How much does cost matter when shoppers look for healthy foods?

A University at Buffalo pediatrics professor wants to find out.

UB Distinguished Professor Leonard H. Epstein has established a large-scale, Internet-based experimental grocery store to develop evidence-based science about how people decide what to buy.

“My ultimate goal is to advocate the use of the scientific method to set public policy,” Epstein said in a news release.

He is recruiting 800 grocery shoppers for a $1.7 million, randomized, controlled study funded by the National Institutes of Health, which runs until 2015.

To participate, shoppers must be age 19 or older and have at least one child at home between ages 2 and 18. Individuals interested in participating in the Grocer-E study should call 829-6694 or 829-6122 or visit

Participants “shop” in UB’s behavioral medicine lab, using an online grocery store that was developed by Epstein and colleagues at UB, featuring more than 11,000 items. In the experimental grocery store, prices are altered depending on a food’s nutritional value. For example, junk foods may be taxed while healthier foods may be subsidized and therefore much cheaper.

Participants have a one in 10 chance to win the groceries they selected.

The study aims to assess how shoppers’ purchasing decisions respond to changes in price and whether better nutrition information at the point of purchase will encourage shoppers to change purchasing behaviors.

“Nobody has looked at this in an experimental way,” said Epstein, chief of the Division of Behavioral Medicine in the Department of Pediatrics in the UB School of Medicine and Biomedical Sciences and a faculty member in the Department of Social and Preventive Medicine in the UB School of Public Health and Health Professions.

“There’s so much talk about taxing sodas and junk food in order to get people to buy healthy food,” he said. “People think, ‘Just tax soda and obesity will go away!’ What if soda costs 50 cents more? The person who would ordinarily buy soda may just substitute a fruit drink, an energy drink or a coffee drink, which is likely very similar to soda in terms of sugar and calories. In these debates, nobody accounts for the fact that there will be substitutions.”

The use of nutrition information, provided by the NuVal nutrition profiling system, also will be evaluated in the study. Epstein was involved in the development of NuVal, which uses an algorithm based on positive (fiber, vitamins, minerals) and negative (trans fats, salt, sugar) aspects of food to assign to each food a nutrition score. “We’re developing an evidence base for public policy decisions so that politicians can use the data to set public policy,” Epstein said in the release.