The Power — and Danger — of Actives
Skincare "actives" are ingredients that create a measurable change in the skin — exfoliating, increasing cell turnover, brightening pigmentation, or stimulating collagen. They are also the ingredients most likely to cause irritation, sensitivity, or compromised skin barriers when used incorrectly. The good news: with a little knowledge, you can harness their benefits safely.
Understanding the Main Actives
- AHAs (Alpha Hydroxy Acids): Glycolic acid, lactic acid, mandelic acid. Surface exfoliants that dissolve the bonds between dead skin cells. Great for dullness, uneven texture, and mild pigmentation.
- BHAs (Beta Hydroxy Acids): Salicylic acid. Oil-soluble exfoliant that penetrates into pores. Ideal for acne, blackheads, and oily skin.
- Retinoids: Retinol, retinal (retinaldehyde), tretinoin. Vitamin A derivatives that accelerate cell turnover. The gold standard for anti-ageing and acne.
- Vitamin C (Ascorbic Acid): Antioxidant and brightening agent. Inhibits melanin production and protects against UV-induced oxidative stress.
- Niacinamide (Vitamin B3): Anti-inflammatory, pore-minimising, brightening. One of the most compatible actives.
- Peptides: Signal skin to produce more collagen. Gentle and generally compatible with most other actives.
The Layering Rules
Rule 1: Lowest pH First
AHAs and BHAs work at a low pH (typically below 4). They should be applied to clean, dry skin before higher-pH products like moisturisers. If you apply them after a high-pH moisturiser, you reduce their effectiveness.
Rule 2: Don't Mix What Fights
Some combinations actively work against each other or create too much irritation:
| Combination | The Problem | What to Do Instead |
|---|---|---|
| Retinol + AHA/BHA | Too much exfoliation; barrier damage | Use on alternate evenings |
| Retinol + Vitamin C | Different optimal pH; potential irritation | Vitamin C in AM, Retinol in PM |
| AHA + BHA together (high concentrations) | Over-exfoliation | Use one at a time; alternate days |
| Benzoyl Peroxide + Retinol | Benzoyl peroxide oxidises retinol, rendering it less effective | Use at separate times |
Rule 3: Niacinamide Is the Peacemaker
Niacinamide pairs well with almost everything — AHAs, BHAs, vitamin C, and even retinol. It's particularly useful layered after exfoliating acids to calm any potential redness. The old belief that niacinamide and vitamin C cancel each other out has been largely debunked at typical cosmetic concentrations.
A Safe and Effective Weekly Schedule
If you're using multiple actives, a rotation approach minimises irritation risk:
Morning Routine (Daily)
- Cleanser
- Vitamin C serum
- Niacinamide (optional)
- Moisturiser
- SPF 50
Evening Routine — Alternating
- Monday / Wednesday / Friday: Retinol or retinoid
- Tuesday / Thursday: AHA or BHA exfoliant
- Saturday / Sunday: Rest — moisturiser and gentle barrier repair only
Signs You've Over-Done It
Your skin will tell you when you've pushed too hard with actives. Watch for:
- Persistent redness or a stinging sensation that doesn't settle within minutes
- Skin that feels raw, tight, or paper-thin
- Increased breakouts (a sign of compromised barrier, not purging)
- Peeling and flaking that doesn't improve with moisturiser
If any of these occur, pause all actives, focus on barrier repair (ceramides, panthenol, gentle fragrance-free moisturiser), and reintroduce slowly — one product at a time.
Slow and Steady Wins
The temptation to use every powerful ingredient at once is understandable, but patience is rewarded in skincare. Introducing actives slowly, observing how your skin responds, and building a routine you can sustain for months — not days — is what actually delivers visible, lasting results.