Longitudinal study of the effects of price and promotion incentives on purchases of unhealthy foods: evidence for restricting food promotions
Longitudinal study of the effects of price and promotion incentives on purchases of unhealthy foods: evidence for restricting food promotions
Objectives: taxes and restrictions on promotions have recently been proposed as policy instruments to reduce consumption of unhealthy foods. The objective of this study is to add to the limited evidence on the comparative effectiveness of price changes, price promotions and volume promotions in changing household purchasing of unhealthy foods, using biscuits, crisps and savoury snacks as examples.
Design: longitudinal regression analysis of consumer microdata.
Setting: secondary data on itemised household purchases of biscuits, crisps and savoury snacks from 2006 to 2012.
Participants: sample of 3024 households in Scotland.
Main outcome measures: changes in the number of calories (kcal) purchased in the product category by a household caused by changes in the price for the product category, any temporary in-store price promotions and any temporary in-store volume promotions. Changes are measured at the mean, median, 25th percentile and 75th percentile of the household purchasing distribution for the full sample. Subgroup analyses were conducted by household income band and for households with and without children.
Results: between product categories, the scale of purchasing response to incentives varies significantly. Within product categories, the mean calories (kcal) purchased by a household are more responsive to any volume promotion than to price or any price promotion for all product categories. As the volume of items purchased increases, households are less responsive to price, less responsive to any volume promotion and more responsive to any price promotion. Statistically significant differences are observed between household income groups in their response to price and promotion incentives within the biscuits category only. In cases where statistically significant differences are observed, households with children are more responsive to promotion and price incentives than households without children.
Conclusions: for all product categories analysed (biscuits, crisps and savoury snacks), household purchasing is most responsive to any volume promotion. Therefore, assuming the response of consumers to incentives remains constant following legislation, the most effective policy instrument to reduce the calorie intake from these products may be a ban on volume promotions.
dietary patterns
e000323
Kopasker, Daniel
be02d738-6cc5-43a1-bff2-1cbcf230ecf4
Ejebu, Ourega-Zoé
4f545ae3-4823-44ab-8d59-185d30929ada
Norwood, Patricia
9fc7cb28-ef78-45ea-b7ec-da356c3d67ae
Ludbrook, Anne
2f1696b9-4b8c-4d7d-a2e7-1a9a0b50327e
1 June 2022
Kopasker, Daniel
be02d738-6cc5-43a1-bff2-1cbcf230ecf4
Ejebu, Ourega-Zoé
4f545ae3-4823-44ab-8d59-185d30929ada
Norwood, Patricia
9fc7cb28-ef78-45ea-b7ec-da356c3d67ae
Ludbrook, Anne
2f1696b9-4b8c-4d7d-a2e7-1a9a0b50327e
Kopasker, Daniel, Ejebu, Ourega-Zoé, Norwood, Patricia and Ludbrook, Anne
(2022)
Longitudinal study of the effects of price and promotion incentives on purchases of unhealthy foods: evidence for restricting food promotions.
BMJ Nutrition, Prevention & Health, 5 (1), .
(doi:10.1136/bmjnph-2021-000323).
Abstract
Objectives: taxes and restrictions on promotions have recently been proposed as policy instruments to reduce consumption of unhealthy foods. The objective of this study is to add to the limited evidence on the comparative effectiveness of price changes, price promotions and volume promotions in changing household purchasing of unhealthy foods, using biscuits, crisps and savoury snacks as examples.
Design: longitudinal regression analysis of consumer microdata.
Setting: secondary data on itemised household purchases of biscuits, crisps and savoury snacks from 2006 to 2012.
Participants: sample of 3024 households in Scotland.
Main outcome measures: changes in the number of calories (kcal) purchased in the product category by a household caused by changes in the price for the product category, any temporary in-store price promotions and any temporary in-store volume promotions. Changes are measured at the mean, median, 25th percentile and 75th percentile of the household purchasing distribution for the full sample. Subgroup analyses were conducted by household income band and for households with and without children.
Results: between product categories, the scale of purchasing response to incentives varies significantly. Within product categories, the mean calories (kcal) purchased by a household are more responsive to any volume promotion than to price or any price promotion for all product categories. As the volume of items purchased increases, households are less responsive to price, less responsive to any volume promotion and more responsive to any price promotion. Statistically significant differences are observed between household income groups in their response to price and promotion incentives within the biscuits category only. In cases where statistically significant differences are observed, households with children are more responsive to promotion and price incentives than households without children.
Conclusions: for all product categories analysed (biscuits, crisps and savoury snacks), household purchasing is most responsive to any volume promotion. Therefore, assuming the response of consumers to incentives remains constant following legislation, the most effective policy instrument to reduce the calorie intake from these products may be a ban on volume promotions.
Text
A longitudinal study of the effects of price and promotion incentives on purchases of unhealthy foods
- Accepted Manuscript
Text
bmjnph-2021-000323.full
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More information
Accepted/In Press date: 16 February 2022
Published date: 1 June 2022
Additional Information:
Funding Information:
This work was supported by the Scottish Government Rural and Environment Science and Analytical Services division and the Chief Scientist Office of the Scottish Government Health and Social Care Directorates.
Funding Information:
The research was predominantly undertaken while all authors were employed within the Health Economics Research Unit, University of Aberdeen. The Health Economics Research Unit is supported by the Chief Scientist Office of the Scottish Government Health and Social Care Directorates. This work was supported by a grant to The Rowett Institute from the Scottish Government Rural and Environment Science and Analytical Services division. DK was also funded by the Medical Research Council (MC_UU_00022/2) and the Scottish Government Chief Scientist Office (SPHSU17).
Publisher Copyright:
©
Keywords:
dietary patterns
Identifiers
Local EPrints ID: 455814
URI: http://eprints.soton.ac.uk/id/eprint/455814
PURE UUID: fdc789db-fe85-4fa9-8baf-65b60507bd0b
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Date deposited: 05 Apr 2022 17:21
Last modified: 24 May 2024 02:00
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Contributors
Author:
Daniel Kopasker
Author:
Patricia Norwood
Author:
Anne Ludbrook
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