Researchers at Monash University have shown that a GST on fresh food will have a significant impact on population health, especially in relation to obesity.

Dr Claire Palermo, Department of Nutrition and Dietetics, modelled the cost of a GST on fresh food and the impact it will have on the price of the Victorian Healthy Food Basket (VHFB).

Developed by Dr Palermo in 2007, the VHFB monitors the cost and accessibility of healthy food for four family types.

"The price of food influences what we purchase and consume," Dr Palermo said.

"The average cost of food in Victoria has increased marginally over the last three years."

In 2012 it cost an average of $424 per fortnight to meet the nutritional requirements for a family of four - two adults and two children. The cost of this same healthy food basket increased to $447 in 2014.

"Our latest data suggests that the average VHFB will increase by $45 per fortnight for a family of four if a GST on fresh food is introduced," Dr Palermo said.

"Of particular concern, our evidence suggests healthier foods may be replaced with cheaper alternatives that are energy dense and nutrient poor."