A lack of key nutrients in preschoolers' diets may increase their chance of developing heart problems and chronic diseases in later life, according to research published in the Medical Journal of Australia today.
Shao Zhou and Maria Makrides from the Women's and Children's Health Research Institute in Adelaide found children were not getting enough fibre or omega-3 fatty acids in their diets and were eating too much saturated fat.
"Australian children aged one to five years old are following a dietary pattern that may be associated with adverse long-term cardiovascular health and chronic disease," they wrote.
Curtin University School of Public Health dietitian Christina Pollard said the study proved preschoolers ate too many biscuits, cakes and sweet cereals and drank too much full-fat milk.
She said this could lead to high cholesterol, high blood pressure, type 2 diabetes and heart disease.
There was evidence children were developing these problems, usually seen in adults, earlier in life because of poor nutrition.
"Adult onset diabetes now seems to be occurring as young as adolescence," she said.
"This paper is good at highlighting that if you don't have a nutritious diet - and by that I mean lean meats, wholegrain products, fish, fruit, vegies and low-fat milk - as well as staying physically active, you are going to suffer the consequences of that earlier and that can lead to lifelong health issues."
Clinical Professor Trevor Parry, from the University of WA's School of Paediatrics and Child Health, said busier lifestyles led to children eating less fresh produce and more takeaway food, which had more saturated fat, carbohydrates and energy.
Professor Parry said reducing the amount of time children watched TV or played video games was as important as good nutrition.
He said obesity was linked to changing patterns of exercise as well as nutrition.
Mt Pleasant mum Denise Martin said she taught her children Zac, 4, and Will, 2, good dietary habits to reduce the risk of health problems.
"I want them to grow up to be fit, healthy, strong boys," she said.