says "drink and drugs are an allergy" for her.
The supermodel has admitted she experimented with cocaine when she was in her 20s and had made it in the fashion
industry, and has admitted the illegal drug had a negative impact on her life.
Discussing her problems with substance abuse, she said in an interview with the UK edition of GQ magazine: "It rips you world apart. I never thought I was an alcoholic but it goes hand in hand with the drugs. Emotionally I was just gone. I was emotionally unattached to myself. You just want to numb your pain. And I've got tons of stuff. Same as everybody else. I didn't like the way I was. Drink and drugs are an allergy for me, and they don't make me a better person."
Naomi - whose mother Valerie raised her as a single parent from the age of 18 after her father walked out on them both when the catwalk legend was just two months old - took cocaine when she was out partying and didn't initially realise the damage it could cause.
She explained: "I was a party girl. I started quite late, 24. I was having fun. It wasn't that I couldn't get out of bed in the morning without it. It wasn't a coping mechanism. It was a party thing and I didn't realise how powerful it was, in a very wrong way. The fun comes with consequences, you are killing yourself...I was an active addict. But I could still function."
The 40-year-old model was proud of herself when she stopped using cocaine and insists there is no shame in seeking help.
She said: "Recovery is a positive thing. There's nothing to be ashamed of. When you know you need help, and seek help, you need that time to deal with it. Get used to that new discipline. Tell when you are ready to tell. There's no shame. There are people who get out of that prison, like Eric Clapton. I wanted to know what it was - that peace, that serenity. A lot of my friends didn't want to hang out with me when I came back. That hurt."
The March issue of GQ is available on newsstands in the UK from Thursday 3 February.