Peptides in Skincare: What They Actually Do — and the Best Korean Serums to Try

Mar 25, 2026 Sena Lee

Peptides have quietly become one of the most recommended ingredients in skincare — not because they went viral, but because they genuinely work. Unlike trend-driven actives that peak and disappear, peptides have decades of research behind them and a growing reputation as the smarter, gentler approach to anti-aging.

Here's what you need to know, and the four products worth adding to your routine.

What Are Peptides?

Peptides are short chains of amino acids — the building blocks of proteins like collagen and elastin, which keep skin firm, plump, and structurally intact. From your mid-twenties, collagen production drops by roughly 1% each year. By the time fine lines and loss of firmness become visible, the decline has been happening quietly for years.

When applied topically, peptides act as messengers, signalling the skin to produce more collagen and elastin. Some relax the micro-muscle contractions that cause expression lines to deepen. Others strengthen the skin barrier or improve moisture retention. The result is firmer, smoother skin — with none of the irritation that comes with retinoids or acids.

Peptides vs. Retinol: Do You Need Both?

Retinol is highly effective but comes with an adjustment phase — peeling, sensitivity, and dryness are common. Peptides work differently: they support the skin's own repair processes from within, with no irritation risk and no downtime. They're suitable for all skin types, including sensitive and barrier-compromised skin.

The smartest approach is to use both. Peptides in the morning to firm and protect; retinoids at night to resurface and renew. If your skin can't yet tolerate retinoids, peptides are the best evidence-backed alternative to start with. You can explore Nuriglow's full anti-aging collection here.

How to Use Peptides in Your Routine

Apply your peptide serum after cleansing and toning, before moisturiser. Use morning and evening for consistent results — peptides work cumulatively, and most people notice a real difference in firmness and texture after four to six weeks.

One thing to note: avoid applying strong acids (AHAs, BHAs) at the exact same time as peptides, as high-acid environments can degrade some peptide molecules before they absorb. Use them at different times of day, or on alternating days. Peptides pair beautifully with niacinamide, hyaluronic acid, and PDRN.

Our Peptide Picks at Nuriglow

We've chosen four products from the Nuriglow Peptides collection — each one targeting a different concern, at a range of price points.

1. PURCELL 82% High Dose Peptide Formula — $42

→ Shop on Nuriglow Best for: Deep firming, lifting, all skin types including acne-prone

The standout anti-aging formula in the collection. Built around an 82% concentration of fermented Hexapeptide-11 — a peptide complex made more bioavailable through a fermentation process that breaks molecules down for better skin absorption — this serum also contains Palmitoyl Tripeptide-5 (a signal peptide clinically linked to collagen production) and hydrolyzed collagen to visibly plump and smooth. Clinical testing found the formula increases collagen levels by 40% after just 3 days of use. The texture is weightless and water-like, absorbing immediately with no residue. Free from harmful ingredients and safe for acne-prone skin.

Key ingredients: Saccharomyces/Hexapeptide-11 Ferment Filtrate Extract (82%), Palmitoyl Tripeptide-5, Hydrolyzed Collagen, Adenosine Size: 30ml | Use: Apply to bare skin after cleansing, before toner and moisturiser. AM and PM.

2. SUNGBOON EDITOR Silk Peptide Intensive Lifting Ampoule — $34 (on sale from $38)

→ Shop on Nuriglow Best for: Sagging skin, visible lifting, deep wrinkles, mature skin

The most clinically validated option in the edit. This ampoule uses silk water (instead of plain purified water) as its base, delivering amino acids and proteins directly to the skin with every application. The formula contains 13 types of peptide complex — including Acetyl Hexapeptide-8 (relaxes expression-line-causing muscle contractions), Copper Tripeptide-1 (barrier repair and collagen support), and Palmitoyl Pentapeptide-4, one of the most well-researched signal peptides available — alongside collagen threads in two molecular sizes for both surface smoothing and deeper structural support. Tested across 19 clinical assessments with measurable improvements in skin age, wrinkle count, and elasticity. Delivers 72-hour hydration and has been dermatologically tested for sensitivity.

Key ingredients: Silk Water (48% base), 13-Peptide Complex (incl. Acetyl Hexapeptide-8, Copper Tripeptide-1, Palmitoyl Pentapeptide-4), Collagen Threads, Niacinamide, 5 forms of Sodium Hyaluronate, Volufiline Size: 35ml | Use: Remove cap, insert syringe, dispense and apply AM and/or PM before moisturiser.

3. Smilebloom KKOCH Hero Complex Serum — $24

→ Shop on Nuriglow Best for: Acne-prone skin, dark spots, sensitive skin, beginners to peptide skincare

The most versatile pick in the edit — and the best value. This lightweight gel serum combines 85% snail mucin with Oat Peptide (a plant-based peptide that reduces fine lines and surface irregularities), Vegan Collagen Extract, and 4% Niacinamide. It's clinically proven to visibly fade dark spots in as little as two weeks, while the niacinamide and peptide combination helps balance sebum and minimise pores. Non-sticky, fast-absorbing, and completely free from artificial fragrance, silicones, parabens, and mineral oils — meeting full clean beauty standards. At $24 for 50ml, it's exceptional value for what it delivers.

Key ingredients: Snail Secretion Filtrate (85%), Oat Peptide (Avena Sativa), Vegan Collagen Extract, 4% Niacinamide, Sodium Hyaluronate, Panthenol Size: 50ml | Use: Apply after toner, before moisturiser. AM and PM.

4. Beplain Mung Bean Pore Tight-Up Serum — $24

→ Shop on Nuriglow Best for: Enlarged pores, oily and combination skin, sebum control

Proof that peptides aren't just for fine lines. This serum is built around Beplain's proprietary Mung Bean Peptide™ — low-molecular peptides extracted from mung beans at low temperature to preserve their natural cooling properties. These small molecules signal the pore walls to firm up and maintain their elasticity, addressing the gradual loosening of pore structure that makes them appear larger over time. The formula also contains POMEG-PORE™ (a pomegranate flower complex for sebum reduction), Acetyl Hexapeptide-8 for expression line smoothing, and niacinamide for brightening. The gel-to-water texture absorbs instantly and feels cooling on application. Clinically tested across seven pore improvement markers — number, volume, depth, area, texture, and pore line — with improvements shown across all seven.

Key ingredients: Mung Bean Peptide™, POMEG-PORE™ (Pomegranate Flower Extract), Acetyl Hexapeptide-8, Niacinamide, Hyaluronic Acid, Adenosine Size: 30ml | Use: Apply 2–3 pumps after toner, pat gently to absorb. AM and PM.

→ Browse the full Nuriglow Peptides collection

FAQ: Peptides in Skincare

Q. What do peptides do for skin?
A. Depending on their type, peptides stimulate collagen and elastin production, relax the muscle contractions behind expression lines, protect existing collagen from breakdown, and improve moisture retention — resulting in firmer, smoother, and more resilient skin.

Q. When should I start using peptides?
A. The earlier the better. Starting in your mid-to-late twenties means you're supporting collagen before visible decline begins. Prevention is significantly more effective than reversal.

Q. Can I use peptides with retinol?
A. Yes — and it's one of the best combinations in skincare. Use peptides in the morning and retinoids at night for a comprehensive anti-aging approach that targets two different mechanisms.

Q. Are peptides safe for sensitive skin?
A. Yes. Peptides work with the skin's natural processes rather than forcing a reaction, making them one of the safest active skincare categories. Suitable for all skin types, including sensitive and reactive skin.

Q. How long does it take to see results from peptides?
A. Most people notice improved texture and hydration within two to three weeks, with more visible changes in firmness and fine lines after four to six weeks of consistent daily use.