The mum-of-five, who was eating Christmas cake with cheese during a link between the This Morning and Loose Women studios, told Holly that she should it eat too because she's 'losing far too much weight'.
While Holly let the remark go and tried not to react, viewers quickly took to social media to criticise Katie for 'body shaming' the TV presenter.
One said: 'Wow, I can't believe Katie Price just body shamed lovely Holly on #ThisMorning that's NOT okay!!'
Wow, I canâ€™t believe Katie Price just body shamed lovely Holly on #ThisMorning thatâ€™s NOT okay!!— Belle (@hkp074) December 12, 2017
A second wrote: 'Katie price telling holly she's loosing too much weight? Uncalled for #ThisMorning'.
A third commented: 'Ummm what on earth was that dig at Holly's weight from Katie Price just then??? she always looks gorgeous and that was so uncalled for #ThisMorning'.
Some even said they thought Holly looked upset after the 'dig': 'Holly actually looked quite upset then after that snide comment from Katie price about her weightloss 😱 wind your neck in Katie she looks fantastic and healthy #ThisMorning'.
Holly actually looked quite upset then after that snide comment from Katie price about her weightloss ðŸ˜± wind your neck in Katie she looks fantastic and healthy #ThisMorning— Linda (@LloveForLifee) December 12, 2017
Later on in the show, Katie had to be led off by fellow Loose Women panellist Ruth Langsford after breaking down in tears over her mum's illness.
Discussing her terminally ill mum Amy following Keith Chegwin's death, who suffered from the same condition, Katie said: 'I don't want my mum to die... How can my mum die, it could be my last Christmas with her.'
After taking her backstage, Ruth explained why Katie wanted to be there: 'She wanted to come on today and talk about Keith's condition and raise awareness… Unfortunately as you saw she couldn't cope talking about her mum so she's gone off and we've got her a cup of tea and we are going to continue the show without her.'
Fans thought Holly looked 'upset' after the comment
Katie's comments about Holly's weight loss follow criticism from fans, who often comment on her weight loss on her social media posts, and say she's lost her 'enviable shape'.
When asked what the secret behind her transformation is, the mum-of-three has refused to comment, telling Prima magazine: 'I don't want to encourage eating disorders. I try not to focus too much on my appearance.
'As long as I'm being healthy, that's good enough for me. I'm quite active and I try not to let the way I look be the main focus because it's not the important thing.'