formulation only if texture differs meaningfully.