The TV star has been criticised for smoking and drinking on her MTV fly-on-the-wall documentary Kerry Katona: Crazy In Love.
She admits she's still smoking and has the odd drink - but only in moderation.
'I'm only on 3 or 4 cigarettes a day and I'm desperately trying to quit,' Kerry writes in her OK! diary.
'You saw me drink one glass of wine on Friday Night With Jonathan Ross and that was because I was nervous. Then I had 2 glasses of champagne on New Year's Eve which I'm entitled to.'
The former Atomic Kitten says she has proof to counter allegations she snorted a line of cocaine when 4-months pregnant.
'I've got proven drug tests to show I was clean,' she says.
Kerry, 27, is due to give birth to her fourth child in May, her second with husband Mark Croft, 37.
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