Plain-language explanations of every active you'll see in our rituals. All ingredients in our formulas are natural and certified organic, with the Credo Beauty Dirty List as the floor — never the ceiling.
Hyaluronic Acid
All phases
What it does
A humectant that holds up to 1000× its weight in water; plumps and rehydrates the upper skin layers.
When to use
Every day, on damp skin, before your moisturizer. Universally well-tolerated.
When to skip
Dry climates without sealing — without a cream on top it can pull moisture out of the skin instead of in.
Ceramides
MenstrualPerimenopauseMenopausePostmenopause
What it does
Lipids your skin already makes — they cement the outer barrier so water stays in and irritants stay out.
When to use
Anytime the barrier feels tight, red, or reactive. Especially valuable in menstrual, peri, and meno phases.
When to skip
Never. They're foundational at every age.
Niacinamide (Vitamin B3)
LutealPerimenopauseMenopause
What it does
Calms redness, refines pores, regulates sebum, and supports the barrier — the most well-rounded active in skincare.
When to use
AM or PM, layered with anything. 5% is enough.
When to skip
Mixing with high-strength vitamin C — they're fine but neither is at its best.
Vitamin C (L-Ascorbic Acid)
FollicularOvulationMenopausePostmenopause
What it does
Brightens pigment, neutralizes UV free radicals, and is a co-factor for collagen synthesis.
When to use
Morning, under SPF. The pair has documented synergy.
When to skip
Same routine as strong acids or retinol — split them between AM and PM.
Bakuchiol
PerimenopauseMenopause
What it does
A plant-derived retinol mimetic — boosts turnover and firmness without the retinoid receptor irritation.
When to use
Evening, when retinol is too harsh or skin is in a reactive phase.
When to skip
If you tolerate retinol well, retinol still wins on collagen evidence.
Retinol / Retinaldehyde
MenopausePostmenopause
What it does
Increases cell turnover, builds collagen, fades pigment. The gold standard for visible aging.
When to use
2–3 nights/week, building up. Always pair with SPF the next morning.
When to skip
Menstrual phase, broken skin, pregnancy, or when starting any new active.
Peptides
FollicularPerimenopauseMenopausePostmenopause
What it does
Short amino-acid chains that signal the skin to produce more collagen, elastin, or filaggrin.
When to use
Layered serums in AM or PM. Gentle enough to combine with almost anything.
When to skip
Nothing — peptides play well with the whole cabinet.
Salicylic Acid (BHA)
LutealPerimenopause
What it does
Oil-soluble exfoliant that gets inside the pore to clear congestion. The right tool for hormonal breakouts.
When to use
2–3× per week in the luteal phase, on T-zone or affected areas.
When to skip
Daily use, full-face, or stacked with retinol the same night.
Lactic / Mandelic Acid (AHA)
FollicularPostmenopause
What it does
Surface exfoliants that smooth texture and even tone. Mandelic is gentler than glycolic for sensitive skin.
When to use
Follicular phase, 1–2 evenings a week.
When to skip
When using retinol the same week, or during menstrual/peri flares.
Phytoestrogens (Red Clover, Soy Isoflavones)
PerimenopauseMenopausePostmenopause
What it does
Plant compounds that mildly bind skin's estrogen receptors — topical support when systemic estrogen is low.
When to use
Daily essences or serums in peri and post.
When to skip
If pregnant or on hormone-sensitive medication, check with your physician first.
Mineral SPF (Zinc Oxide, Titanium Dioxide)
All phases
What it does
Reflects UV physically instead of absorbing it. Less photosensitivity, friendlier to reactive skin.
When to use
Every single morning. SPF 30+ minimum; SPF 50 once skin is thinning.
When to skip
Never.
Squalane
All phases
What it does
A lightweight emollient — mimics the skin's own sebum so it absorbs without clogging.
When to use
PM, layered into a cream or as the last step on dry skin.
When to skip
Choose plant-derived squalane (sugarcane or olive). Shark-derived versions are still on the market — avoid.