Testing effects of combining incentives, restrictions in food benefit program

A clinical trial that mimicked a food benefit program and paired incentives for buying fruits and vegetables with restrictions on sugary foods found that participants ate fewer calories, less sugary foods, more solid fruit and had better scores on an index that assessed consistency with dietary guidelines, according to a new report published online by JAMA Internal Medicine.

About 1 in 7 Americans participated in the Supplement Nutrition Assistance Program (SNAP), formerly known as the Food Stamp Program, at some point in 2015. There is interest in finding ways SNAP can better help families buy the food they need for good health. A variety of modifications to the program have been proposed, including incentives for buying fruits and vegetables and restrictions on buying less nutritious foods with program funds.

For legal reasons, it is not possible to alter practices in the actual SNAP program, so Lisa Harnack, Dr.P.H., of the University of Minnesota, Minneapolis, and coauthors recruited adults for a clinical trial who were near eligible for SNAP or eligible for SNAP but not currently participating.

Lower-income participants were given debit cards loaded with an amount of food benefits similar to what they would have received from SNAP every four weeks over the 12-week experiment period. For example, benefits were $152 monthly for a household of one, $277 for two people and $401 for three people in a household.

Study participants (n=279) were assigned to 1 of 4 experimental financial food benefit groups: an incentive of 30 percent of the purchase price of fruits and vegetables; a restriction on buying sugar-sweetened beverages, sweet baked goods or candies with benefits; the incentive plus the restriction; or a control group with no incentive or restrictions on food purchased with benefits.

Dietary recall was used to measure intake of calories, discretionary calories and overall quality of diet.

The incentive plus restriction condition on food benefits compared with the control group reduced calorie intake, lowered the intake of discretionary calories, reduced intake of sugar-sweetened beverages, baked good and candies, increased the intake of solid fruit, and improved scores on a healthy eating index that assessed consistency with dietary guidelines, according to the results. Fewer improvements were seen when participants had only the incentive or restrictions, the authors report.

Study limitations include the representativeness of the study group because actual SNAP participants may respond differently.

"These results suggest that a food benefit program that pairs financial incentives for the purchasing of fruits and vegetables with restrictions on the purchase of less nutritious foods may reduce energy intake and improve the nutritional quality of the diet of program participants in comparison with a food benefit program that does not include incentives and restrictions," the paper concludes.