Skincare Generics

Who should use peptides in their skincare routine?

Peptides benefit anyone concerned with early signs of aging, loss of firmness, or skin barrier integrity. They are particularly valuable for those in their 30s and beyond who want to support collagen levels. Because they are generally non-irritating, peptides are also a great option for sensitive skin that cannot tolerate retinol or acids. They work best in a leave-on serum or moisturizer, not a rinse-off product.

In what order should I apply skincare products?

The general rule is to apply products from thinnest to thickest consistency. A standard morning routine goes: cleanser, toner or essence, serums, eye cream, moisturizer, then SPF. At night, after cleansing, apply serums like retinol or acids, followed by a richer moisturizer or facial oil on top. This order maximizes absorption of active ingredients before heavier products seal them in.

What skincare ingredients should not be mixed?

The most important combinations to avoid are retinol with AHA/BHA acids (increases irritation), vitamin C with AHA/BHA acids (can cause over-exfoliation and irritation), and benzoyl peroxide with retinol (they can deactivate each other). Additionally, two strong exfoliants should not be used simultaneously. When in doubt, use one active per routine and separate conflicting actives to morning versus evening.

Does pH matter when layering skincare products?

Yes, pH is relevant for certain actives. Vitamin C (L-ascorbic acid) requires a low pH below 3.5 to be effective, and AHAs/BHAs work best at pH 3–4. Applying these after a high-pH toner or essence can reduce their efficacy. Wait one to two minutes between applying a low-pH active and a higher-pH product to allow the skin's pH to stabilize. For most moisturizers and serums at neutral pH, order by texture is sufficient.