Stop overthinking this. You use retinal at night. Period. The whole “can I use it in the morning?” thing is just brands trying to sell you more product.
Here’s the thing nobody tells you: retinaldehyde is photounstable in formulation. It literally degrades faster in light. So that morning application? You’re wasting half the potency before it even touches your skin.
Southo’s Fermented Retinaldehyde Night Renewal Serum. $68 for 30ml. The claim that hooked me: “retinol results without the purge.” Yeah, sure. But I tried it anyway because the fermentation angle sounded less irritating than straight retinal.
Fermentation tech
They ferment the retinal with lactobacillus — supposedly makes it gentler on the skin barrier. I call BS-adjacent marketing, but my face didn’t peel, so maybe?
Time-release delivery
Sits on skin for about 8 hours before fully converting to retinoic acid. Means you can’t wash it off after 20 minutes and expect results.
No fragrance
Actually none. Smells like slightly sour nothing. Weirdly refreshing after all those rose-scented retinols.
Retinaldehyde is the star — it’s one conversion step away from retinoic acid, so it works faster than retinol but with less drama. The fermentation process supposedly breaks it down into smaller molecules for better absorption. Or it’s just a fancy way to say “we added yogurt bacteria.”
- Fermented Retinaldehyde (0.1%): Converts to retinoic acid in one step — faster than retinol, less angry than prescription
- Niacinamide (2%): Calms the redness retinal tries to cause
- Ceramide NP: Patches up your barrier while retinal tears it down
- Tocopherol: Vitamin E — mostly here to keep the formula stable, not save your skin
Thin, watery serum. Absorbs in about 15 seconds — no tacky residue. I slathered it on, waited 2 minutes, then slapped moisturizer over it. First night felt like nothing. Second night: slight tingle around my nose. By night 4, I was convinced it was a dud.
Week 2 threw me. Woke up with that weird smooth-but-tight feeling — the kind where you know it’s working but your skin is pissed. No peeling though. That’s the fermentation magic or whatever.
Fine lines around my eyes? Still there, but less angry. The weird texture on my chin? Gone by week 3. Pores didn’t shrink — they never do. But my skin looked less like a used paper towel after a night of drinking.
Use it at night, don’t be an idiot, and accept that retinal works slower than you want but faster than retinol. It’s a solid middle ground for people who can’t handle the big guns.