Wellness guru Dr Libby Weaver has made a public apology and recalled 20,000 copies of her latest book after using an offensive term.
In her book What Am I Supposed to Eat she used the term 'mongolism' when describing people with Down Syndrome.
"I used a word to describe Down Syndrome that I thought was a current medically used word," she said in a statement on Monday.
"It has since been brought to my attention it is a word that is used in a derogatory way and I am mortified to have caused anyone any distress through this error, particularly children with Down Syndrome and their families."
"Please accept my deepest apology, I am so very sorry for any hurt this has caused anyone," Dr Weaver said.
Copies of the book were being recalled from stores and those who have already bought the book would be eligible to apply for a refund.
Late last year, Dr Libby separated from her husband, Chris Weaver, who remains involved in her company.
The popular holistic nutrition specialist and wellbeing advocate is due to give seminars in New Zealand over the coming month.