Children aged between one and three should have "nutritional checks" alongside their development milestone checks, dietitians have urged.
And they urged that focus needs to be placed on improving the nutritional status of pregnant mothers, as well as increasing rates and duration of breastfeeding.
The Irish Nutrition and Dietetic Institute (INDI), which is the representative body for dietitians and clinical nutritionists in Ireland, said that an estimated 300,000 -- one in four -- children are now overweight or obese.
It said that 19pc of all three-year-olds are overweight, with 6pc already considered to be obese.
In its submission, it said that the HSE and the Department of Health need to extend current public health programmes aimed at obesity prevention.
The body said that "opportunities exist for improvements in the identification of children at high risk of obesity and related health issues, and for better and more effective community based interventions."
It said that dietitians and clinical nutritionists have a key role in the education of parents and their children about healthy eating and strategies to improve dietary habits.
In its pre-Budget submission, the INDI recommended that the Government address "as a matter of urgency, the lack of primary care dietetic services for children with serious feeding issues or special dietary needs across the country."
And it said that education on good nutritional care should be made a requirement for all primary care team members.
The submission referred to service "black spots" throughout the country where primary care teams, and the populations they serve have no access to specialist dietetic services.
The submission called for greater commitment from the Department of Health and HSE to the nutritional care of children with nutritional problems, elderly patients and those with chronic illnesses throughout the healthcare system.
The pre-Budget submission also calls for Government commitment to eliminating avoidable malnutrition in elderly and chronically ill patients in hospital and community settings.
Malnutrition affects an estimated 140,000 patients, over half of whom are elderly. Treating malnourished patients costs the HSE an estimated €1.4bn per annum, over 10pc of the total healthcare budget, it said.