Sunscreen: the only guide you need
The best sunscreen is the one you will actually put on every morning. Everything else is detail.
Why this is the one step to get right
Sunscreen prevents more visible ageing than every anti-ageing product combined, and it is the single most important intervention for pigmentation of any kind. If you are treating dark spots or melasma without daily sun protection, you are refilling a bucket with a hole in it.
How much
Two milligrams per square centimetre is the amount tested to give the SPF on the label. In practice:
- Face: about a third of a teaspoon, or two fingers' length squeezed onto your index and middle fingers
- Face and neck: half a teaspoon
Most people apply between a quarter and half of this, which means a labelled SPF 50 is performing somewhere closer to SPF 15. Under-application is by far the most common mistake.
Mineral or chemical?
Mineral filters — zinc oxide, titanium dioxide — sit on the surface. They rarely irritate, which makes them the sensible default for sensitive, rosacea-prone, or post-procedure skin. The trade-off is a white cast, particularly on deeper skin tones.
Chemical filters absorb UV and convert it to heat. They are cosmetically far more elegant, which for most people is the difference between wearing sunscreen and not wearing it.
Neither category is safer or more effective in general. Pick on how it feels, because that determines whether you use it.
Reapplication, honestly
The guidance is every two hours outdoors. Indoors, away from windows, one morning application is broadly fine — UVA does come through glass, but the exposure sitting in an interior office is low.
If you are outside, swimming, or sweating, reapply properly. Powders and mists are for topping up over makeup, not for a first application.
What the numbers mean
SPF 30 blocks about 97% of UVB. SPF 50 blocks about 98%. The gap looks trivial written that way, but it is a third less UVB getting through — worth having if you burn easily or are treating pigmentation.
"Broad spectrum" means it covers UVA as well as UVB. UVA is the wavelength most associated with ageing and pigment. Look for the phrase, or a PA rating of PA+++ or higher.
Common complaints, solved
- White cast: switch to a chemical or hybrid filter, or a tinted mineral one
- Greasy: look for gel or fluid textures rather than creams
- Pilling: you are layering over a product that has not absorbed — wait longer, or simplify what is underneath
- Stings my eyes: usually chemical filters; a zinc-based stick around the eye area avoids it
- Breakouts: try a fluid sunscreen designed for acne-prone skin
Ingredients mentioned
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Want this applied to your own skin?
The quiz turns all of this into a specific routine, with the reasoning shown for every choice.
Take the quizRoutine is educational and is not medical advice. Recommendations are generated from the answers you gave and general dermatological guidance — they cannot account for your full history. For persistent or severe skin conditions, or before starting anything new during pregnancy, speak to a doctor or dermatologist.