United States researchers estimate an 18% tax on pizza and soft drinks could push down the calorie intake of adult Americans enough to lower their average weight by 2kg a year.
The researchers, writing in the journal Archives of Internal Medicine, suggested taxing could be used as a weapon in the fight against obesity, which costs the United States an estimated $US147 billion a year in health costs.
The research team analysed the diets and health of 5,115 young adults aged age 18 to 30 from 1985 to 2006, and compared data on food prices during the same time.
Over a 20-year period, a 10% increase in cost was linked with a 7% decrease in the amount of calories consumed from soft drinks and a 12% decrease in calories consumed from pizza.
The team estimates that an 18% tax on these foods could cut daily intake by 56 calories per person, resulting in a weight loss of 2kg per person per year.
Two-thirds of Americans are deemed to be either overweight or obese.
California and Philadelphia have already introduced legislation to tax soft drinks to try to limit consumption.