An eastern suburbs couple have avoided jail after feeding their toddler a vegan diet that caused her to become so malnourished she didn't have any teeth.

NSW District Court judge Sarah Huggett sentenced both of the parents, who also didn't vaccinate the now-three-year-old, to 18-month intensive corrections orders, saying full-time custody would deprive their three children of an "important bond".

"The reckless failure of these offenders to provide their daughter with the necessities of life in fact caused serious harm," Judge Huggett said during her sentencing remarks at the Downing Centre on Thursday.

The father, 35, and the mother, 33, who lived in Queens Park when they were arrested in April 2018, cried throughout the sentencing before embracing one another at the end.