Adams, a champion shot putter, shared a statement on Instagram that said Wallace needed to be educated on the human body and realise the amount of damage she was doing by making comments like that on national television.
"So size 12 is normal but size 18 is not [punch emoji]. Uppercut yourself because what your saying is disgusting."
She then wrote that many many young girls have body image issues already.
"I am a size 18-20 depending on what it is therefore I should tape over my mouth????"
Wallace responded to the criticism by Instagram post. In the caption she said she was "happy to upper cut" herself if that helped.
"Dame Valerie Adams is a great NZ'er who has devoted her life to nutrition, exercise and self motivation. As a social commentator I was asked my opinion about our appalling stats on obesity and I gave it," she said.
"I am not a dietician, personal trainer, nutritionist or medical professional, nor do I profess to be. I could have lied and said that they were just something we have to live with in the 21st century or I could say how I really felt."
She wrote that she chose to do the latter and since then had received many "wonderful and inspiring" messages from people who decided to begin a weight-loss journey in order to live longer.
"They all said it was the best thing they'd ever done and wished they'd done it sooner. One woman had lost an incredible 43kg's."
When the comments were first made AM host Melissa Chan-Green told Wallace that she can't look at somebody in a window who's modelling a fashion brand who is a size 16 and say that they're unhealthy.
"That doesn't mean that they're unhealthy," Chan-Green said
Wallace said they need to advertise people with "normal bodies", in her view a size 12, because if they advertised someone who was a size 18 people would think "that's normal and it's healthy".
Fellow host Ryan Bridge also interjected and said some people had health issues that meant they couldn't help being overweight.
"You can't paint everyone with the same brush," he told her.
Throughout the interview Wallace claimed being overweight was not healthy, however near the end of the chat she said they needed to "blame" Jane Fonda too for an increase in knee surgeries.
She said her friends had been "jumping up and down" and doing squats, likely in reference to Fonda's past life as a fitness guru, and now "so many" of her friends were having joint issues.
She did not reference whether those issues her friends were facing were weight-related.
