And model Abbey Clancy has revealed she also struggles to keep them. The mum-of-two said every January she tries to quit alcohol, but fails.
"I try to do no alcohol. But I've got no will power so I don't make them. I never stick to my New Year's Resolutions," Abbey told Reveal.
The mum-of-two, who is the new judge on the upcoming series of Britain's Next Top Model – the show which helped launch her career nine years ago - also spoke about supermodels who inspired her to chase her dream of becoming a model.
"I loved all the nineties supermodels and Victoria Secret back in the day," she explained, adding that the model of the moment for her is Kendall Jenner.
And what does the star, who turns 30 on January 10, have to say about Victoria Beckham's models coming under fire for being skinny last autumn?
"A lot of these girls are 6ft tall - they have long arms, it's a body type, they're naturally thin. With Britain's Next Top Model, we've looked for healthy, strong girls. Those girls are genetically like that."
Abbey is the new judge on Britain's Next Top model, which airs on Lifetime from 14 January.
Read our full chat with Abbey in this week's Reveal magazine - out NOW!
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