Nutritional labelling for healthier food or non‐alcoholic drink purchasing and consumption

Rachel A Crockett<sup>a</sup>; Sarah E King; Theresa M Marteau; A T Prevost; Giacomo Bignardi; Nia W Roberts; Brendon Stubbs; Gareth J Hollands<sup>a</sup>; Susan A Jebb

doi:10.1002/14651858.CD009315.pub2

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Figure 1

Examples of nutritional labels used in practice

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Figure 2

Logic model of the process by which nutritional labelling may have an impact on diets and health

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Figure 3

Study flow diagram

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Figure 4

Risk of bias summary

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Figure 5

Forest plot of comparison: Labelling on menus vs no labelling in restaurants, and energy (kcal) of food purchased

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Figure 6

Forest plot of comparison: Labelling on menus or placed on a range of food options vs. no labelling in laboratory settings, and energy (kcal) consumed

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Analysis 1.1

Comparison 1: Labelling on menus vs no labelling in restaurants, Outcome 1: Energy (kcal) of food purchased

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Analysis 2.1

Comparison 2: Labelling on menus or placed on a range of food options vs no labelling in laboratory settings, Outcome 1: Energy (kcal) consumed during a meal

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Analysis 3.1

Comparison 3: Labelling on menus vs no labelling in laboratory settings (studies with a low risk of bias), Outcome 1: Energy (kcal) consumed during a meal

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Analysis 4.1

Comparison 4: Labelling of a single food or drink option vs no labelling in laboratory settings, Outcome 1: Energy (kcal) consumption

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Analysis 5.1

Comparison 5: Labelling of a single food or drink option vs no labelling in laboratory settings (studies at low risk of bias), Outcome 1: Energy (kcal) consumption

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Analysis 6.1

Comparison 6: Consumption in laboratory settings: subgroup analysis by dietary restraint (studies providing a range of food options), Outcome 1: Energy (kcal) consumed during a meal

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Analysis 7.1

Comparison 7: Consumption in laboratory settings: subgroup analysis by dietary restraint (study providing a single food option), Outcome 1: Energy (kcal) consumed during a snack

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Analysis 8.1

Comparison 8: Consumption in laboratory settings: subgroup analysis by study country (studies providing a range of food options), Outcome 1: Energy (kcal) consumed during a snack/meal

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Analysis 9.1

Comparison 9: Consumption in laboratory settings: subgroup analysis by study country (studies providing single food option), Outcome 1: Energy (kcal) consumed during a snack/meal

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Analysis 10.1

Comparison 10: Low fat (or energy) labelling vs no labelling on high‐energy foods, Outcome 1: Energy (kcal) consumed during a snack/meal in laboratory settings

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Summary of findings 1. Summary of findings table

Outcomes	*Anticipated absolute effects (95% CI)**		Relative effect (95% CI)	№ of participants (studies)	Quality of the evidence (GRADE)	Comments
Nutritional labelling compared to no labelling for healthier food purchasing and consumption
Patient or population: university students/staff and general consumers Setting: real‐world and laboratory settings Intervention: nutritional labelling Comparison: no labelling
Outcomes	Risk with no labelling	Risk with nutritional labelling	Relative effect (95% CI)	№ of participants (studies)	Quality of the evidence (GRADE)	Comments
Food purchased from vending machines assessed with: diet soda beverages/week Follow‐up: 5 weeks ^a	Although more beverages were purchased in the labelling group, large baseline imbalances arising from a small number of randomised units meant that an accurate effect size could not be calculated.		—	(1 RCT)	⊕⊝⊝⊝ Very low^b	Sample size unknown (population purchasing from 3 intervention and 2 control public vending machines)
Food purchased from a grocery store assessed with: calorie‐healthy foods as % of sales Follow‐up: 94 months	Sales performance decreased after labelling was introduced in this interrupted time series study, although this was difficult to interpret because results were measured as health foods as a proportion of overall foods, rather than directly measuring the number of products purchased.		—	(1 ITS study)	⊕⊝⊝⊝ Very low^c	Sample size unknown (population purchasing from a large chain of grocery stores)
Food purchased in restaurants (labels on menus) assessed with: kcal Follow‐up: range 2 weeks to 19 weeks	The median food purchased in restaurants was 746 kcal^d	MD 46.72 kcal fewer (78.35 fewer to 15.10 fewer)^e	—	1877 (3 RCTs)	⊕⊕⊝⊝ Low^f	Six additional studies (one Q‐RCT and 5 ITS studies which took place in a restaurant, cafeterias or coffee shops) also measured purchasing, 2 of which were ITS studies at low risk of bias (which assessed energy labels on menus/menu boards in a coffee shop or cafeteria) and found results consistent with this meta‐analysis.
Food consumed in laboratory settings (labels on menus or labels placed on a range of food options) assessed with: kcal	The median food consumed in laboratory settings was 796.4 kcal^d	MD 50.27 kcal fewer (104.41 fewer to 3.88 more)	—	1705 (8 RCTs)	⊕⊕⊝⊝ Low^g	—
Food consumed in laboratory settings (single snack food or drink option) assessed with: kcal	The median food consumed in laboratory settings was 316.975 kcal^d	SMD 0.05 (95% CI −0.17 to 0.27), P = 0.67	—	732 (6 RCTs)	⊕⊕⊝⊝ Low^h	An SMD of 0.05 represents a small effect (Cohen 1988).
Potential harms (high‐energy snack foods consumed with misleading low fat/energy labels in laboratory settings) assessed with: kcal	The median food consumed with misleading low fat/energy labels in laboratory settings was 190 kcal^d	SMD of 0.19 (95% CI −0.14to 0.51), P = 0.25	—	831 (5 RCTs)	⊕⊝⊝⊝ Very lowⁱ	An SMD of 0.19 represents a small effect (Cohen 1988).
*The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval; RR: risk ratio; OR: odds ratio.
GRADE Working Group grades of evidence High quality: we are very confident that the true effect lies close to that of the estimate of the effect Moderate quality: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different Low quality: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect Very low quality: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect
^aAll outcomes measuring immediate purchasing or consumption decisions at the point of exposure to the label, although returning customers in non‐laboratory settings may have experienced repeat exposure during the study period. ^bDowngraded by two levels for very serious risk of bias and one level for a high degree of imprecision given no useful effect estimate could be calculated. ^cRating begins at 'low' as this is an observational study. Downgraded by one level for serious risk of bias, and one level for indirectness, as outcome was measured as a proportion of overall purchasing rather than directly measured. ^dMedian value among the control groups in the included studies. ^e Assuming this result applied consistently to a population average meal of 600 kcal, this would represent a reduction of 7.8% (95% CI 2.5% to 13.1%). ^f Downgraded by two levels for very serious risk of bias. ^g Downgraded by one level for imprecision, as the 95% confidence interval included the possibility of no effect and of a meaningful decrease, and by one level for indirectness, as behaviour observed in a laboratory setting may not be applicable to real‐world settings. Although five of the included studies were at unclear risk of bias, we did not downgrade for risk of bias. ^hDowngraded by one level for serious risk of bias and one level for indirectness, as behaviour observed in a laboratory setting may not be applicable to real‐world settings. ⁱDowngraded one level for serious risk of bias, one level for heterogeneity, one level for indirectness (as behaviour observed in a laboratory setting may not be applicable to real‐world settings) and one level for imprecision (as the 95% confidence interval included the possibility of a meaningful decrease or increase).

Summary of findings 1. Summary of findings table

Reference and study design	Participants and setting	Intervention/comparison (sample sizes)	Outcome	Results	Summary effect
Allan 2015 Q‐RCT	Coffee shop customers at academic hospital Real‐world setting	Energy content of all food and drinks available on point of purchase signs vs. no information (N = 20,516 items purchased)	Proportion of high energy food and drinks purchased (as a percentage of total drinks and snacks sold)	The proportion of high energy snacks purchased was 41% in the intervention and 45% the control group (P = 0.04); the proportion of high energy drinks purchased was 46% in the intervention group and 50% in the control group (P = 0.15).	Effect size and confidence intervals could not be calculated.
Bollinger 2011 Interrupted time series	Coffee shop customers Real‐world setting	Energy content on menu and menu boards vs no information (N = 118,480 transactions reported)	Mean kcal of food and drinks purchased per transaction	"Estimates of the effect of calorie posting (calories per transaction): log (beverages and food) = −0.060 (0.001)^a–representing a ... decrease in average calories per transaction, equivalent to 14.4 calories"	Regression P value < 0.01
Chu 2009 Interrupted time series	Customers at a university dining centre Real‐world setting	Nutrition facts information on menu board (N = 14,199 entrées sold) vs no label (pre‐intervention: N = 13,951 entrées sold; post‐intervention N = 14,020 entrées sold)	Mean kcal content of entrées purchased per day	Mean energy content of entrées sold at start of the pre‐intervention period: 646.5 kcal with a slope of 0.094 kcal per day. The difference in energy content of entrées sold between the pre‐treatment last day and treatment first day was −12.4 kcal (P = 0.007). Following this reduction, the difference in slope pre‐intervention to intervention was −0.298 kcal per day, and the difference in slope intervention to post‐intervention was 1.512 kcal per day. This means that the average energy content of entrées purchased reduced immediately after the intervention, and gradually increased when the intervention was removed.	Regression P values were 0.56 (pre‐intervention to intervention slope), and 0.013 (intervention to post‐intervention slope).
Cioffi 2015 Interrupted time series	Customers at a university dining centre Real‐world setting	Nutrition facts label on pre‐packaged meals and snacks vs no label (sample sizes not reported)	Mean kcal purchased per week from meals and snacks	"Mean [energy] purchased decreased significantly across the 3 [time points] of the pre‐labelling period. However, no such trend was observed in the post‐labelling period." (data compared over 3 time points)."After labelling, the mean energy content of the items purchased per week decreased significantly from 476.2 (SD 8.7) kcals to 445.3 (SD 8.1) kcals per week (p<0.001)."	A statistical comparison of time trends (i.e. slope) before and after the intervention was not reported, so that the overall effectiveness of the intervention is not clear.
Dubbert 1984 Interrupted time series	Customers at a public cafeteria Real‐world setting	'Lower calorie' label on green paper with a red dot on right‐hand corner beside food item vs no label (sample sizes of foods purchased is not clear)	Probability of choosing low energy entrées, vegetables, or salads	"The probability of choosing a low [energy] entrée did not differ from baseline." The probability of purchasing lower‐energy vegetables and salads significantly increased compared to the no label baseline conditions (P < 0.001).	A statistical comparison of time trends before and after the intervention was not clearly reported, so that the overall effectiveness of the intervention is not clear.
Ellison 2013 RCT	Customers at a restaurant Real‐world setting	1. Energy content on menu (n = 54) 2. Menu with energy content using traffic light format (n = 54) 3. No label (n = 30)	Mean kcal purchased per meal (including entrées, desserts and drinks)	756.5 kcal (SD 338.5)^b vs 765 kcal (SD 368.0)	MD −8.50 kcal (95% CI −154.85 to 137.85)
Ellison 2014a RCT	Customers at a restaurant Real‐world setting	1. Energy content on menu (n = 469) 2. Menu with energy content using traffic light format (n = 591) 3. No label (n = 472)	Mean kcal purchased per meal (entrées only)	705.6 kcal (SD 334.7)^c vs. 746 kcal (SD 368.0)	MD −40.38 kcal (95% CI −79.21 to −1.55)
Holmes 2013 Interrupted time series	Families at a restaurant Real‐world setting	Children's menu with energy and fat content label vs no label (N = 1275 meals)^d	Mean kcal purchased per meal	"The calorie and fat menu had the biggest change in calories compared to the control menu (−9.54), but it was not significant."	A statistical comparison of time trends before and after the intervention was not reported, so that the overall effectiveness of the intervention is not clear.
VanEpps 2016 RCT	Employees at large company buying lunch online Real‐world setting	1. Energy content on menu (n = 38) 2. Menu with energy content using traffic light format (n = 46) 3. No label (n = 123)^e	Mean kcal purchased per meal	537.9 kcal (SD 203.9)^f vs. 605.3 kcal (SD 222.5)	MD −67.38 kcal (95% CI −126.09 to −8.66)
^aAccounting for effects of week, day of week and weather. ^bSDs were calculated from P values reported in the text; means and SDs for both intervention groups were combined (intervention 1: 817 kcal (SD 334.6); intervention 2: 696 kcal (SD 334.6)). ^cSDs were based on Ellison 2013; means and SDs for both intervention groups were combined (intervention 1: 719 kcal (SD 334.6); intervention 2: 695 kcal (SD 334.6)). ^dThe authors also evaluated two other labelling interventions (a healthy (apple) symbol, and a 'Nutrition Bargain Price') that were not eligible for inclusion in this review. ^eThe authors also evaluated one other labelling interventions (traffic light labels without energy information) that was not eligible for inclusion in this review. ^fMeans and SDs (obtained from the study authors) for both intervention groups were combined (intervention 1: 543.8 (SD 180); intervention 2: 533.1 (SD 223.6)).

Reference and study design	Participants and setting	Intervention/comparison (sample sizes)	Outcome	Results	Summary effect
Labelling on menus or placed on a range of food options on energy consumed during a meal
Girz 2012 ‐ study 2 RCT	University students Experimental (laboratory) study at a university	Energy content on menu plus information on recommended daily energy intake for women and men (n = 60) vs no label (n = 66)^a	Mean kcal consumed during a meal (salad and pasta)	608.2 kcal (SD 350.8)^b vs 631.3 kcal (SD 324.0)	MD −23.02 kcal (95% CI −141.28 to 95.24)
Girz ongoing RCT	University students Experimental (laboratory) study at a university	Energy content on menu (n = 24) vs no label (n = 25)	Mean kcal consumed during a meal	433.1 kcal (SD 260.2) vs 426.5 kcal (SD 237.4)^c	MD 6.60 kcal (95% CI −133.02 to 146.22)
Hammond 2013 RCT	Adults Experimental (laboratory) study at a university	1. Energy content on menu (n = 165) 2. Menu with energy content using a traffic light format (n = 156) 3. Menu with energy, fat, salt, and sugar content using traffic light format (n = 152) vs no label (n = 162)	Mean kcal consumed during a fast food meal	761.6 kcal (SD 348.9)^d vs 839.6 kcal (SD 318.8)	MD −78.00 kcal (95% CI −136.29 to −19.70)
Harnack 2008a RCT	Adolescents and adults Experimental study conducted in hotel conference rooms/church hall	Energy content on menu plus information on recommended daily energy intake for women and men (n = 151) vs no label (n = 150)^e	Mean kcal consumed during a fast food meal	804.7 kcal (SD 423.9) vs 739.0 kcal (SD 358.2)	MD 65.70 kcal (95% CI −22.94 to 154.34)
James 2015 RCT	Adults, including university students Experimental study at a university	Energy content on menu plus information on recommended daily energy intake for women and men (n = 99) vs no label (n = 99)^f	Mean kcal consumed during a meal	722.0 kcal (SD 271.6)^g vs 770.0 (SD 269.1)	MD −48.00 kcal (95% CI −123.31 to 27.31)
Platkin 2014 RCT	Female university students Experimental (laboratory) study at a university	1. Energy content on menu (n = 20) 2. Menu with energy content and exercise equivalents (n = 20) vs no label (n = 22)	Mean kcal consumed during a fast food meal	870.1 kcal (SD 375.9)^h vs 995.4 (SD 429.4)	MD −125.33 kcal (95% CI −339.26 to 88.59)
Roberto 2010 RCT	Adults from the community Experimental (classroom) study at a university	1. Energy content on menu (n = 92) 2. Menu with energy content plus information on recommended daily intake (n = 103) vs no label (n = 92)	Mean kcal consumed during a meal	1293.3 kcal (SD 656.8)ⁱ vs 1458.9 kcal (SD 724.6)	MD −165.58 kcal (95% CI −340.01 to 8.84)
Temple 2010 RCT	Adults Experimental (laboratory) study at a university	Nutrition facts label on foods (n = 23) vs no label (n = 24)	Mean kcal consumed during a meal	620.4 kcal (SD 203.6) vs 822.8 kcal (SD 408.7)^j	MD −202.40 kcal (SD −385.86 to −18.94)
Labelling of a single food or drink option on energy consumed during a snack or meal
Cavanagh 2014 RCT	Female university students Experimental (laboratory) study at a university	Energy label on chocolate cookie (130 kcal) (n = 62) vs no label (n = 62)^k	Mean grams consumed from snack of chocolate chip cookies	45.1 g (SD 21.50) vs 33.1 g (SD 21.57)^l	SMD 0.55 (95% CI 0.19 to 0.91)
Crockett 2014 RCT	Adults Experimental study at a cinema	Red 'high fat' label on side of popcorn container (n = 96) vs no label (n = 88)^m	Mean kcal consumed from snack of toffee or salted popcorn (high‐fat snack)	413.5 kcal (SD 307.6)ⁿ vs 468.1 kcal (SD 361.9)	SMD −0.16 (95% CI −0.45 to 0.13)
Ebneter 2013 RCT	Female university students Experimental study at a university	Energy label ('new colours of regular M&M's, 240 calories per serving"') on glass container containing M&M's (n = 41) vs no energy content label ('new colours of regular M&M's') (n = 38)^o	Mean kcal consumed during snack of M&M's (high‐fat snack)	157.2 kcal (SD 98.5) vs165.9 kcal (SD 141.5)	SMD −0.07 (95% CI −0.51 to 0.37)
Kral 2002 Q‐RCT	Females Experimental (laboratory) study at a university	Energy label plus 'colour‐coded' information on level of energy density on an entrée (n = 20) vs no label (n = 20)	Mean kcal consumed from an entrée at breakfast, lunch and dinner	1534.0 kcal (SD 451.7) vs 1569.0 kcal (SD 335.4)	SMD −0.09 (95% CI −0.71 to 0.53)
Roberto 2012 RCT	Adults Experimental (laboratory) study at a university	1. Smart choices label on cereal box (n = 76 analysed) 2. Modified smart choices label (n = 71) vs no label (n = 69)	Mean grams of high‐sugar breakfast cereal and milk consumed	225.7 g (SD 138.2)^p vs 219.9 g (SD 127.1)	SMD 0.04 (95% CI −0.24 to 0.33)
Vermeer 2011 Q‐RCT	Adults Experimental study at a cinema	Portion size and energy content label (display board) (n = 48) vs no label (n = 41)	Mean millilitres of soft drink consumed	376.3 mL (SD 125.4) vs 382.14 mL (SD 147.6)^q	SMD −0.04 (95% CI−0.46 to 0.37)
^aTwo other interventions were combined by the study authors as a 'calorie only' intervention (400 kcal salad and 1200 kcal pasta, and 1200 kcal salad and 400 kcal pasta (although both salad and pasta contained 1200 kcal)). We did not include this data in the above analysis as it involved mislabelling some of the foods (data were not reported separately for consumption of foods that were accurately labelled). ^bMeans and SDs were reported separately for men and women by the study authors; we have combined these data. ^cData were obtained from the study authors (Girz ongoing). ^dMean and SDs for all three intervention groups were combined (intervention 1: 744.2 kcal (SD 368.1); intervention 2: 776.8 kcal (SD 350.9); intervention 3: 764.9 (SD 326.2)). ^eThe authors also evaluated other labelling interventions (energy information and daily recommended intake plus price modification, and price modification alone) that were not eligible for inclusion in this review. ^fThe authors also evaluated another intervention (exercise label describing the number of minutes of brisk walking required to burn the energy for each food item), but as this intervention did not present energy content information, it was not eligible for inclusion in this review. ^gSDs were calculated from confidence intervals. ^hSDs were calculated from standard errors. Means and SDs for both intervention groups were combined (intervention 1: 898.82 kcal (SD 392); intervention 2: 841.31 kcal (SD 82.07)). ⁱMeans and SDs for both intervention groups were combined (intervention 1: 1334.72 kcal (SD 621); intervention 2: 1256.37 kcal (SD 689)). ^jData were obtained from the study authors (Temple 2010). ^kThe authors also evaluated another labelling intervention (high energy label on a low energy cookie) that was not eligible for inclusion in this review. ^lThese data were converted kcal using formula presented in DeGroot 2012. ^mThe authors also evaluated another labelling intervention (green 'low fat' label on high fat popcorn) that is not reported here (see Table 5). ⁿMeans and SDs for two types of popcorn (toffee and salted), reported separately in the paper, were combined. ^oThe authors also evaluated two other labelling interventions (low fat label with and without energy information on high fat snacks) that is not reported here (see Table 5). ^pMeans and SDs for both intervention groups were combined (intervention 1: 219.21 (SD 133); intervention 2: 232.61 (SD 144)). These data were then converted kcal using formula presented in DeGroot 2012. ^qThese data were converted kcal using formula presented in DeGroot 2012.

Reference and study design	Participants and setting	Intervention/comparison (sample sizes)	Outcome	Results	Summary effect
Crockett 2014 RCT	Adults Experimental study at a cinema	Green 'low fat' label on side of container containing high‐fat popcorn (n = 103) vs no label (n = 88)	Mean kcal consumed from snack of popcorn	402.44 kcal (SD 288.68) vs 468.07 kcal (SD 361.93)	SMD −0.20 (95% CI −0.48 to 0.08)
Ebneter 2013 RCT	Female university students Experimental study at a university	Low fat label ('new low fat M&M's') on glass container containing M&M's (n = 49) vs no energy information label ('new colours of regular M&M's') (n = 38)	Mean kcal consumed during snack of M&M's	192.34 kcal (SD 145.53) vs165.88 kcal (SD 141.5)	SMD 0.18 (95% CI−0.25 to 0.61)
Girz 2012 ‐ study 1 RCT	Female university students Experimental (laboratory) study at a university	Lower energy label (600 kcal) on high‐energy salad and pasta (actually 1200 kcal) (n = 56) vs no label (n = 49)^a	Mean kcal consumed during a meal (salad and pasta)	400.26 kcal (SD 199.8) vs 420.19 kcal (SD 233.69)	SMD −0.09 (95% CI −0.47 to 0.29)
Wansink 2006 ‐ study 1 Q‐RCT	Students and their families Experimental study at a university	Low fat label ('new low fat M&M's') on glass container containing M&M's vs no energy information label ('new colours of regular M&M's') (n = 269 overall (n by group not reported))	Mean kcal consumed from snack of M&M's	Mean 244 kcal (SD not reported) vs 190 kcal (SD not reported)	SMD 0.44 (95% CI 0.20 to 0.68)^b
Wansink 2006 ‐ study 3 Q‐RCT	University staff, graduates and undergraduates Experimental study at a university	Low fat label ('Low‐Fat Rocky Mountain Granola') on zip lock bag vs no label ('Regular Rocky Mountain Granola') (n = 66 overall (n by group not reported))	Mean kcal consumed from snack of granola	Mean 249 kcal (SD not reported) vs 165 kcal (SD not reported)	SMD 0.69 (95% CI 0.20 to 1.18)^c
^aData were extracted for those who chose pasta or salad when it was inaccurately as '600 calories'. ^bSMD was calculated based on F‐test data reported in the text. ^cSMD was calculated based on F‐test data reported in the text.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1.1 Energy (kcal) of food purchased Show forest plot	3	1877	Mean Difference (IV, Random, 95% CI)	‐46.72 [‐78.35, ‐15.10]

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