How long before exfoliating shows?

Roughly two weeks for surface brightness and closer to eight for tone. If nothing has changed at all after a month, the problem is more likely dehydration or sun than turnover.

Can I use vitamin C and an exfoliant together?

On alternate days, comfortably. Layered in the same routine they can sting and there is little to gain. Vitamin C in the morning and the acid at night on the nights you use it is a simple way to keep both.

Does drinking more water help?

It helps if you are actually dehydrated, and it is not the lever most articles suggest. Water applied to the skin and then sealed does more for how the surface looks than water drunk does.

The answer

My skin looks dull

Skin looks dull when the surface is uneven — dead cells sit unevenly and scatter light instead of reflecting it, so no amount of highlighter fixes what is happening underneath. Three things change it, in order of how much they do: an exfoliant that clears the surface, which is chemical rather than a scrub; sun protection, because most of what people call dullness in their thirties is accumulated sun; and vitamin C, which works on tone rather than texture. Hydration matters too but it is a same-day effect. Exfoliation is the one that shows in a fortnight.

What answers it

Paula's ChoiceSkin Perfecting 2% BHA liquid exfoliantA BHA works into the pore as well as across the surface, which is why it suits dullness that comes with texture and congestion rather than just flatness.Buy on Amazon
La Roche-PosayAnthelios Melt-In Milk SPF 60The unglamorous half of this. Sun is what causes most of the tone change people describe as dullness, and nothing else on the list holds if this is missing.Buy on Amazon
Paula's ChoiceC15 Super BoosterVitamin C works on tone rather than texture — the two are different complaints and this is the one for uneven colour rather than uneven surface.Buy on Amazon
L'Oreal ParisTrue Match Lumi GlotionFor today rather than for the cause. A liquid illuminator mixed into base gives back the light while the rest is doing its slower work.Buy on Amazon

Prices live on Amazon, where they change hourly — so we never quote one. Every product here is a brand we would name out loud.

Chemical, not physical

A scrub with grains in it removes some surface and roughs up the rest, which is why skin can look brighter for an hour and worse by evening. An acid dissolves the bonds holding dead cells on and lets them leave evenly. Start at two or three times a week — daily acid use is how people end up with a damaged barrier and a new complaint.

Dull and dehydrated look the same and are not

Dehydrated skin is flat because it has no water in the surface layer, and it responds within a day to a humectant and something to seal it. Dull skin is flat because of texture and tone, and takes weeks. If your skin looks better an hour after moisturiser, that was dehydration. If it does not change, that is the other thing.

What highlighter can and cannot do

It puts light back on the high points and it genuinely helps a photograph or an evening. What it cannot do is make an uneven surface reflect evenly, which is why a heavy shimmer on textured skin reads as texture rather than as glow. Use it as the finish on top of the slower work, not instead of it.

Questions

How long before exfoliating shows?: Roughly two weeks for surface brightness and closer to eight for tone. If nothing has changed at all after a month, the problem is more likely dehydration or sun than turnover.
Can I use vitamin C and an exfoliant together?: On alternate days, comfortably. Layered in the same routine they can sting and there is little to gain. Vitamin C in the morning and the acid at night on the nights you use it is a simple way to keep both.
Does drinking more water help?: It helps if you are actually dehydrated, and it is not the lever most articles suggest. Water applied to the skin and then sealed does more for how the surface looks than water drunk does.

Your turn

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