One in six school children are overweight or obese and while levels appear to have stabilised or decreased in recent years, especially in girls, they are still too high.
Results from the latest National Children's Survey 2017-2018 show that 16% of five to 12-year-olds are obese or overweight – 19% of girls and 14% of boys.
A similar study conducted during 2003 and 2004 found that 25% of children were obese or overweight – 30% of girls and 19% of boys.
Consumption of sugar, salt and saturated fat are higher than recommended but there is a shift towards reduced-fat milk, brown bread, whole fruit and water.
Children are still not eating enough fruit and vegetables - at about three servings a day, it is well below the recommended five to seven.
The study was conducted by a team of researchers from University College Cork, Cork Institute of Technology, University College Dublin and Technological University Dublin
Dr Janette Walton from Cork Institute of Technology said the scientific data provided by the study could be used to develop healthy eating guidelines.
Dr Walton pointed out that eating at home was the main source of calories (87%) and the main influence on dietary quality for school children.
“We need to continue to promote guidelines for healthy eating for this age group – guidelines that focus on appropriate portion sizes, lower consumption of fat, salt and sugar and higher intake of vegetables and other foods that provide key vitamins and minerals,” she said.
Most children are getting enough vitamins and minerals but significant numbers have inadequate intakes of vitamin D (94%) and calcium (37%).
Dr Breige McNulty from UCD's Institute of Food and Health said the high levels of overweight and obesity in school children needed to be addressed.
Almost seven out of ten (69%) children achieved the recommended 'at least 60 minutes' of physical activity per day.