Supplemental File

Supplemental file

Title: The variation of healthy and unhealthy food prices across neighborhoods and their association with neighborhood socioeconomic status and proportion Black/Hispanic

Authors: David M. Kern, Amy H. Auchincloss, Lucy F. Robinson, Mark F. Stehr, Genevieve Pham-Kanter

Acknowledgement/Disclaimer: Mention of trade names, commercial practices, or organizations does not imply endorsement by the authors, the institutions where the authors work, nor by the funding entities. The authors take sole responsibility for all data analyses, interpretation, and views expressed in this paper. Any errors in the manuscript are the sole responsibility of the authors, not of Information Resources Inc. (IRI, who supplied the pricing dataset).

Table Number Page Number

Supplement Table 1 List of all brands and examples of products selected for the healthier and unhealthy food categories 2

Supplement Table 2 Food prices according to weights based on national consumption averages and equal weights 3

Supplement Table 3 Sensitivity analysis of the hierarchical models examining price outcomes on neighborhood socioeconomic status (SES) and the proportion of individuals who are Hispanic or black using a 2-mile buffer 4

Supplement Table 4 Price of each product category by demographic characteristics 5

Supplement Table 1 List of all brands and examples of products selected for the healthier and unhealthy food categories

Category / Number of brands / Number of UPCs / Brands / Example products / Exclusions *
Carbonated Beverages / 9 / 25 / 7-UP, A&W, Canada Dry, Coca Cola, Dr. Pepper, Mountain Dew, Pepsi, Sprite, Sunkist / 2-liter bottle, 12-pack of 12-ounce cans, 20-ounce bottle / Diet or reduced sugar sodas
Chocolate Candy / 11 / 22 / Hershey Milk Chocolate Bar, Hershey's Almond Chocolate Bar, Kit Kat, M&M, Milky Way, Nestle Crunch, Butter Finger, Almond Joy, Reese's cup, Rolo, Snickers, Three Musketeers, York / 1.55-ounce bar, 1.69-ounce package, 8 count bag, 11.18-ounce bag
Cookies / 4 / 13 / Keebler, Little Debbie, Nabisco, Pepperidge Farm / 10-ounce package 16.2-ounce package, 21.2-ounce package
Cottage cheese / 3 / 9 / Breakstone, Daisy, General Mills / 16-ounce 2% milk fat, 24-ounce 4% milk fat, 16-ounce 1% milk fat / Specialty products, such as lactose free cottage cheese
Orange juice / 3 / 12 / Florida's Natural, Simply, Tropicana / 13.5-ounce bottle, 59-ounce bottle, 89-ounce carton, 128-ounce container / Added sugar, not 100% orange juice
Milk / 5 / 14 / Farmland, Hood, Horizon, Organic Valley, Stonyfield / Skim, 1% or 2% milk in half-gallon or gallon containers / Full fat and non-dairy milks (e.g., soy, almond)
Frozen vegetables / 3 / 23 / Bird's Eye, Green Giant, Pictsweet / Peas 14.4-ounce bag, broccolli 24-ounce bag / Seasoned, glazed, creamed
Salty snacks / 10 / 23 / Bugles, Doritos, Funyuns, Lays, Pringles, Rold Gold, Baked Ruffles, Snyders of Hanover, Sunchips, Tostitos / 6.38-ounce pringles sour cream and onion, 17-ounce Doritos nacho cheese
Yogurt / 5 / 17 / Chobani, Dannon, Fage, Stonyfield, Yoplait / 6-ounce non-fat blueberry fruit on the bottom, 24-ounce light n fit vanilla, 6-ounce non-fat plain / Products marketed towards children (e.g., Trix brand yogurt) and/or highly sweetened (e.g., crunch and whips).

*Exclusions were made for substantive reasons (to better-align the product categories with either healthier or unhealthy foods/beverages) and/or to enhance comparability of the items within the product categories.

Supplement Table 2 Food prices according to weights based on national consumption averages and equal weights

All healthy food
(weight 1)* / All healthy food
(weight 2)**
Mean / SD / Mean / SD
Aggregate healthy food price / $0.590 / $0.056 / $0.619 / $0.065
Aggregate unhealthy food price / $0.298 / $0.024 / $0.294 / $0.021
Healthy-to-unhealthy price ratio / 1.99 / 0.19 / 2.11 / 0.21

*Weight 1: Aggregate healthy food prices and unhealthy food prices use weights according to national consumption estimates of frozen vegetables, fruit juice, and dairy for healthy foods, and sugar sweetened beverages, chocolate, cookies, and chips (potato, corn, etc.) for unhealthy food.

** Weight 2: Aggregate healthy food prices, unhealthy food prices use equal weights within each category (i.e., fruit juice / frozen vegetables and dairy each received a weight of 1/2 for the healthy food price; and soda, sweets, and salty snacks each received a weight of 1/3 for the unhealthy price

Estimate* / 95% CI
Model / Lower / Upper / P-value
SES MODELS:
Mean difference in price per 20 percent change in neighborhood socioeconomic index
Healthy food price / Unadjusted† / 0.00434 / 0.00320 / 0.00548 / <0.0001
Adjusted§ / 0.00073 / -0.00093 / 0.00240 / 0.3881
Fruit juice and frozen vegetables / Unadjusted† / 0.01342 / 0.01215 / 0.01469 / <0.0001
Adjusted§ / 0.01080 / 0.00890 / 0.01271 / <0.0001
Dairy / Unadjusted† / -0.01304 / -0.01514 / -0.01093 / <0.0001
Adjusted§ / -0.01869 / -0.02192 / -0.01546 / <0.0001
Unhealthy food price / Unadjusted† / 0.00035 / -0.00015 / 0.00085 / 0.1741
Adjusted§ / 0.00020 / -0.00049 / 0.00089 / 0.5649
Soda / Unadjusted† / 0.00038 / -0.00023 / 0.00098 / 0.2209
Adjusted§ / 0.00038 / -0.00057 / 0.00132 / 0.4357
Sweets / Unadjusted† / 0.00231 / 0.00145 / 0.00317 / <0.0001
Adjusted§ / 0.00107 / -0.00002 / 0.00215 / 0.0547
Salty snacks / Unadjusted† / -0.00226 / -0.00262 / -0.00191 / <0.0001
Adjusted§ / -0.00136 / -0.00192 / -0.00079 / <0.0001
Healthy-to-Unhealthy price ratio / Unadjusted† / 0.01218 / 0.00826 / 0.01610 / <0.0001
Adjusted§ / 0.00188 / -0.00447 / 0.00824 / 0.5615
BLACK/HISPANIC MODELS:
Mean difference in price per 20 percent change in neighborhood proportion of Black/Hispanic
Healthy price / Unadjusted† / -0.00295 / -0.00412 / -0.00178 / <0.0001
Adjusted§ / 0.00021 / -0.00148 / 0.00190 / 0.8071
Fruit juice and frozen vegetables / Unadjusted† / -0.01005 / -0.01141 / -0.00869 / <0.0001
Adjusted§ / -0.00013 / -0.00205 / 0.00180 / 0.8973
Dairy / Unadjusted† / 0.01067 / 0.00850 / 0.01284 / <0.0001
Adjusted§ / 0.00115 / -0.00214 / 0.00444 / 0.4925
Unhealthy price / Unadjusted† / 0.00079 / 0.00027 / 0.00130 / 0.0027
Adjusted§ / 0.00199 / 0.00128 / 0.00269 / <0.0001
Soda / Unadjusted† / 0.00035 / -0.00027 / 0.00096 / 0.2676
Adjusted§ / 0.00068 / -0.00028 / 0.00165 / 0.1669
Sweets / Unadjusted† / -0.00019 / -0.00108 / 0.00069 / 0.6671
Adjusted§ / 0.00344 / 0.00234 / 0.00455 / <0.0001
Salty snacks / Unadjusted† / 0.00231 / 0.00194 / 0.00267 / <0.0001
Adjusted§ / 0.00121 / 0.00064 / 0.00179 / <0.0001
Healthy-to-Unhealthy price ratio / Unadjusted† / -0.01546 / -0.01944 / -0.01148 / <0.0001
Adjusted§ / -0.01149 / -0.01798 / -0.00500 / 0.0005

*Estimate represents per 20 percentile change in neighborhood SES or Black/Hispanic

† Models did not include covariates but were adjusted for county and state via model nesting

§Includes covariates: Age, region, urbanicity, population density, supermarket density, toilet paper price, and either race (in the SES models) or neighborhood SES (in the race models).

Supplement Table 4 Price of each product category by demographic characteristics

Healthy foods / Unhealthy foods / Ratio
# of stores / Fruit juice and frozen vegetables / Dairy / All healthy food* / Soda / Sweets / Salty Snacks / All unhealthy food* / Healthy-to-
Unhealthy*
Mean / SD / Mean / SD / Mean / SD / Mean / SD / Mean / SD / Mean / SD / Mean / SD / Mean / SD
Overall / 1953 / $0.489 / $0.051 / $0.760 / $0.100 / $0.590 / $0.056 / $0.217 / $0.029 / $0.375 / $0.037 / $0.290 / $0.014 / $0.298 / $0.024 / $1.990 / $0.190
Neighborhood SES quantileⱡ
lowest quintile
(least advantaged) / 391 / $0.460 / $0.042 / $0.788 / $0.089 / $0.581 / $0.047 / $0.219 / $0.024 / $0.370 / $0.032 / $0.297 / $0.017 / $0.299 / $0.019 / 1.950 / 0.175
second quintile / 391 / $0.476 / $0.040 / $0.759 / $0.092 / $0.581 / $0.048 / $0.215 / $0.025 / $0.370 / $0.034 / $0.292 / $0.013 / $0.295 / $0.020 / 1.974 / 0.177
middle quintile / 390 / $0.487 / $0.039 / $0.760 / $0.102 / $0.589 / $0.053 / $0.213 / $0.024 / $0.373 / $0.028 / $0.288 / $0.011 / $0.295 / $0.017 / 2.003 / 0.196
fourth quintile / 391 / $0.496 / $0.040 / $0.747 / $0.106 / $0.590 / $0.057 / $0.213 / $0.025 / $0.373 / $0.026 / $0.285 / $0.011 / $0.294 / $0.016 / 2.014 / 0.204
highest quantile
(most advantaged) / 390 / $0.526 / $0.065 / $0.747 / $0.103 / $0.611 / $0.068 / $0.226 / $0.043 / $0.389 / $0.055 / $0.287 / $0.013 / $0.306 / $0.039 / 2.010 / 0.190
Proportion Black/Hispanic quintile
lowest quint.
(0.8% to 14.0% Bl/Hisp) / 390 / $0.501 / $0.060 / $0.741 / $0.086 / $0.592 / $0.058 / $0.216 / $0.039 / $0.378 / $0.047 / $0.286 / $0.013 / $0.297 / $0.033 / $2.002 / $0.182
2nd quint.
(14.0% to 24.0%) / 392 / $0.499 / $0.051 / $0.743 / $0.096 / $0.591 / $0.058 / $0.219 / $0.031 / $0.375 / $0.037 / $0.288 / $0.012 / $0.298 / $0.026 / $1.990 / $0.187
middle quint.
(24.0% to 37.8%) / 390 / $0.494 / $0.045 / $0.760 / $0.112 / $0.593 / $0.060 / $0.216 / $0.026 / $0.374 / $0.034 / $0.289 / $0.012 / $0.297 / $0.022 / $2.004 / $0.203
4th quint.
(37.9% to 58.4%) / 391 / $0.486 / $0.046 / $0.759 / $0.102 / $0.587 / $0.054 / $0.217 / $0.024 / $0.373 / $0.032 / $0.292 / $0.013 / $0.297 / $0.019 / $1.981 / $0.194
highest quint.
(58.5% to 98.8%) / 390 / $0.465 / $0.046 / $0.798 / $0.090 / $0.588 / $0.050 / $0.217 / $0.023 / $0.374 / $0.033 / $0.294 / $0.017 / $0.299 / $0.018 / $1.974 / $0.184
Urban classification
Large metro (pop. ≥1 million) / 1606 / $0.492 / $0.055 / $0.769 / $0.102 / $0.596 / $0.058 / $0.217 / $0.031 / $0.377 / $0.039 / $0.288 / $0.013 / $0.298 / $0.026 / $2.007 / $0.192
Small metro (pop. <1 million) / 296 / $0.476 / $0.028 / $0.725 / $0.083 / $0.568 / $0.042 / $0.221 / $0.018 / $0.368 / $0.027 / $0.296 / $0.013 / $0.298 / $0.015 / $1.912 / $0.163
Rural (pop <50k) / 51 / $0.467 / $0.019 / $0.701 / $0.055 / $0.553 / $0.023 / $0.217 / $0.018 / $0.354 / $0.026 / $0.301 / $0.014 / $0.291 / $0.015 / $1.904 / $0.139
Region
Northeast / 207 / $0.509 / $0.087 / $0.730 / $0.095 / $0.594 / $0.074 / $0.237 / $0.056 / $0.396 / $0.069 / $0.288 / $0.016 / $0.314 / $0.052 / $1.912 / $0.179
Midwest / 173 / $0.489 / $0.032 / $0.782 / $0.038 / $0.599 / $0.026 / $0.172 / $0.020 / $0.383 / $0.034 / $0.277 / $0.011 / $0.279 / $0.014 / $2.155 / $0.106
South / 1009 / $0.468 / $0.024 / $0.703 / $0.052 / $0.555 / $0.024 / $0.217 / $0.019 / $0.365 / $0.030 / $0.296 / $0.013 / $0.295 / $0.018 / $1.888 / $0.138
West / 564 / $0.519 / $0.057 / $0.867 / $0.090 / $0.650 / $0.043 / $0.225 / $0.015 / $0.382 / $0.026 / $0.283 / $0.007 / $0.302 / $0.013 / $2.152 / $0.143

*Composite healthy and unhealthy food prices were weighted based on national consumption averages of each food category

ⱡ Neighborhood SES was derived from log of the median household income; log of the median value of housing units; the percentage of households receiving interest, dividend, or net rental income; the percentage of adults 25 years of age or older who had completed high school; the percentage of adults 25 years of age or older who had completed college; and the percentage of employed persons 16 years of age or older in executive, managerial, or professional specialty occupations.