"I would never make a comment like that. I think it's way too personal," Naomi told radio show Sway in the Morning.
"I don't know what Ashley eats and that's not necessarily because you're bigger than me, you're eating tons of food. I've got tons of friends who are bigger."
The supermodel added: "It could be a hormone problem. I don't think Ashley's big like that. She's not a beast. I think sometimes our bones are bigger and we're just built that way. That doesn't mean we're fat.
"I wouldn't comment on someone's size. I just think it's wrong. I think she's a beautiful woman, regardless what colour or creed. She should be able to model." Naomi's comment come after former model Cheryl insinuated that Ashley was 'unhealthy', criticising Sports Illustrated for choosing Ashley for one of the three covers of its 2016 Swimsuit issue, insisting it was promoting an unhealthy body type.
Attending a pre-Oscar party, Cheryl told E! News: "I don't like that we are talking about full-figured women because it's glamorising them, and your waist should be smaller than 35 [inches]. That is what Dr. Oz said and I am sticking to it."
She continued: "No, I don't think it's healthy. Her face is beautiful, but I don't think it is healthy in the long run."
Cheryl's comments sparked outrage on Twitter. So much so that Cheryl took to the social media channel to defend herself.
"Being anorexic/bulimic/overweight all connected to health problems. I want all to be as healthy as they can," she wrote.
However, the tweet led to even more outrage, with many saying she was comparing Ashley's curvaceous figure to an eating disorder.
Cheryl deleted the tweet and simply wrote: "My sincere apologies to everyone I have hurt. I truly just want everyone to be healthy & happy."