PM Routine

Retinol Serum, Explained: What "1% Retinol & Peptides" Actually Does

Retinol has the strongest evidence base of almost any ingredient in skincare — and also the worst reputation for irritation. Both things are true at once, and the gap between them usually comes down to formulation and pacing, not the ingredient itself.

What Retinol Actually Does

Accelerated cell turnover — improves texture, fades the look of post-acne marks, keeps pores clearer over time.
Collagen stimulation — signals fibroblasts to increase collagen output, the mechanism behind its long-term effect on fine lines and firmness.
Normalized pigment production — helps even tone through a different pathway than vitamin C.

Meaningful change typically shows up over 8–16 weeks of consistent use — retinol is a compounding ingredient, not a quick fix.

Retinol vs. Retinyl Palmitate: Why the Ester Form Matters

Pure retinol converts to retinoic acid in two steps inside the skin — effective and relatively fast, but the most likely to cause redness and flaking early on. Retinyl palmitate is an ester of retinol that needs an extra conversion step, which makes it meaningfully gentler and slower-acting — exactly why it's common in beginner-friendly formulas.

Neither is objectively better — it's a tradeoff between speed and tolerance. What matters is knowing which one is actually behind the percentage on the box.

Why "1%" Doesn't Tell the Whole Story

Because ester forms are weaker gram-for-gram than pure retinol, a formula built on retinyl palmitate at 1% is generally much gentler in real-world use than a 1% pure retinol product — even though the number looks identical. Check the ingredient name, not just the percentage.

Why Retinol Is Rarely Formulated Alone

Peptides & collagen — support skin's structural proteins while it adjusts.
Niacinamide — calms and strengthens the barrier, and reduces retinol's irritation potential when combined in one formula.
Ceramides — replace lipids lost to increased turnover.
Hyaluronic acid — adds back water content, since retinol can leave skin feeling drier in the first few weeks.

The "Retinol Purge" and How to Avoid It

Start at 2 nights a week, not nightly — give skin a full week before increasing.
Buffer if needed — a light moisturizer before retinol slows absorption and reduces irritation without meaningfully reducing effect.
Increase gradually toward nightly use over 4–6 weeks.
Scale back at the first sign of persistent redness or peeling beyond mild flaking.

Non-Negotiable: Sunscreen the Next Morning

Retinol increases skin's photosensitivity. Skipping sunscreen the morning after undercuts the ingredient's benefits and raises the risk of sun damage and pigmentation. If there's one rule to take seriously here, it's this one.

Building a Routine Around It

Retinol belongs in a PM routine — sunlight degrades it and raises irritation risk. Don't stack it with exfoliating acids or high-strength vitamin C in the same application; a common, low-friction structure is vitamin C in the morning, retinol at night. Moisturize afterward to offset dryness.

Who Should Be Cautious

Pregnant or breastfeeding individuals are generally advised to avoid retinoids altogether — this is a case where a conversation with a doctor isn't optional. Very reactive or eczema-prone skin should introduce it slowly, starting with a gentler ester form if needed.

el Sol's Cela Serum is formulated with 1% Retinol & Peptides, Hyaluronic Acid, and Niacinamide — built around the buffering logic above, and designed to sit at the end of a PM routine, after Bask has done its work in the morning.