Experimental analysis of the effect of taxes and subsides on calories purchased in an on-line supermarket

doi:10.1016/j.appet.2015.06.020

Appetite

Volume 95, 1 December 2015, Pages 245-251

https://doi.org/10.1016/j.appet.2015.06.020 Get rights and content

Highlights

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There is limited research on pricing effects on overall dietary intake.
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Taxes reduced the purchase of taxed foods.
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Subsidies increased the purchase of subsidized foods.
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Neither taxes nor subsidies reduced calories purchased.
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Subsidies improved food quality purchased.

Abstract

Taxes and subsidies are a public health approach to improving nutrient quality of food purchases. While taxes or subsidies influence purchasing, it is unclear whether they influence total energy or overall diet quality of foods purchased. Using a within subjects design, selected low nutrient dense foods (e.g. sweetened beverages, candy, salty snacks) were taxed, and fruits and vegetables and bottled water were subsidized by 12.5% or 25% in comparison to a usual price condition for 199 female shoppers in an experimental store. Results showed taxes reduced calories purchased of taxed foods (coefficient = −6.61, CI = −11.94 to −1.28) and subsidies increased calories purchased of subsidized foods (coefficient = 13.74, CI = 8.51 to 18.97). However, no overall effect was observed on total calories purchased. Both taxes and subsidies were associated with a reduction in calories purchased for grains (taxes: coefficient = −6.58, CI = −11.91 to −1.24, subsidies: coefficient = −12.86, CI = −18.08 to −7.63) and subsidies were associated with a reduction in calories purchased for miscellaneous foods (coefficient = −7.40, CI = −12.62 to −2.17) (mostly fats, oils and sugars). Subsidies improved the nutrient quality of foods purchased (coefficient = 0.14, CI = 0.07 to 0.21). These results suggest that taxes and subsidies can influence energy purchased for products taxed or subsidized, but not total energy purchased. However, the improvement in nutrient quality with subsidies indicates that pricing can shift nutritional quality of foods purchased. Research is needed to evaluate if differential pricing strategies based on nutrient quality are associated with reduction in calories and improvement in nutrient quality of foods purchased.

Section snippets

Participants

Participants were 199 women, recruited from an existing family database, flyers posted around the University at Buffalo campuses and in the community, web based recruitment (e.g ads on Craig's list and on the department's website) and targeted direct mailings. Inclusion criteria included: females 19 years of age or older and the primary grocery shopper for a household containing at least one child between the ages of 2 and 18, who purchased the majority of their groceries once a week or could

Results

Participant characteristics are shown in Table 2. The amount individuals spent in the online store during the usual shopping condition (no tax or subsidy, $118.77) was related to the amount spent in usual shopping as assessed by baseline receipts ($110.73) provided by participants (r = 0.59, p < 0.0001), but the amount of money spent during experimental shopping was less than that spent during usual shopping F (1,198) = 5.19, p = 0.02. Within the experimental shopping platform, there were no

Discussion

This study found that healthy food subsidies were effective in increasing calories purchased for subsidized foods and improving nutrient quality of food purchased, but not in changing total calories purchased. Taxes reduced calories purchased for taxed foods, but neither reduced overall calories purchased or improved the nutrient quality of food purchased. This lack of effect on total calories purchased may be due to the fact that the proportion of foods that were taxed (12.7%) or subsidized

Acknowledgements

This research was registered at http:www.clinicaltrials.gov as NCT01619787. This research was funded in part by a grant from the National Institute of Child Health and Human Development R01 HD057975 awarded to Dr. Epstein. Appreciation is expressed to Lauren Nitecki, Georgiana Pascanu, Kirstie Clune, Andrew Pittner, Patrick Vanini, Erin Brewer-Spritzer and Tinuke Oluyomi Daniel for assistance in running the study. Dr. Epstein is a consultant to and has equity in Kurbo. The other authors have no

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Diet is an important determinant of health, and food purchasing is a key antecedent to consumption.
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Experimental analysis of the effect of taxes and subsides on calories purchased in an on-line supermarket

Highlights

Abstract

Section snippets

Participants

Results

Discussion

Acknowledgements

American Journal of Clinical Nutrition

American Journal of Clinical Nutrition

American Journal of Clinical Nutrition

Advances in Nutrition

Journal of Health Economics

Journal of Nutrition

Journal of Nutrition

Appetite

American Journal of Clinical Nutrition

Journal of Nutrition

Appetite

Health & Place

American Journal of Clinical Nutrition

Appetite

Preventive Medicine

Effectiveness of subsidies in promoting healthy food purchases and consumption: a review of field experiments

Public Health Nutrition

Effectiveness of subsidies in promoting healthy food purchases and consumption: a review of field experiments

Public Health Nutrition

The impact of food prices on consumption: a systematic review of research on the price elasticity of demand for food

American Journal of Public Health

Evaluation of the healthy incentives pilot (HIP): Final report