A fake tan gives your skin the kind of golden, sun-kissed glow that usually only comes after days of lying in the sun (or worse, on a sunbed). Modern fake tans [1] give such gorgeous, long-lasting results, you'd be forgiven for thinking you won't get a real tan underneath.

But that's not true. A fake tan doesn't protect or create any form of barrier on the skin. Though it looks like a tan, it's not the same: in almost all fake tans, the colour is the result of a reaction between an ingredient called dihydroxyacetone (DHA) and amino acids in cells on the top layers of your skin. A real tan comes from exposing your skin to UV rays from the sun; this causes melanin (your skin pigment) to rise to the surface and spread out to try to protect it.

If you get a spray tan or use a fake tan before going on holiday, you can still tan (and burn) under it. You'll still need to wear (and frequently reapply) a good broad-spectrum sun protection product [2].

A fake tan looks great and may give you a confidence boost during the first few days of a holiday, but it could also stop you from noticing the red or pink colour that comes with a sunburn. You can burn quite badly under a fake tan and not notice until it's too late. Don't let that fake glow fool you into thinking you need a lower factor: your skin isn't tanned, it's fake tanned. The clue is in the name! Always use SPF 30 or above when you're out in the sun [3].

If you're worried about what all those sun creams will do to your fake tan, opt for oil-free formulas that won't break down the colour so quickly. There are some fake tan products out there that contain an SPF [4], but if you plan to sunbathe, they're no good as you'll need to keep reapplying every few hours and could end up with a fake tan that's far too dark. Save these for home, and choose a regular sunscreen, or maybe a gradual tanner with a built-in SPF like St. Moriz Gradual Tan With SPF Protection [5] (£10). This will add a little artificial glow but allow you to build up your own tan, too, and you'll have less risk of overdoing it.