A food addict tells her own story.

Natasha was a highly qualified manager in a large company when a co-worker pointed across the room to a tall, svelte woman and said: "See her? She's a good manager."

Natasha replied, "But she's not half as good as I am!"

The reply was, "You're right, but she looks like a manager."

"When you hear comments like that you just feel like giving up. What's the point?" she says.

Natasha was never a fat child. Her weight problems started in her 20s and, under medical supervision, she tried numerous diets. She was prescribed amphetamines, anti-depressants (which supress appetite), then a drug that prevents fat being absorbed from food and, at one time, a liquid diet of nutrition shakes. She bought gym equipment, got a personal trainer, consulted nutritionists and had long-term psychotherapy.

Yet Natasha still found herself fighting a losing battle, particularly after her children were born. She continued to experience prejudice from people who judged her purely on her size.

"When you're fat, people think you're stupid and are surprised to hear intelligent sentences come out of your mouth," she says. She became terrified of eating in public, and was increasingly secretive and ashamed about her eating.

She was willing to starve herself to the point of weakness to "be thin". She got wrapped up, she says, in "the utter insanity of eating to excess, controlling food to excess and obsessional thinking about food".

The yo-yo dieting only made her situation worse. By her early 40s, Natasha had become "morbidly" obese.

"My doctor told me that I was slowly committing suicide," she says. She entered an addiction treatment centre, where she was encouraged to strip away the addict from her personality, so that the real Natasha could emerge.

"The truth is that it is not the weight that makes you unhappy, it is your addictive behaviour and your inability to cope with emotional events or to feel in control of your life without eating or dieting to excess," she says.

In the treatment centre programme, she was introduced to Overeaters Anonymous, a 12-step programme, where members share their support, insights and hope, as well as focusing on spiritual development.

The memoir, Fat Girl, gives the impression that there is no hope for women with food problems. Natasha disagrees: "As someone who but recently had come to believe that there was no hope to break the cycle of 20 years of eating and dieting - which had driven my weight to life-threatening proportions, myself to depression and my husband to despair - I could identify with her pain and anger only too well. I too had talked to numerous therapists to no avail. Therefore, I found her lack of hope more painful for having found hope myself, together with a way forward through an addiction centre and Overeaters Anonymous."

Natasha, who has lost more than four stone in the past six months, eating full, satisfying meals, feels she has been given "a new lease of life that is more valuable than all the tempting food out there. When I feel like bingeing or overeating now, I have tools which I can use to help.

"I am not cured. I will never be cured. Like an alcoholic, I will always be vulnerable to my addiction, which is cunning, baffling and powerful. But unlike an alcoholic, I cannot avoid the substance," she adds. "I have to eat. So it's imperative to find a new relationship with food."

• Name is changed in accordance with Overeaters Anonymous's policy of confidentiality.

• For further information: www.overeatersanonymous.org