Prenticemarketing School Milk to Children a Review of Key Findings From the School Milk Pilot Test

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Chocolate Milk Consequences: A Airplane pilot Study Evaluating the Consequences of Banning Chocolate Milk in School Cafeterias

• David R. Merely,
• Brian Wansink

Chocolate Milk Consequences: A Airplane pilot Study Evaluating the Consequences of Banning Chocolate Milk in School Cafeterias

• Andrew S. Hanks,
• David R. Just,
• Brian Wansink

ten

• Published: April 16, 2014
• https://doi.org/x.1371/journal.pone.0091022

Figures

Abstract

Objectives

Currently, 68.three% of the milk available in schools is flavored, with chocolate being the most popular (61.6% of all milk). If chocolate milk is removed from a school cafeteria, what will happen to overall milk selection and consumption?

Methods

In a earlier-after study in 11 Oregon uncomplicated schools, flavored milk–which will be referred to every bit chocolate milk–was banned from the cafeteria. Milk sales, school enrollment, and data for daily participation in the National School Lunch Program (NSLP) were compared twelvemonth to engagement.

Results

Full daily milk sales declined past 9.9% (p<0.01). Although white milk increased by 161.ii cartons per twenty-four hour period (p<0.001), 29.4% of this milk was thrown away. Eliminating chocolate milk was also associated with 6.viii% fewer students eating schoolhouse lunches, and although other factors were likewise involved, this is consistent with the notion of psychological reactance.

Conclusions

Removing chocolate milk from school cafeterias may reduce calorie and sugar consumption, but it may also atomic number 82 students to have less milk overall, potable less (waste more) of the white milk they do have, and no longer purchase school tiffin. Food service managers need to carefully weigh the costs and benefits of eliminating chocolate milk and should consider culling options that make white milk more user-friendly, bonny, and normal to choose.

Commendation: Hanks As, Just DR, Wansink B (2014) Chocolate Milk Consequences: A Pilot Report Evaluating the Consequences of Banning Chocolate Milk in School Cafeterias. PLoS ONE 9(4): e91022. https://doi.org/10.1371/journal.pone.0091022

Editor: Amanda Bruce, University of Missouri-Kansas City, Us of America

Received: July nineteen, 2013; Accepted: Feb 5, 2014; Published: April 16, 2014

Copyright: © 2014 Hanks et al. This is an open-access commodity distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Funding: There were two grants which were sources of funding for this report, USDA ERS/FNS 59-5000-0-0090, and USDA NIFA/Hatch 002254837. The funders had no role in study pattern, information drove and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have the following interests: Brian Wansink & Andrew Hanks received funding during the assay stage of "Happier Meals: New Children's Meals Lead to Fewer Purchased Calories" from September 2012 through Dec 2012. Brian Wansink became a member of the McDonald'due south Advisory Council in January 2012. Bantam Dell–royalties from the book, Mindless Eating. Blueish Zones Keynote & Panel Project in Los Angeles: Gave paid lectures on food psychology research conducted over the past 20 years. PKF Consulting: Acted as paid consultant on a project that PKF conducted for the Department of Defense related to improving overall health of war machine bases. Unilever: Gave paid lectures on food psychology research conducted over the past 20 years. In regards to the Mindless Products and Mindless Method, Dr. Wansink is not affiliated with either. Both projects were private ventures based upon Dr. Wansink's prior studies, merely he is not connected to them and receives no royalties or payment. David R. Just has no competing interests to report. All external funding for studies were derived from USDA, or various state level departments of health. This does not alter the authors' adherence to all the PLOS Ane policies on sharing data and materials.

Introduction

Chocolate milk tin have upwardly to twice as much carbohydrate as white milk and as a result, removing chocolate milk from school cafeterias has been actively debated as a mensurate to reduce childhood obesity. In response, many school districts have begun to limit or ban the sale of chocolate milk in hopes of reducing students' total caloric and sugar intake. [i] In contrast, the predominant view of nutrition and medical researchers is that milk has nutrients essential for bone growth and development, [two], [3], [4], [five], [6] leading other school districts to take the position that any milk is improve than no milk. [7], [viii], [ix] What is not known, nevertheless, is whether or not irresolute the availability of chocolate milk would influence other behaviors such as inside-meal compensation [10] or after-schoolhouse snacking patterns. [seven], [11], [12], [thirteen] Furthermore, restricting the availability of chocolate milk may lead to adverse economic impacts such as increased milk waste and decreased lunch sales. In general, all flavored milk with added sugar, including chocolate, strawberry, and vanilla, comprises 68.3% of all milk available in schools. [14] Since chocolate milk is the near common flavour (61.6% of all milk and 90.2% of flavored milk [14]) we will refer to all types of flavored milk as chocolate milk.

Of the students who purchase lunches served equally part of the National Schoolhouse Lunch Program (NSLP), 2-thirds choose chocolate over white milk [fifteen], [16]. Because most students drink chocolate milk for taste rather than nutrition [17], banning chocolate milk might not lead students to immediately substitute over to white milk. Fortunately, making white milk the default choice, and making chocolate milk less convenient without eliminating it, could increase white milk selection immediately, and with niggling controversy. [18], [19].

Methods

Written report Blueprint and Data

This pilot study took place in 11 elementary schools inside a single Oregon schoolhouse commune. Total population in the district is roughly 157,000 adults and students, and 85% are Caucasian, 7.eight% are of Hispanic or Latino origin, and 1.four% are African American. Median household income is $41,326, compared to the national median of $52,762, and 21.5% of the individuals in the district are below the poverty level, compared to the 14.3% national average.

In the 2011–12 school yr, school food service in the district removed chocolate milk in grades M-5 and offered skim milk instead. This offers a before versus after evaluation opportunity to explore differences in milk sales later on decision-making for changes in enrollment betwixt the 2010–2011 school year and the 2011–2012 school yr. To appraise the potential bear upon of removing chocolate milk on student behavior, milk sales information were collected during the months of September and Oct of both school years. September and October were selected because initially the school board had planned to re-introduce chocolate milk after the 2-month trial period. Nonetheless, afterward Oct, the board decided to go along the policy, though data drove stopped. For the months during the written report, the school district provided data for average daily participation rates, overall school enrollment, and percent of students receiving a free or reduced toll lunch. Given milk sales data and school enrollment, behavioral changes can be evaluated between the two school years.

Aggregate daily milk waste data were also collected in all but ane of the elementary schools during the September and Oct 2011–2012 school yr. Later on students had completed their meals, they poured their milk, both white and chocolate, into a divide bucket located next to the garbage receptacles. These waste matter measures were reported as gallons dumped, from which the number of 8-oz cartons wasted can be calculated.

Since milk waste product information were not collected in the study schools during the 2010–2011 schoolhouse twelvemonth, we compare waste in 2011–2012 to waste material measures from 15 other elementary schools from the Midwestern and Eastern Us. From these 15 simple schools we generated two baseline waste measures. The starting time baseline measure of milk waste material was derived from milk waste material data collected during the spring of 2012 in 5 of the 15 elementary schools, which were located in New York Country. Additional comparison measures were generated from 10 elementary schools from 10 states in the Midwestern and Eastern Us (non including New York Land). These measures were collected during the fall of 2012 when chocolate milk was restricted to the fatty free diverseness.

Milk waste at all 15 schools was collected using the Quarter-Waste product Method [xx], a reliable visual estimation technique for measuring tray waste in schoolhouse cafeterias. Waste material estimates from this Quarter-Waste Method are highly correlated with standard weighing techniques used to measure waste matter, with estimated correlation coefficients in excess of 0.90. Moreover, the Quarter-Waste Method generates a mean waste matter that is inside one gram of the amount obtained past weighing milk waste material [twenty].

Removal of chocolate milk was not the just change in this Oregon school commune. In the 2010–2011 schoolhouse yr, this school district had a full of 21 elementary schools. Considering of enrollment decreases, four of these schools airtight prior to the 2011–2012 school yr. The remaining students were transferred to other elementary schools in the district, causing wide swings in enrollment (greater than 35% increases) in four of these schools. In addition, two of the schools did not provide data for assay, thus reducing the number of elementary schools in the analysis to 11 schools.

In addition, in that location were various changes within the schoolhouse's food service. First, at the onset of the 2011–2012 schoolhouse year, lunch menu cycles changed from a 5-week to a four-week cycle, reducing the multifariousness of meals, peculiarly entrées, offered. Parental and student demand, withal, led to more frequent offerings of popular entrées such equally pizza, tacos, burgers, and breaded chicken products. Bonus items, such as cookies (offered every other Friday), pickles, croutons, cracker products, breadsticks, and whipped topping were also removed. A vegetable side was included with each entrée on a daily footing. In combination with these menu changes the lunch price increased from $2.25 to $2.50 per meal for the full price tiffin, most probable decreasing the number of full priced lunches purchased. Notably, cafeterias in the participating unproblematic schools provided beverage choices of bottle water, milk, and juice to students. No competitive foods (items not sold as function of the National School Tiffin Program – NSLP) were available.

Analysis

In order to better sympathize the potential impact that removing chocolate milk has on milk sales and intake, the relevant research questions were studied in two phases. First, schoolhouse level data were used to compare average milk sales betwixt the two school years to determine whether purchases of i% and fatty complimentary milks in the 2011–2012 school year beginning the impact on milk sales from eliminating chocolate milk. In each of these comparisons, mixed effects regression methods were used with random effects at the schoolhouse level. Milk sales for all milk, 1%, milk, fat free milk, and chocolate milk were used as dependent variables in separate regressions. A dummy variable for twelvemonth captured the impact from the alter in milk options and a monthly control was as well included in the analysis to account for seasonal variation.

Second, comparisons in milk waste matter information were studied using an unequal sample size, diff variance t-test and the degrees of freedom for the exam were calculated using the Welch-Satterthwait equation [21]. Since milk waste in the second set of comparison schools was measured differently, an unpaired t-examination of the difference in percent milk wasted is an advisable statistical method. In addition, allowing for diff variances provides a sensitivity check. Analyses were conducted using Stata 12.

Results

As a result of the policy, boilerplate sales per school of chocolate milk dropped from 190.4 to 0 (Table ane; Effigy 1). Interestingly, 90.1% of chocolate milk sales were recovered by 1% fat and skim white milk options. Indeed, following the elimination of chocolate milk boilerplate daily sales per school of white milk increased by 152% between the two school years (from 105.nine to 267.1 cartons; p<0.001; Table ii; Figure 1). This increase suggests that many students were willing to substitute 1% or skim white milk for chocolate milk. Still, an average of 30 fewer units of milk were sold each mean solar day in Sep and Oct of 2011, suggesting that approximately 30 of the 380 students (average enrollment) no longer chose the nutritious drink. This translates to a 9.9% decrease in milk choice (p<0.01; Table i).

In all schools nation wide, milk is served as a beverage pick for reimbursable meals as well as for purchase a la menu. In terms of full student enrollment (not restricting the pupil body to NSLP participants), there was an 8.two% decline (p<0.001; Tabular array ii; Figure 2) in the proportion of students who took milk. When chocolate milk was still an option, 77.8% of all students took milk. One time chocolate milk was removed, 71.iv% took milk.

When comparison milk types between the school years, there was a 113.9% increase (p<0.001; Table 2; Figure 2) in the percentage of enrolled students taking 1% milk. Moreover, the percentage of students selecting a milk blazon other than 1% white–including fat free chocolate in the 2010–2011 school year and fat free white in the 2011–2012 school year–decreased by 76.two%. Nutritional benefits to eliminating chocolate milk are an boilerplate decrease of 8 grams of carbohydrate and 37 calories in a student'south lunch (non necessarily consumed). These benefits, nonetheless, come at a price of 1 gram of protein, a decrease of 5 percentage points in the daily recommended intake of calcium, and an additional ½ gram of fat per boilerplate educatee's lunch.

Even though sales data advise many students willingly substituted chocolate for white milk, sales alone provide no indication whether or not students drank the lower calorie 1% or skim milk on their trays. Using milk waste matter data, we examine the corporeality of milk wasted when just white milk was offered. Cafeteria staff nerveless information on full gallons of milk wasted each day in September and October of the 2010–2011 school yr. On average, students wasted 40.nine% of the milk they selected.

Since milk waste was not collected during the school year when chocolate milk was still available, milk waste data in v unproblematic schools located in New York City were used as a comparison. In these schools, chocolate milk was still bachelor. These elementary schoolhouse students wasted an average of 31.vii% of the milk they took. This suggests that eliminating chocolate milk can increase full milk waste past 29.4% (p<0.001; Effigy 3). Based on this finding, for each boosted carton of white milk taken, an additional $0.02 was thrown away, increasing the cost of white milk per ounce consumed by x.0%. Milk waste matter nerveless from a broader set of schools in the fall of 2012 signal that 30.0% of all milk was wasted in these schools. This provides supportive evidence that the 31.seven% milk waste from the schools in New York State is a valid, and perhaps a bourgeois measurement.

Finally, Table 3 provides enrollment and lunch sales data for the schools in the study. Between the 2010–2011 and 2011–2012 school years, average enrollment in the schools nosotros studied remained stable (381.3 to 379.7 students – Table 1). Notably, however, there was a vi.8% turn down (p<0.05) in NSLP participation between the two years (Tabular array 1). While it is plausible that this decline can exist attributable to eliminating chocolate milk, other contemporaneous confounds inhibit our ability to identify one specific cause. Still, a powerful insight, consistent with reactance theory, is that eliminating chocolate milk could decrease the number of students ordering lunches by 6.8%.

Word

This natural experiment was afforded by eleven uncomplicated schools, all of which made a clean transition from offering chocolate milk to only white milk. Although the results are limited by the absence of control schools and may not be generalizable in magnitude to middle schools and high schools, these results offering important preliminary insights related to possible economic consequences of eliminating chocolate milk. Amongst these schools, eliminating chocolate milk was associated with a 9.ix% subtract in boilerplate daily milk sales, a 10.0% increase in the cost of milk consumption, and a 29.4% increment in milk waste. Although eliminating chocolate milk can reduce the corporeality of sugar and calories available in a student's lunch, it may too have unintended negative consequences to consider.

Every bit a airplane pilot study, these findings are not without limitations. Kickoff, other changes to the school district introduced potential confounds to the assay, all the same the mixed regression design utilizes a inside schoolhouse and between year assay to reduce some of this fault. In addition, it is not possible to identify the individual impact of removing chocolate milk on milk sales or milk waste without unrealistically bold that all other effects are either insignificant or abolish each other out. Nonetheless, due to the strong preferences for chocolate milk in schools, information technology may be off-white to assume that student potable selection was minimally influenced by the other menu changes that occurred in the commune. So while the 6.8% decrease in lunch sales is peradventure attributable to eliminating chocolate milk, and is consistent with the theory of reactance (resisting threats to freedom), the decline could also be associated with other factors. [12], [thirteen] Identifying the actual magnitude of this miracle is a promising artery for future research.

This exploratory written report underscores the need for total-scale follow-upwardly studies. In club to more accurately document the increment in waste, before and after measures should be collected. Additionally, the data for this study were collected in unproblematic schools only, were collected for ii months, and were of an aggregate nature. Without specific age categories, and boosted course levels (6–12) the results are express to a small-scale age group. Furthermore, all relationships are correlational because the design is not a randomized controlled blueprint. Moreover, we were not able to divide milk sales into units selected by students taking an NSLP qualifying meal and units purchased by other students. Thus, a properly designed experiment that collects information across ages and for NSLP and non-NSLP participants would be an appropriate follow-up study.

While this exploratory analysis examined the economic-related considerations of eliminating chocolate milk, information technology is also important that future research explore some of the less obvious diet-related trade-offs that might occur. In add-on to examining potential changes in poly peptide, calories, and calcium, it would be important to document whether students compensated at lunch, or after school, past consuming higher calorie beverages or other calorically dense snacks. Though our data did not let u.s. to determine whether students compensated for calories and nutrients when chocolate milk was not available, our estimates of increased milk waste and refuse in cartons selected provide bear witness that students were less satisfied with the set of milk options. Moreover, inquiry suggests that small indulgences can reduce the chances for within-meal calorie bounty. [10] Given this evidence, there is need for additional research to sympathize how behavioral nudges and triggers that preserve options, such equally chocolate milk, and guide students to more healthful choices [17], [22], [23], [24] could lead students to take, and eat, healthier lunches. Later on all, information technology'south not nutrition until it's eaten.

Conclusion

While removing chocolate milk from school cafeterias may appear to have the firsthand do good of reducing calorie and carbohydrate consumption, there might be unexpected consequences to doing so. Our results indicate that when chocolate milk was removed, fewer students took milk, and students wasted more than of the white milk they selected. In add-on, there could besides be consequences to how students compensate during lunch–or later in the mean solar day–such as selecting a dessert. Nutrient service managers need to carefully weigh the costs and benefits of eliminating chocolate milk and should consider other solutions, such every bit making chocolate milk less user-friendly to select and making white milk appear more convenient, attractive, and normal. [25] While at that place are many means to promote white milk selection without restricting available options, the following five suggestions are consistent with previous enquiry conducted in school lunchrooms: 1) keeping all beverage coolers stocked with at least some white milk [23]; 2) white milk representing one/3 or more of all visible milk in the lunchroom [25]; 3) placing white milk in front of other beverages, including chocolate milk, in all coolers [26]; 4) placing white milk crates so that they are the offset beverage selection seen in all milk coolers [22], [27]; and 5) bundling white milk with all grab and go meals available to students equally the default beverage [24].

Encouraging students to take white milk can naturally subtract the amount of chocolate milk taken. While making white milk relatively more user-friendly, bonny, and normal to choose (relative to chocolate milk) will atomic number 82 some children to switch from chocolate to white, it will not influence all children. Notwithstanding, the remaining question is whether or not drinking chocolate milk is better than drinking an alternative caloric potable, such as a sports drink, or even non eating a schoolhouse luncheon at all.

Author Contributions

Conceived and designed the experiments: AH DJ BW. Performed the experiments: AH DJ BW. Analyzed the data: AH DJ BW. Contributed reagents/materials/analysis tools: AH DJ BW. Wrote the newspaper: AH DJ BW.

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