London, No 22 A L'Oréal advert fronted by Cheryl Cole is at the centre of a row after viewers accused the X Factor judge of misleading them.

Cole, 26, appears in a television ad in which she sings the praises of L'Oréal Elvive Full Restore 5, a shampoo and conditioner range.

Thirteen viewers have complained to the Advertising Standards Authority about the commercial because Cole wears hair extensions.

The authority, however, rejected the claims as a message is shown during the advert, which says that Cole's hair is "styled with some natural extensions".

"A problem would only arise if the ad did not make clear that she is wearing these extensions. It is also worth noting that the hair extensions are made from natural hair and have been treated with the products being advertised," Times Online quoted the watchdog as saying.

However, Cole's hairdresser Julien Guyonnet has reportedly revealed that she uses artificial fibre extensions because the glue used for natural ones was damaging her hair.

He said: "She is very nice and down-to-earth. She didn't tell me she was doing the adverts. She used to use human hair but the glue damaged her hair. Of course, she may have used human hair for a photoshoot depending on the hairdresser on the shoot and what company it was for."

A L'Oréal spokesperson said she did not know whether Cole used artificial extensions, but added: "Cheryl has worn hair extensions for some time. They are part of her look and are cared for in the same way as normal hair."

Meanwhile, Cole's representative said: "L'Oréal are within their rights and the ads are not breaking any rules. We would never comment on what type of hair extensions Cheryl is using because these are quite personal questions." (ANI)