Complaints about a poster which claimed feeding meat to youngsters amounted to child abuse have been rejected by the Advertising Standards Authority.
The poster attracted 67 complaints from the public and organisations
The advertisement by animal rights charity Peta demonstrated the group's "fervent beliefs", the watchdog said.
The National Farmers' Union and members of the public were among the objectors.
It was claimed the campaign trivialised child abuse or was irresponsible because it could result in parents removing nutrients from a child's diet.
The poster, which attracted 67 complaints, features a photograph of an overweight child eating a burger above the text "Feeding kids meat is child abuse. Fight the fat - Go Veg".
Peta argued definitions of child abuse vary and are not limited to physical violence.
It believed it was acceptable to say giving youngsters food that some scientific research stated was more harmful than a vegetarian diet was "tantamount to abuse".
Peta said millions of healthy vegetarians were proof such a diet provided all the necessary nutrients.
The ASA ruled the advert carried an "anti-meat message" but parents were likely to accept nutrients should be substituted if meat was taken out of a child's diet.
Some viewers might feel the poster's text inappropriate but it understood Peta's intention.
Peta welcomed the decision.
"We're very pleased the ASA agrees that we may express our view that feeding kids meat is child abuse," campaign co-ordinator Anita Singh said.
"Even though the truth about breaking harmful eating habits may be hard to swallow, people have a right to hear it."