Retinal is retinaldehyde — the immediate precursor to retinoic acid, which means the skin performs a single conversion step instead of two (as with retinol). The result is meaningfully faster visible smoothing of fine lines with a gentler sensation profile.
Comparative studies suggest retinaldehyde acts up to eleven times faster than retinol while remaining well tolerated; Coyglow's Night Shift Retinal Serum micro-doses it alongside squalane.
How to use: Evenings only. Start twice weekly, build to nightly. Always pair with a morning SPF — vitamin A derivatives photosensitize by convention.
Cautions: Avoid during pregnancy and breastfeeding; expect a mild adjustment period.