A Sydney mother who put her baby in danger of starvation by breastfeeding while on a raw food diet has been handed a 14-month suspended sentence.

The 33-year-old woman, who cannot be identified, was last year trying to treat her six-month-old son's severe eczema and sought the advice of a naturopath who allegedly first put her on the diet and later convinced her to consume only water.

The woman's son nearly died of starvation and dehydration as a result.

The Director of Public Prosecutions (DPP) lawyer, Alex Brown, told the Campbelltown Local Court that the woman "was a nurse who decided to blindly follow a naturopath she had only just met" and that her child came within days of death.

Magistrate Ian Guy said the mother would have been given jail time if she had not agreed to give evidence against the naturopath, Marilyn Bodnar, who is expected to face a committal hearing on Monday.

"On any view, [the offence is] extremely troubling and disconcerting considering how long the child had been vomiting," he said.

Bodnar has not entered a formal plea, but has indicated she will plead not guilty to charges of recklessly causing grievous bodily harm and failing to provide for a child causing danger or death.

Police claim the 59-year-old, from Leppington, gave advice to the mother, over the treatment of her son's eczema in February 2015.

Officers allege the naturopath advised the mother to stop medicating her child.

In May 2015, the baby boy was admitted to hospital with severe malnourishment and developmental issues.

After previous court appearances Bodnar declined to comment, but her lawyer Rick Mitry said she would strenuously defend herself against the charges.

Bodnar has remained on bail since her arrest on the condition that she not provide naturopathy services to anyone under the age of 16.