One in six school children is classified as overweight or obese however levels have stabilised in recent years, especially in girls.
That is according to a new national nutrition survey of primary school children in Ireland.
The study was carried out by a team of researchers from University College Cork, Cork Institute of Technology, University College Dublin and Technological University Dublin.
It found that the majority of children in Ireland, 78%, are within the normal weight range.
16% of children are overweight or obese, down from 25% in the last survey.
It also found that obesity levels have stabilised especially in girls going from 30% in the last survey to 19%.
Intakes of fruit and vegetables are low with children are eating about three servings a day, well below the recommended five to seven-a-day.
The survey also found that 69% of children met the recommendation of at least 60 minutes per day of physical activity.