Variety may trump virtue when it comes to the struggle to eat healthy, says a Vanderbilt marketing professor who studies consumer self-control and endorses “vice-virtue bundles” combining nutritious and not-so-nutritious foods.

“We suggest a simple … solution that can help consumers who would otherwise choose vice over virtue to simultaneously increase consumption of healthy foods (virtues) and decrease consumption of unhealthy foods (vices) while still fulfilling taste goals – ‘vice-virtue bundles,’” Kelly L. Haws, associate professor of management at Vanderbilt’s Owen Graduate School of Management, said.

The idea is to not give up entirely foods that provide pleasure but aren’t nutritious. Instead, the focus should be on lowering the portion of the “vice” foods and correspondingly raising the portion of a healthy food to replace it.

In a series of experiments, Haws and her colleagues found that people have a “taste-health balance point” – a proportion of vice and virtuous foods that make up one serving – which they find satisfactory. For most, the perfect vice-virtue bundle is made up of a small (1/4) to medium (1/2) portion of vice. So if a vice-virtue bundle was made up of fries and slices of apple, it might take a small or very small serving of fries to satiate the need for the vice food.

Haws is among five researchers who lay out their findings in “Vice-Virtue Bundles,” a paper under review for publication.

Vice-virtue bundles could also be the answer for many in the food service industry who are actively seeking out healthy food options that consumers will voluntarily choose, Haws said.

“Given that consumers consistently find vice-virtue bundles to be attractive, managers should consider adding vice-virtue bundles to their product lines,” Haws said. “For restaurants and food vendors that already offer pure vice and virtue options, vice – virtue bundles provide an opportunity for product line expansion through existing items rather than through development of completely new offerings.

“This provides a potential opportunity for cost-savings, as many food establishments devote considerable resources to developing new product offerings, which can in turn increase inventory or production costs.”

This round of research did not mix in any pricing or marketing components, but the researchers say it would be easy for restaurants to pursue such experiments on their own.

“With the right marketing and the right choice sets, we believe that vice-virtue bundles offer exciting directions for future research and practice aimed at maximizing health without compromising tastes,” the researchers concluded.

Haws’ research interests are related to consumer behavior, with a focus on issues relevant to consumer welfare, specifically with respect to food/health and financial decision making. Her interests include consumer self-control, strategies for improving food consumption and behavioral pricing.

Haws’ co-authors of “Vice-Virtue Bundles” are Peggy J. Liu, Ph.D candidate at Fuqua School of Business at Duke University; Cait Lamberton, associate professor of business administration at Joseph M. Katz Graduate School of Business at the University of Pittsburgh; Gavan J. Fitzsimons, R. David Thomas Professor of Marketing and Psychology at Fuqua School of Business at Duke University; and Troy H. Campbell, a Ph.D. candidate at Fuqua School of Business at Duke University.