The singer-turned-designer laughed off comments from an interviewer about her weight as she discussed her new fashion line.
CNN reporter Alina Cho said friends were fascinated to learn she was set to quiz the former Spice Girl.
She told Beckham: 'They all say, 'Oh, what does she look like? Isn't she so thin? Does she look like she eats'?'
Victoria, 36, who has faced criticism in the past for being too skinny, said: 'Oh please tell them, yes.
'Just tell them, yes, [she's] very thin, ridiculously thin.'
She also told how she has enough money now not to have to work every day.
The mum-of-three sons, pregnant with her fourth child, said: 'I don't have to work but I'm really happy doing this [designing], making women look and feel beautiful.
'That's what I want to do.'
She told the network's American Morning show: 'That's what it's about.'