Actress January Jones of the TV drama "Mad Men" arrives at the 19th annual Screen Actors Guild Awards in Los Angeles, California on January 27, 2013.

London - Her icy blonde look as Betty Draper in the hit TV series Mad Men has won her millions of fans.

But January Jones has revealed that she is paying a heavy price for constantly changing her hair colour during her career. The 35-year-old actress says her locks are falling out in clumps after she used dye too often.

Miss Jones, who has previously been a brunette and a redhead, admits she has so many bald patches that she plans to shave her head.

‘I have been every colour and now my hair is falling out in clumps,’ she said in an interview at the Sundance Film Festival in America to promote her latest film, Sweetwater.

Miss Jones, a natural blonde, admits she enjoys changing her look.

‘I like it all colours, it makes you feel different according to what colour it is, but I prefer to be blonde,’ said the actress, who has a 16-month-old son Xander Dane. ‘My son recognises me in photos when I’m blonde.

‘I’ve been blonde, red with extensions for this film, then blonde, then black and now blonde again.

‘I’m going to have to shave it off and wear a wig.’

Miss Jones appears in the latest series of Mad Men, which airs in the US in April. - Daily Mail