What's the secret to encouraging people to eat fruit? Lower the price.
An Australian study has found that people will buy 35 per cent more fruit – or 2.4 additional servings – when the price is discounted by 20 per cent.
But the effect of discounting was more profound for fruit than vegetables and had no impact when it came to water or low-calorie drinks.
The findings from the Supermarket Healthy Eating for Life trial have been published in The American Journal of Clinical Nutrition, and will bolster the health claims of those who argue the GST should not be extended to fresh food.
Lead author Kylie Ball, of Deakin University's Centre for Physical Activity and Nutrition Research, said it was the first randomised controlled trial in Australia and one of the first in the world to examine how pricing affected food-purchasing behaviour, and had implications for public policy.
Previous research indicated that 95 per cent of Australians did not eat enough fruit and vegetables for good health, she said.
"Fiscal approaches like taxes and subsidies and moderating the GST are often advocated as solutions to poor diets or obesity in countries like Australia but up until now most of the evidence for their effectiveness has been based on modelling studies, rather than trials like this which look at people in the real world and what happens when you put in a discount," Professor Ball said.
"We would not advocate for a GST to be added to fruit and vegetable products because price does influence the purchase of these products."
Participants in the study were required to be aged between 18 and 60 and female, because of the role of women as "key nutrition gatekeepers" in their households.
One group was given a 20 per cent discount on fresh, tinned and frozen fruit and vegetables, diet or low-calorie fizzy drinks and water, which they obtained by swiping their FlyBuys card at Coles supermarkets.
Another group was sent eight newsletters with resources such as budgeting worksheets, recipes, shopping lists and family tips for healthy eating.
A third group was sent the newsletters and given the discount, while a fourth group was subject to no intervention.
After three months, price reduction alone participants purchased 35 per cent more fruit and 15 per cent more vegetables than the controls, but they were no more likely to buy low-calorie beverages or bottled water.
Those who were given a price reduction and the nutritional packs also bought more fruit and vegetables, but there was no significant difference between the control group and those who were only given the nutritional packs.
The results were spread equally among high- and low-income households.
While processed food is already subject to the GST, there have been calls for the exemption on fresh food to be reconsidered.
Extending the GST to cover fresh food would raise $6 billion per year, according to a January report by the Grattan Institute.
But health groups have warned that imposing a tax on fresh food could lead to higher rates of obesity, heart disease and cancer.
A 2010 study conducted in Western Australia found welfare recipients need to allocate half their disposable income to food, compared to 16 per cent for the average income earner.
