| Ceramides (1‑3‑6‑II complex) |
Replenishes depleted skin‑barrier lipids → reduces transepidermal water loss (TEWL) and soothes dry, compromised or eczematous skin |
Strong‑moderate Multiple 4‑ to 8‑week RCTs show significant increases in hydration and barrier recovery in both healthy volunteers and dermatitis patients. (Wiley Online Library, Cosmoderma, PMC) |
Extremely well‑tolerated; allergic reactions are rare. Pair with humectants/occlusives for extra hydration, but no special restrictions needed. |
| Hyaluronic acid (multi‑weight) |
Powerful humectant that binds up to 1,000× its weight in water → immediate plumping, smoother texture, reduced fine lines |
Strong (hydration), moderate (anti‑ageing) Topical and oral RCTs report ≥50 % sustained hydration boosts and visible texture improvements within 6 weeks. (PMC, PMC, PMC, MDPI) |
Very low irritation risk. In very low‑humidity climates it can pull water from skin, so seal with an emollient. Injectable HA side‑effects (bruising, necrosis) don’t apply to cleansers. (NCBI) |
| Niacinamide (vitamin B3) |
Multi‑tasker: strengthens barrier (↑ ceramides), fades hyper‑pigmentation, calms acne/rosacea inflammation, improves fine lines |
Strong 4 % niacinamide outperformed hydroquinone for melasma; other trials show reduced redness, sebum and pigmentation after 8–12 weeks. (PMC, PMC, MDPI, SELF) |
Generally non‑irritating up to 10 %. Rare users report transient redness; patch‑test high‑strength (>10 %) products. Avoid layering at very high pH (>7) to prevent conversion to flush‑inducing niacin. (Allure) |
| Salicylic acid (β‑hydroxy acid) |
Keratolytic & comedolytic: dissolves inter‑cellular “glue” in the stratum corneum → unclogs pores, smooths KP bumps, controls mild acne |
Strong Decades of clinical use; contemporary reviews confirm efficacy comparable to benzoyl peroxide for mild‑to‑moderate acne with better tolerability. (PMC, MDPI, Wiley Online Library) |
May cause dryness, stinging or mild peeling; start slowly and moisturize. Contra‑indicated if allergic to salicylates or for extensive use in late pregnancy/infants. Over‑exfoliation can weaken barrier. (Health) |
