SKINCARE: FRIENDS AND ENEMIES

Don’t: Retinol can aggravate skin when used alone if you’re not used to it, so don’t add other stress factors to the equation. Avoid vitamin C, acids, exfoliants or layering more than a single retinol product – these power ingredients can be used in the morning, saving your retinol for night use.

Do: If you are using retinol in the day, sunscreen is non-negotiable. The sun’s rays actually decrease the efficacy of the ingredient, so team it with hyaluronic acid to hydrate and soothe skin that is adapting to retinol.

Don’t: Though they are both brighteners, vitamin C and niacinamide can react to each other. These two should either be avoided in combination or layered with at least a 10-minute gap between applications.

Do: As it’s not sensitive to the sun, vitamin C appears in many products designed for daytime use. It’s a great friend of sunscreen, heightening protection from photo damage when combined. It also teams well with Vitamin E for greater antioxidant effects.

Don’t: Like retinol, exfoliating acids take time for your skin to adjust to, so avoid aggravation by steering clear of other aggressive ingredients like retinol, vitamin C or physical scrubs. And while some products may combine AHAs and BHAs, those are lab-tested, so layering high-dose glycolic acid products on top of salicylic acid or benzoyl peroxide could also cause a reaction.

Do: Even once you are used to them, acids resurface your skin and dry it out, so go heavy on soothing and hydrating ingredients like hyaluronic acid.

Don’t: Combining oil-based and water-based products isn’t a great idea – oil will create a layer over your skin that prevents water-based products from sinking in.

Do: That said, if you know your way around an ingredient list, you can identify water-based products and use them earlier in your routine to allow for absorption. In other words, an oil-based essence and a water-based moisturiser would be a waste of product, but a water-based toner followed by an oil product is A-OK.