New "me-sized plates" have been launched by the authority to help parents recognise just how much their children should be eating.
All reception children in Lincolnshire have received a me size plate at school.
Lynne McNiven, from NHS Lincolnshire said: "The majority of feedback we had from parents was supportive and many parents admitted they were giving their four year old child bigger portion sizes than they should.
"Children who are given their own plate are more likely to take an interest in their food and what they eat, but portion size is only one part of the jigsaw we need to complete to make sure our children grow up fit and healthy."
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