By Dr. Tim Sandle
DIGITAL JOURNAL
May 2, 2025
Strong sales of the Topo Chico seltzer brand helped lift Coca-Cola to better than expected profits - Copyright GETTY IMAGES NORTH AMERICA/AFP/File Bryan Steffy
In 2021, the average U.S. resident bought 37 gallons of sugar-sweetened beverages. Collectively, people in the country consume about 145,000 calories per day from these drinks.
That level of consumption and its link to chronic diet-related diseases such as diabetes has become a major public health focus. Scientists at the Fralin Biomedical Research Institute at VTC have created a first-of-its-kind online marketplace to test how government policies might reduce sugar-sweetened beverage consumption.
One way to entice consumers away from something unhealthy is ‘nudge theory’. Nudge theory is a concept in behavioural science that suggests reinforcement and indirect suggestions can influence the motives, incentives, and decision-making of individuals and groups.
An alternative to the positive reinforcement associated with nudge theory is negative reinforcement, such as a so-called ‘sugar tax’. Taxes can help to ‘encourage’ consumers away from unhealthy products but his does not reveal the significance of such an outcome. A tax can reduce consumption of these beverages, but where does that consumption go? Are consumers switching to a healthier pattern of consumption, or purchasing fewer beverages entirely, or substituting a different product altogether, such as a high-sugar cereal?
A proof-of-concept study describes the Experimental Beverage Marketplace in a recent article in the journal Appetite titled “The Experimental Beverage Marketplace: Feasibility and preliminary validation of a tool to experimentally study sugar-sweetened beverage taxes and beverage purchasing”.
“This tool provides a great opportunity to systematically test the potential effects of these tax proposals on purchasing and consumption,” said Assistant Professor Jeff Stein in a statement. “It’s an important way to provide a base of evidence to inform taxes or other food policy to ensure that policy is guided by evidence and likely to have the effects we anticipate.”
For the study, the researchers tested the marketplace with 73 participants recruited online. Participants qualified for the study if they regularly bought sugar-sweetened drinks, were not on a diet, and were their household’s primary grocery shopper.
With a tax applied, participants purchased significantly less of sugar-sweetened drinks as measured by fluid ounces, number of items, and calories.
Previous researchers have developed small, brick-and-mortar experimental stores for similar studies, but those are costly and cannot adequately replicate the scale of a typical grocery store. The virtual marketplace approach makes it easier to have a wide selection of products and to conduct studies with large sample sizes.
The researchers designed the online beverage market to include hundreds of beverage options, from single servings to large multipacks, in a familiar online shopping interface. It builds on the Experimental Tobacco Marketplace, also developed at the Fralin Biomedical Research Institute.
Several U.S. localities — including Philadelphia and Boulder, Colorado — already tax sugar-sweetened beverages, but tax rates and which products are taxed vary.
It is hoped the online marketplace will help governments test proposed policies to assess their likely impacts — and identify potential unintended effects.
