Retinol: The Complete Guide
Retinol: The Complete Guide — a vitamin A derivative (a retinoid) and one of the most studied anti-ageing ingredients. It speeds cell turnover and stimulates collagen, helping to smooth fine lines, refine texture, unclog pores and even out tone.
Key points
- Retinol is converted in the skin to retinaldehyde and then to active retinoic acid; stronger prescription retinoids skip these steps.
- Start low and slow — a low percentage 2–3 nights a week — to build tolerance and limit the "retinisation" period of dryness and flaking.
- Always use it at night and pair with daily SPF, since retinoids can increase sun sensitivity.
- Avoid combining with strong acids or benzoyl peroxide in the same routine when starting out; pregnancy is a contraindication.
In this guide
- Retinal (Retinaldehyde)
- Retinyl Palmitate
- Retinyl Retinoate
- Tretinoin (Retinoic Acid)
- Adapalene
- Tazarotene
- Bakuchiol
- Hydroxypinacolone Retinoate (Granactive Retinoid)
- L-Ascorbic Acid
- Sodium Ascorbyl Phosphate
- Magnesium Ascorbyl Phosphate
- Tetrahexyldecyl Ascorbate
- Ascorbyl Glucoside
- Ethylated Ascorbic Acid
- Niacinamide (Vitamin B3)
Frequently asked
How long does retinol take to work?
Texture and tone often improve within 8–12 weeks, while collagen-related firming and fine-line benefits build over 6–12 months of consistent use.
Can I use retinol every night?
Eventually many people can, but it is best to build up gradually from 2–3 nights a week to avoid irritation, dryness and flaking.
Related topics
This is a foundational entry in the SYNC Skin Encyclopedia and is expanded over time. Educational information only — not medical advice.
