The Barbarella star was "traumatised" after the screen legend made a disparaging remark about her body, and insists the incident contributed to a lifelong obsession with her appearance.
She tells Britain's You magazine, "I was brought up to feel fat, though my father wouldn't tell me directly - he'd get one of his wives (Fonda married five times) to tell me that I shouldn't wear a bikini. One day, I overheard him talking about me and I can't even tell you what he said because it traumatised me and I can't pretend I'll ever get over it.
"So I was the product of objectifying parents and also a product of the '50s, when the way a woman looked was so important. It's why I pay attention to my appearance now. I believed that to be loved you had to be perfect, and even though I've got over that now, it took a long time."
Fonda went on to battle bulimia and admits none of her three husbands noticed her eating disorder.
She adds, "We develop addictions because we're missing something and my addiction was food. I moved outside myself, left a big, empty space inside, and tried to fill it with food. I went through phases of bingeing and purging and it was many years before I could sit at a table without feeling any anxiety. Bulimia is very easy to hide, but you can't be intimate with people if you're an addict."