Assessing the variety and pricing of selected foods in socioeconomically disparate districts of Berlin, Germany

Assessing the Cost of Healthy and Unhealthy Diets: A Systematic Review of Methods

PURPOSE OF REVIEW

Poor diets are a leading risk factor for chronic disease globally. Research suggests healthy foods are often harder to access, more expensive, and of a lower quality in rural/remote or low-income/high minority areas. Food pricing studies are frequently undertaken to explore food affordability. We aimed to capture and summarise food environment costing methodologies used in both urban and rural settings.

RECENT FINDINGS

Our systematic review of high-income countries between 2006 and 2021 found 100 relevant food pricing studies. Most were conducted in the USA (n = 47) and Australia (n = 24), predominantly in urban areas (n = 74) and cross-sectional in design (n = 76). All described a data collection methodology, with just over half (n = 57) using a named instrument. The main purpose for studies was to monitor food pricing, predominantly using the 'food basket', followed by the Nutrition Environment Measures Survey for Stores (NEMS-S). Comparatively, the Healthy Diets Australian Standardised Affordability and Price (ASAP) instrument supplied data on relative affordability to household incomes. Future research would benefit from a universal instrument reflecting geographic and socio-cultural context and collecting longitudinal data to inform and evaluate initiatives targeting food affordability, availability, and accessibility.

Comparison of food and beverage products' availability, variety, price and quality in German and US supermarkets

Objective:

To assess availability, variety, price and quality of different food products in a convenience sample of supermarkets in Germany and the USA.

Design:

Cross-sectional study using an adapted version of the Bridging the Gap Food Store Observation Form.

Setting:

Information on availability, quality, price and variety of selected food products in eight German and seven US supermarkets (discount and full service) was obtained and compared by country.

Results:

A general tendency for lower prices of fruits and vegetables in Germany was observed, while produce quality and variety did not seem to differ between countries, with the exception of the variety of some vegetables such as tomatoes. Chips and cereals did not differ significantly in variety nor price. In both countries, high energy-dense foods were lower in energy costs than lower energy-dense foods.

Conclusions:

The influence of food prices and availability on consumption should be further explored, including the impact of country differences.

Indicators of the relative availability of healthy versus unhealthy foods in supermarkets: a validation study

Background

In-store availability of healthy and unhealthy foods may influence consumer purchases. Methods used to measure food availability, however, vary widely. A simple, valid, and reliable indicator to collect comparable data on in-store food availability is needed.

Methods

Cumulative linear shelf length of and variety within 22 healthy and 28 unhealthy food groups, determined based on a comparison of three nutrient profiling systems, were measured in 15 New Zealand supermarkets. Inter-rater reliability was tested in one supermarket by a second researcher. The construct validity of five simple indicators of relative availability of healthy versus unhealthy foods was assessed against this ‘gold standard’.

Results

Cumulative linear shelf length was a more sensitive and feasible measure of food availability than variety. Four out of five shelf length ratio indicators were significantly associated with the gold standard (ρ = 0.70–0.75). Based on a non-significant difference from the ‘gold standard’ (d = 0.053 ± 0.040) and feasibility, the ratio of cumulative linear shelf length of fresh and frozen fruits and vegetables versus soft and energy drinks, crisps and snacks, sweet biscuits and confectionery performed best for use in New Zealand supermarkets.

Conclusions

Four out of the five shelf length ratio indicators of the relative availability of healthy versus unhealthy foods in-store tested could be used for future research and monitoring, but additional validation studies in other settings and countries are recommended. Consistent use of those shelf length ratio indicators could enhance comparability of supermarket food availability between studies, and help inform policies to create healthy consumer food retail environments.

Electronic supplementary material

The online version of this article (doi:10.1186/s12966-017-0512-0) contains supplementary material, which is available to authorized users.