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Gel polish

Gel polish is a coloured coating that does not dry in air but hardens under a UV or LED lamp in seconds. It goes onto the natural nail in thin layers and comes off through a specific removal routine rather than with ordinary nail polish remover.

What is actually in it?

A liquid resin carrying pigment and a set of molecules called photoinitiators. In the bottle nothing happens: the resin stays fluid. When light of the right wavelength hits it, the photoinitiators start a chain reaction that links the resin molecules to one another and the layer turns from liquid to solid. That is curing. It is not drying: in traditional polish a solvent evaporates and leaves a film behind, whereas here the chemistry of the product itself changes.

Why three layers?

Each one has a job. The base grips the nail and cushions the rest; it is the layer that decides whether the whole thing stays put or lifts. Colour carries pigment and goes on thin, usually in two passes, because a thick coat cures on the outside and stays soft underneath. Top seals the stack, delivers the gloss or the matte finish, and takes the daily wear. Skipping any of the three saves almost no time and costs real wear.

How long does it genuinely last?

Two to four weeks looking good on fingernails. The limit is rarely the product wearing out; it is nail growth pushing the coating outwards until a visible band opens at the base. On toes it lasts considerably longer, four to six weeks, because the nail advances more slowly. Frequent manual work, hot water and household cleaning products all shorten the window.

How is it different from builder gel?

The confusion is common because both cure under light. Gel polish is a colour layer a few tenths of a millimetre thick: it follows the shape of the nail and does not change it. Builder gel is a denser material used to add thickness, level a surface or extend the free edge. The two are often combined, and putting gel polish colour over a builder base is routine.

How does it come off?

Never by peeling. The usual method is to file off the top layer to break the seal, then soften the product with acetone, wrapped in foil or held with clips, for 10 to 15 minutes. The alternative is to take almost all of it off with an e-file, leaving a minimal film behind. What must not happen is pulling at an edge that has lifted: what comes away with it are layers of the nail itself.

What are the most common mistakes?

Flooding the skin with base is the first: product sitting on skin rather than nail lifts within days and opens a route for moisture. The second is a thick colour coat, cured on the surface and soft underneath. The third is failing to cap the free edge, the thin pass along the very end of the nail that closes the stack. The fourth is using a lamp that does not match the product, since each range is formulated for a particular wavelength band.

Why does upkeep matter?

Because polish is a finish with a date on it, not something applied and forgotten. Within its window, 2 to 4 weeks on fingernails, it wants renewing or removing. Past that point the edge starts to lift and the stack stops doing the job it was put there to do.

Wearing polish that has lifted or cracked is the thing to avoid, and the reason is mechanical: a gap opens between the loose layer and the nail, water and dirt get into it, and that gap neither dries nor cleans itself. There is a second, equally practical reason: while the nail is covered, nobody can see how it is doing.

Removal is always done properly, in the salon or at home by the correct method. Never by peeling: whatever lifts when an edge is pulled takes layers of the nail with it.

Sources: Regulation (EC) 1223/2009 on cosmetic products (EUR-Lex) · AEMPS · Cosmetic products (Spanish Medicines Agency) · Scientific Committee on Consumer Safety (SCCS), European Commission

Published: 12 October 2026 · Last reviewed: 12 October 2026