Introduction
Health benefits of high fruit and vegetable intakes
Consideration of fruits and vegetables as different food groups
Vegetable-specific consumption
Health benefits of high vegetable-specific intakes
Determinants of vegetable-specific consumption
Strategies to increase vegetable-specific consumption: systematic review
Method
Results
Interventions aiming to change or use hedonic factors
Reference/intervention | Aim | Intervention | Comparison | Results | Conclusions |
---|---|---|---|---|---|
Bouhlal et al. [121] Taste | To increase V intakes in children aged 18–37 months (n = 74) | 1. Reduction in salt provision (0 %) 2. Increase in salt provision (1.2 %) | Usual salt provision (0.6 %) | Less V consumed in I1 vs C. No effects for I2 | Salt addition should be limited, but its suppression in V, whose intake is to be promoted, should be considered cautiously |
Bouhlal et al. [121] Taste | To increase V intakes in children aged 18–37 months (n = 74) | 1. Reduction in fat provision (0 %) 2. Increase in fat provision (5 %) | Usual fat provision (2.5 %) | No differences between conditions | Fat addition could be avoided in foods for children without having an impact on palatability |
Savage et al. [122] Study 1 Taste | To increase willingness to taste, liking and consumption of V in children aged 3–5 years (n = 34) | Single exposure to 3 target V paired with: 1. Plain reduced-fat dip 2. Favoured flavoured reduced-fat dip | Single exposure to 3 target V paired with no dip | Increased willingness to taste in I vs C. No differences between I1 and I2 | Offering V with reduced-fat dips containing familiar flavours can increase tasting and thereby promote liking, acceptance and consumption of V, including V previously rejected or disliked |
Savage et al. [122] Study 2 Taste | To increase willingness to taste, liking and consumption of V in children aged 3–5 years (n = 26/27) | Single exposure to 2 target unfamiliar or disliked V (celery, squash) with a favoured flavoured reduced-fat dip | Single exposure to 2 target V with no dip | Increased intakes in I vs C | Offering V with reduced-fat dips containing familiar flavours can increase tasting and thereby promote liking, acceptance and consumption of V, including V previously rejected or disliked |
Bouhlal et al. [123] Taste | To increase V intakes in children aged 8–11 years (n = 75) | 1. Reduction in salt provision (0 %) 2. Increase in salt provision (1.2 %) | Usual salt provision (0.6 %) | Less V consumed in I1 vs C. No effects for I2 | Salt content has a positive and food-specific effect on intake |
Morizet et al. [124] Familiarity | To increase V dish selection in 8–11 year olds. School-based intervention | Novel V dishes with no label (carrots n = 60, broccoli n = 65) | Familiar V dishes with no label | Increased selection for C vs I | Adding a label with the V name can increase children’s willingness to select a novel V dish instead of a familiar one. Familiar V are otherwise more likely to be consumed |
Ahearn [125] Taste | To increase V consumption in a 14 year old boy with autism. Case study | Simultaneous presentation of 3 V with liked condiments | No control | I significantly increased intakes | Adding condiments increased food acceptance across three food items |
Reference/intervention | Aim | Intervention | Comparison | Results | Conclusions |
---|---|---|---|---|---|
Remy et al. [126] Exposure Conditioning | To increase V acceptance at complementary feeding (children aged 4–8 months) | 1. RE—10 exposures to target V puree (n = 32) 2. FFL—10 exposures to target V puree paired with sweetener (n = 32) 3. FNL—10 exposures to target V puree paired with energy (n = 31) | Control V—limited experimental exposures | No differences in intake in I vs C postintervention. Intake of target V puree increased postintervention and at 3-m follow-up in I1 and I2, but not I3 vs pretest. Liking increased only in I1. No effects at 6-m follow-up | RE is as effective as and simpler to implement than FFL and more effective than FNL for increasing V acceptance at complementary feeding |
Mennella et al. [127] Study 2 Exposure | To increase V acceptance in infants aged 4–9 months | 1. 8-day exposure to single V (n = 11) 2. 8-day exposure to several V in different meals (n = 12) 3. 8-day exposure to several V in the same meals (n = 12) | No control (pre-post comparison only) | Increased intakes of green beans, carrots and spinach in I3 compared to before. Trend towards increased intakes of green beans in I1 and I2 after intervention vs before | Repeated opportunities to taste a particular or a variety of foods may promote willingness to eat V |
Mennella et al. [128] Exposure | To increase V acceptance in infants aged 6–11 months | Milk formula flavoured with hydrolysate (similar taste to target V) (n = 24) | Milk formula (no hydrolysate taste) (n = 50) | Less target V (and relative to other V) was consumed by I vs C | Taste preferences are initially specific to the context they are learnt (in this case milk) |
Hetherington et al. [129] Exposure | To increase liking and acceptance of target V and unfamiliar V during weaning (children aged 6–12 months) | 12 daily exposures to target V puree added to milk, then 12 × twice daily exposures to target V puree added to baby rice (n = 18) | Plain milk for 12 days, then plain rice for 12 days (n = 18) | Intake, liking and eating pace were greater for target V but not unfamiliar V for I vs C, at end of intervention No differences at 6 or 18-m follow-up | Early exposure to vegetables in a step-by-step method could be included in complimentary feeding guidelines to enhance V intakes |
Maier et al. [130] Exposure | To increase V acceptance in children aged 7 months (n = 49) | 1. 8 daily exposures to disliked V 2. 8 daily exposures to liked V | No control (pre-post comparison only) | Intakes increased in I1 and I2, greater increases for I1. Effects sustained for 9 months (self-report) | When a V is initially disliked it is worth persisting in feeding (exposure) for at least 8 subsequent meals |
Caton et al. [131] Exposure Conditioning | To increase V acceptance in children aged 9–38 months | 1. RE—10 exposures to target V puree (n = 22) 2. FFL—10 exposures to target V puree paired with sweetener (n = 25) 3. FNL—10 exposures to target V puree paired with energy (n = 25) | Control V—limited experimental exposures | Greater intake in I vs C, postintervention and 5-w follow-up. No differences between interventions postintervention. Higher intakes in I1 vs I2 at 5-w follow-up | RE, FFL and FNL were effective for increasing V acceptance, and equally so |
Barends et al. [120] Exposure | To increase V intakes in children aged 12–23 months | Started weaning with target V (green beans/artichoke), exclusive V for 18 days, 9 exposures to target V (n = 51) | Starting weaning with fruit, exclusive fruit for 18 days, 9 exposures to target fruit (n = 50) | Greater liking and intake of green beans, and greater intake of novel V, postintervention in I vs C, but no effects for artichoke | Weaning with V but not with fruits, may promote V acceptance in children |
Barends et al. [132] | Follow-up of Barends et al. [120] | As above | As above | Greater reported liking and daily intake of V at 12 months in I vs C, but no differences at 23 months. No differences in measured intake at either time point | Weaning exclusively with V results in a higher daily V consumption until at least 12 months of age |
Ahern et al. [133] Exposure Conditioning | To increase V acceptance in children aged 12–60 months (n = 29) | 1. RE—8 exposures to target V puree 2. FFL—8 exposures to target V puree paired with apple puree for sweetness | Control V—0 exposures | Significant increases in V intake from pre- to postintervention. No differences between conditions | No effects of exposure The addition of a familiar flavour (FFL learning) confers no advantage above exposure |
Hausner et al. [134] Exposure Conditioning | To increase V acceptance in children aged 22–38 months | 1. RE—10 exposures to target V puree (n = 32) 2. FFL—10 exposures to target V puree paired with sweetener (n = 33) 3. FNL—10 exposures to target V puree paired with energy (n = 39) | Control V—limited experimental exposures | Greater intake in I1 and I2 vs pretest, at postintervention, 3-m and 6-m follow-up. No effects in I3. No comparison with C | RE and FFL were effective for increasing V acceptance, and equally so. FNL was not effective |
Bouhlal et al. [135] Exposure Conditioning | To increase V acceptance in children aged 2–3 years | 1. RE—8 exposures to target V puree (n = 47) 2. FFL—8 exposures to target V puree paired with salt (n = 54) 3. FFL—8 exposures to target V puree paired with spice (n = 50) | Control V—no exposures | Greater intake in all I vs pretest, at postintervention, 1-, 3- and 6-m follow-up. Greater effects in I1 vs I2 and I3. Increases in liking also in I1 and I2. No change in C, but no statistical comparison with I provided | RE appears to be the simplest choice to increase V intake in the short and long term in toddlers |
De Wild et al. [136] Conditioning | To increase preferences and intake for target V in children aged 2–4 years (n = 28) | Seven twice weekly consumptions of target V soup (endive/spinach) paired with high energy | Seven twice weekly consumptions of target V soup (spinach/endive) paired with low energy | Increased preferences for I vs C immediately after intervention, no effects on intake. No effects at 2 and 6-month follow-up. Increase in intake for all V from pre- to postintervention | Results show an effect of exposure on intake, but not conditioning. Effects of conditioning are found in preferences |
Holley et al. [137] Exposure Conditioning Modelling | To increase acceptance of a disliked V in children aged 2–4 years | 1. Exposure—daily exposure to target V for 14 days (n = 29) 2. Exposure + modelling—parent also consumed target V and gave positive comment for 14 days (n = 27) 3. Exposure + rewards—child given praise and non-food reward for tasting target V for 14 days (n = 29) 4. Exposure, modelling + rewards—all above strategies for 14 days (n = 27) | No exposure or other intervention | No differences between I and C when all groups analysed together. Significant increases in V intake and liking in I3 and I4 vs C in secondary analyses | Parent-led interventions based around modelling and offering incentives may present cost-efficient ways to increase children’s V consumption |
Wardle et al. [75] Exposure | To increase liking and intake for a previously disliked V in children aged 2–6 years. Home-based intervention | Exposure—child given a daily taste of V for 14 days (n = 50) | No intervention (wait list) (n = 45) | Greater increases in liking, ranking and consumption of V from pre- to postintervention in I vs C | A parent-led, exposure-based intervention involving daily tasting of a V holds promise for improving children’s acceptance of and increasing liking for a previously disliked V |
Fildes et al. [138] Exposure Rewards | To increase V acceptance in children aged 3 years. Mailed intervention | Mailed instructions to offer children 14 daily tastes of a disliked V and sticker reward (n = 196) | No intervention (usual practice) (n = 246) | Intake and liking of V increased in I vs C. Acceptability of the protocol was also very high among I parents | Mailed instructions for taste exposure were effective in increasing children’s acceptance of an initially disliked vegetable |
Anzman-Frasca et al. [139] Study 1 Exposure Conditioning | To increase V liking and intakes in children aged 3–6 years (n = 41) | 1. RE—twice weekly exposures to initially not-liked V for four weeks 2. AC—twice weekly exposures to initially not-liked V with a liked dip for four weeks | No exposure | Liking increased in I1 and I2, vs C, but no differences between I1 and I2 | Administering few small tastes of V that are initially not liked, both with and without dip, can have a lasting impact on liking and intake of those V |
Anzman-Frasca et al. [139] Study 2 Conditioning | To increase V liking and intakes in children aged 3–6 years (n = 43) | AC—twice weekly exposures to initially not-liked V with a liked dip for four weeks | RE—twice weekly exposures to initially not-liked V for four weeks | Liking increased in I and C, but no differences between them | Administering few small tastes of V that are initially not liked, both with and without dip, can have a lasting impact on liking and intake of those V |
O’Connell et al. [140] Exposure | To increase V intakes in children aged 3–6 years old | 10 exposures of 3 different V at lunch over 30 days (30 exposures) (n = 50) | No exposure (n = 50) | No differences between conditions | Research should explore the conditions necessary for exposure to increase V intakes in preschool settings |
Correia et al. [141] Conditioning | To increase V intakes and willingness to try in pre-school children (3–5 years) | Lunch Target V paired with familiar well-liked food (n = 43) | Lunch Target V not paired with familiar well-liked food | No differences in intakes. Willingness to try increased marginally in I vs C | Further research should explore the strategy of pairing vegetables with liked foods |
Fisher et al. [142] Conditioning | To increase liking and intakes in bitter-sensitive and insensitive preschoolers | 13 exposures to moderately liked V over 7 weeks with: 1. regular salad dressing as dip (n = 39) 2. light salad dressing as dip (n = 36) 3. regular dressing as sauce (n = 38) | 13 exposures to moderately liked V over 7 weeks with: no dressing (n = 39) | No effects on intake in insensitive children. Higher liking and intakes in bitter-sensitive children in all I vs C. Effects vary based on whether regular or light dressing was provided as a dip or sauce | Offering dips can promote vegetable intake among some children who are sensitive to bitter tastes |
Havermans and Jansen [143] Conditioning | To increase liking and preference for a target V taste in children aged 4–6 years (n = 13) | 6 conditioning trials—V juice paired with sweet taste | 6 trials—different V juice not paired with sweet taste | Increase in liking and preference for I vs C | Flavour-flavour learning may be beneficial in increasing children’s liking and acceptance of vegetables |
Hendy et al. [144] Rewards | To increase (fruit and) V intakes in 1st, 2nd and 4th graders. School-based intervention | Rewards given for consumption of V at 12 meals (n = 96) | Rewards given for consumption of fruit at 12 meals (n = 96) | Increased intakes of V following I vs C. Increased preferences for V (marginal) after intervention vs before | The use of rewards as in the Kids Choice programme shows promise as a simple and effective method to increase children’s (fruit and) V acceptance |
Cooke et al. [145] Exposure Rewards | To increase V likings and intakes in children aged 4–6 years | Twelve daily taste exposures to target (disliked) V with 1. tangible reward (n = 99) 2. social reward (n = 106) 3. no reward (exposure only) (n = 105) | No exposure (n = 112) | Liking increased in I1, I2, and I3 vs C, postintervention and 1- and 3-m follow-up. No differences between interventions. Consumption increased in I1 and I2 vs C postintervention and 1- and 3-m follow-up. Consumption increased in I3 vs C postintervention and 1-m follow-up only | Rewarding children for tasting an initially disliked V produced sustained increases in acceptance, with no negative effects on liking |
Corsini et al. [146] Exposure Rewards | To increase liking and consumption of a disliked V in children aged 4–6 years | 1. EO—Daily exposure for 2 weeks (n = 62) 2. ER—Daily exposure, plus sticker reward, for 2 weeks (n = 60) | No exposure (n = 66) | Increased liking at postintervention in I1 and I2 vs C, and no further change over 4-w and 3-m follow-ups. Target V consumption increased postintervention in all groups, and continued to increase for I2 at 4w and 3 m, and for C at 3 m | The findings support the effectiveness of using a reward with a repeated exposure strategy. In particular, such rewards can facilitate the tastings necessary to change liking |
Noradilah et al. [147] Exposure | To increase acceptance of a target disliked V in children aged 5–6 years (n = 42) | Target V served at lunch on 3 consecutive days | No control | Increased intakes of V in I from day 1 to 3. Parent reported child liking of V also increased | Multiple exposures to V could be a strategy to increase consumption of V among children |
Wardle et al. [148] Exposure Rewards | To increase V acceptance in children aged 5–7 years | 1. Exposure—8 daily offers to taste and eat target disliked V (n = 15) 2. Reward—8 daily offers to taste, eat and gain reward sticker for target disliked V (n = 16) | No exposure or reward (n = 18) | Increased liking and consumption in I1 vs C. Intermediate effects in I2. Increased intakes in all groups after intervention vs before | Repeated exposure to the taste of unfamiliar V is a promising strategy for promoting liking of previously disliked V in children |
Lakkakula et al. [149] Exposure | To increase liking for target V in fourth/fifth grade children (n = 360). Part of a wider school-based intervention | Offered cold carrots, tomatoes and bell peppers, and hot peas to taste once a week for 10 weeks | No control | For children who began the programme disliking the target V, I improved liking scores for carrots, tomatoes and peas; liking for bell peppers did not change. For children who began the study liking the target V, no changes were found | Repeated tasting of less-liked vegetables by children in a cafeteria-based setting is a strategy to promote liking of these items, that is effective in approximately half of the participants |
Johnston et al. [150] Conditioning | To increase V consumption and V variety in 6th grade children | V paired with a preferred taste (peanut butter) weekly for 4 months (n = 40) | V exposure weekly for 4 months (n = 38) | Significant increases in vegetable consumption, and variety of vegetables eaten in I vs C | Pairing of vegetables with a preferred taste may be an effective technique for increasing consumption |
Zeinstra et al. [151] Conditioning | To increase V preferences and consumption in children aged 7–8 years (n = 19) | Seven daily exposures to V juice paired with high energy | Seven daily exposures to V juice paired with low energy | No differences between I and C, but consumption was very low | The pure taste of vegetables is not acceptable enough to allow adequate consumption for flavour-nutrient conditioning to occur |
Olsen et al. [152] Exposure Conditioning | To increase V intakes in children aged 9–11 years | 1. Neutral V paired with liked V for 6 exposures, followed by 6 exposures to 3 V (n = 72) 2. Neutral V alone for 6 exposures, followed by 6 exposures to 3 V (n = 74) 3. Neutral V paired with disliked V for 6 exposures followed by 6 exposures to 3 V (n = 73) | No exposure | Increases in neutral V intake between I1 vs I2 and I1 vs I3. No other differences. No differences between conditions in liking | Pairing with a liked V increased neutral V consumption. Serving V that are mixed in this manner has potential for increasing intakes |
Reference/intervention | Aim | Intervention | Comparison | Results | Conclusions |
---|---|---|---|---|---|
Heath et al. [153] Exposure via picture books | To increase familiarity and liking for V in 20- to 24-month-old children | Reading a picture book every day for 2 weeks including: 1. a liked V (n = 19) 2. a disliked V (n = 19) 3. an unfamiliar V (n = 19) | Test procedures conducted on target V and control (non-exposed) V | Increased intakes, and reduced encouragement to try unfamiliar V in all I, and particularly I3 vs C. No effects in willingness to taste | Results confirm the potential for picture books to play a positive role in encouraging healthy eating in young children |
Bryne and Nitzke [154] Exposure via picture books | To improve attitudes and behaviours towards an unfamiliar V in children aged 3–5 years | 1. Childrens book with positive messages about V (kohlrabi) 2. Childrens book with negative messages about V (kohlrabi) (n = 118) | No book | More V tasters in I1 vs C during the second posttest | Children’s books with positive messages can increase willingness to taste |
De Droog et al. [155] Exposure via picture books Social activities | To increase carrot consumption in children aged 4–6 years | 5 days exposure to 1. Picture book containing carrots and rabbit, passive reading (n = 26) 2. Picture book containing carrots and rabbit, active reading (n = 26) 3. Picture book containing carrots and turtle, passive reading (n = 26) 4. Picture book containing carrots and turtle, active reading (n = 26) | No exposure to book (n = 56) | More carrots consumed in all I vs C. Greater consumption with active v passive reading | Young children seem to enjoy this interactive shared reading, triggering positive feelings that increase children’s liking and consumption of the food promoted in the book |
Interventions based on changing the environment
Reference/intervention | Aim | Intervention | Comparison | Results | Conclusions |
---|---|---|---|---|---|
Coulthard et al. [156] Variety | To increase V intakes in children aged 4–6 months | Exposure to a variety of V over 9 days | Exposure to 1 V over 9 days | Those weaned later (5–6 m) in I consumed significantly more novel V vs C. No effects in those weaned earlier (4–5 m) | Infants who are weaned at 6 m may benefit from being weaned onto a variety of tastes |
Maier et al. [157] Variety | To increase novel V acceptance in children aged 7 months | Phase 1 1. 3 daily exposures to 3 V (n = 46) 2. 3 alternated daily exposures to 3 V (n = 51) Phase 2 All groups given 5 alternate exposures to 2 V | Phase 1 9 daily exposures to 1 V (n = 51) Phase 2 5 alternate exposures to 2 V | Intakes and liking of novel V after phase 1 and phase 2 increased in I1 and I2 vs C, greater increases for I2 | High variety produced greatest new food intake |
De Wild et al. [158] Variety | To increase V intakes in children aged 2–5 years. Home-based intervention | Exposure over 12 meals to 2 target V simultaneously (n = 34) | Exposure over 12 meals to 1 target V (n = 36) | I positively associated with higher intake than C but not significantly so | Choice-offering has some, but not a robust effect on increasing V intake in children |
Spill et al. [159] Availability | To increase V consumption (and decrease energy intake) in children aged 3–5 years (n = 51) | Lunch starter provided of: 1. 30 g carrots 2. 60 g carrots 3. 90 g carrots | No lunch starter | Greater target V and total V consumption in all I vs C, and in I2 and I3 vs I1. No differences in total energy intake | Increasing the portion size of a V served as a first course can be an effective strategy for increasing V intakes in preschool children |
Spill et al. [160] Availability | To increase V intakes in children aged 3–5 years (n = 72) | Lunch starter provided of: 1. 150 g tomato soup 2. 225 g tomato soup 3. 300 g tomato soup | No soup served | Greater intakes of V in I1, I2 and I3 vs C. Increasing the soup portion size increased soup and V intake | Serving low-energy-dense V soup as a first course is an effective strategy to increase V consumption at the meal |
Spill et al. [161] Availability | To increase V (and reduce energy) intakes in children aged 3–5 years (n = 40) | 1. Pureed V (triple content) added to foods across 1 day to reduce energy density by 85 % 2. Pureed V (quadruple content) added to foods across 1 day to reduce energy density by 75 % | Energy density—100 % | V intake increased in I1 and I2 vs C. No compensatory effects on V side dish consumption | The incorporation of substantial amounts of puréed V is an effective strategy to increase daily V intake and decrease energy intake in young children |
Correia et al. [141] Presentation | To increase V intakes and willingness to try in preschool children (3–5 years) | Snack: Target V arranged in appealing manner (n = 42) | Snack: Target V not arranged in appealing manner | No effects of I | Further research should explore the strategy of pairing vegetables with liked foods, no effects of appearance |
Mathias et al. [162] Availability | Intervention to increase V intakes in children aged 4–6 years | Serving of 150 g V at a single meal | Serving of 75 g V at a single meal | Increased V intake in I vs C. Effects limited to those who liked V | Serving larger V portions at meals can be used to promote young children’s intake of V without influencing fruit or total energy intake |
Bucher et al. [163] Variety | To increase V intakes in children aged 7–10 years | Selection from buffet (fake foods) of pasta, chicken and 2 V (carrots, beans) (n = 34) | Selection from buffet containing pasta, chicken and 1 V (carrots (n = 32) or beans (n = 34)) | Children served themselves more energy from V in I vs C. No differences in total meal energy | Variety is effective in increasing the V choice of school-aged children. Serving an assortment of V in school cafeterias might be a simple and effective strategy to improve children’s nutrition |
Morizet et al. [124] Presentation | To increase vegetable dish selection in 8- to 11-year-olds. School-based intervention | Novel V dishes with: 2. basic label (carrots n = 44, broccoli n = 72) 3. model-related label (carrots n = 41, broccoli n = 90) | Novel V dishes with no label | Increased intakes in I2 and I3 vs C [I reverses reduced selection for no label (I1, see Table 1)], and no differences between I2 and I3 | Adding a label with the V name can increase children’s willingness to select a new V dish instead of a familiar one |
Wansink et al. [164] Study 1 Presentation | To increase V selection in children aged 8–11 years old. School-based intervention | 1. V served at lunch with attractive label (n = 32) 2. V served at lunch with generic label (n = 38) | V served at lunch with no label (n = 45) | Increased intakes of V in I1 vs I2 and C. No effects on selection | Attractive names effectively and persistently increased healthy food consumption in elementary schools |
Wansink et al. [164] Study 2 Presentation | To increase V selection in children aged 8–11 years old. School-based intervention | V served with attractive name every day for 1 month (n = 742) | V served with no name every day for 1 month (n = 810) | Increased selection of V in I vs C | Attractive names effectively and persistently increased healthy food consumption in elementary schools |
Just and Wansink [165] Availability | To increase V selection in a school canteen | Introduction of a salad bar | No salad bar | Increase in number of children consuming salad in I vs C | Simple changes can increase selection |
Just and Wansink [165] Variety | To increase V intakes in a school canteen | Giving students a choice of 1 of 2 V | No choice—requiring students to take 1 V | Increased intakes of V in I vs C | Providing choice within forced selection improved intakes |
Just and Wansink [165] Location | To increase V selection in a school canteen | Salad bar positioned, so that children must walk round it | Salad bar positioned, to the side | Immediate increase in sales of salad following I vs C. Continued to increase | Simple changes can increase selection |
Redden et al. [166] Study 1 Availability Serving order | To increase V intakes in 5th grade children | Mildly liked V provided in isolation while waiting for lunch (n = 755). V also provided for lunch | V only provided for lunch (n = 680) | Increased total V consumption in I vs C | Intervention increased target V consumption |
Redden et al. [166] Study 2 Availability Serving order | To increase V intakes in 5th grade children | Mildly liked V provided in isolation while waiting for lunch (n = 486–530). V and control V also provided for lunch | V and control V only provided for lunch (n = 529–558) | Increased mildly liked V intake and total intake in I vs C. No change in control V consumption. Sustained effects over 3 days | Intervention increased target V consumption, and did not decrease other V consumption |
Reicks et al. [167] Presentation | To increase V intakes in elementary school children (kindergarten—5th grade) (n = approx.. 800) | Photographs of target V (carrots, green beans) were placed in lunch trays at one lunch | No photographs, same lunch served | Increased selection of V in I vs C, so increased consumption. Students selecting beans consumed the same in I and C, but students selecting carrots also consumed more in I vs C | Placing photographs in cafeteria lunch trays incurs minimal costs, but was associated with an increase in V consumption within the range of those found in more expensive interventions |
Bucher et al. [168] Variety | To enhance V choices and improve meal composition in college students | Buffet meal (fake food) of pasta, chicken and 2 V (carrots, beans) (n = 34) | Buffet meal (fake food) of pasta, chicken and 1 V (carrots (n = 29) or beans (n = 35)) | Participants in I chose more energy and more % energy from V vs C. No differences in total energy selected | Serving an assortment of V might be a simple and effective strategy to increase V intakes and improve meal composition |
Blatt et al. [169] Availability | To increase V (and reduce energy) intakes in adults (n = 41) | 1. Pureed V (triple content) added to foods across 1 day to reduce energy density by 85 % 2. Pureed V (4.5 times content) added to foods across 1 day to reduce energy density by 75 % | Energy density—100 % | V intake increased and energy density decreased in I1 and 2 vs C | Large amounts of puréed V can be incorporated into foods to increase V intakes and reduce energy intakes |
Meengs et al. [170] Variety | To promote V intakes in adults (n = 66) | 1 meal involving 200 g each of 3 V | Three meals involving 600 g of 1 V (same three V) | Increased V intake at I vs C. Increased V intake at I vs most preferred C | Increasing the variety of V served at a meal can be used to increase V intake |
Redden et al. [166] Study 3 Serving order | To increase V intakes in adults | Mildly liked V provided in advance of other more liked foods (n = 36) | Other foods provided: 1. in advance of V (n = 43) 2. simultaneously (n = 39) | More V consumed in I vs C1 and C2 | Eating V first in isolation may prove useful for increasing V consumption in a wide range of individuals |
Rolls et al. [171] Availability | To increase V intakes (and facilitate weight management) in adults | Addition Study (n = 49) 1. 270 g V served 2. 360 g V served Other meal components unchanged Substitution Study (n = 48) 1. 270 g V served 2. 360 g V served Other meal components reduced proportionally | Addition Study 180 g V served Other meal components served Substitution Study 180 g V served Other meal components served | Greater V served led to greater V consumed in both studies Effects on meal energy density and energy intake also in the substitution study | Serving more V, either by adding more or substituting them for other foods, is an effective strategy to increase V intake at a meal |
Shenoy et al. [172] Availability | To increase V intakes (and improve CVD health) in healthy adults | Education on the DASH diet and: 1. 8 oz V juice daily (n = 30) 2. 16 oz V juice daily (n = 30) | Education on the DASH diet only (n = 30) | I1 and I2 increased V intakes (and improved micronutrient profiles) vs C (and decreased blood pressure in prehypertensive adults) | Including 1–2 cups of vegetable juice daily was an effective and acceptable way for healthy adults to consume more V |
Shenoy et al. [173] Availability | To increase V intakes (and improve CVD health) in adults with metabolic syndrome | Education on the DASH diet and: 1. 8 oz V juice daily (n = 27) 2. 16 oz V juice daily (n = 27) | Education on the DASH diet only (n = 27) | I1 and I2 increased V intakes vs C (and decreased blood pressure. No effects on CVD measures) | Including 1–2 cups of vegetable juice daily was an effective and acceptable way for healthy adults to consume more V |
Interventions based on changing or using cognitive factors
Reference/intervention | Aim | Intervention | Comparison | Results | Conclusions |
---|---|---|---|---|---|
Wardle et al. [75] Education | To increase liking and intake for a previously disliked V in children aged 2–6 years. Home-based intervention | Information—nutritional advice and leaflet (n = 48) | No intervention (wait-list) (n = 45) | No differences between I and C | A parent-led, exposure-based intervention involving daily tasting of a V holds promise for improving children’s acceptance of to increasing liking for a previously disliked V. No effects for information only |
Zeinstra et al. [174] Choice | Intervention to increase V intakes in children aged 4–6 years. Single restaurant meal intervention | 1. Pre-meal choice—Single choice at the start of the meal of 1 of 2 V (n = 110) 2. At-meal choice—Repeated choices throughout the meal of 2 V (n = 97) | No choice—provision of 1 of 2 V (n = 96) | No differences in V liking or intake between conditions. Some effects of individual differences | Having a pre-meal choice was appreciated by the children but did not affect intake, liking, or motivation to eat vegetables |
Dominguez et al. [175] Choice | Intervention to increase V intakes in children aged 4–6 years | 1. Single choice at the start of the meal of choice of 2 V (n = 50) 2. Repeated choices throughout the meal of choice of 2 V (n = 56) | No choice—provision of 2 V (n = 44) | Total V intakes were higher in I1 and I2 vs C | Results demonstrate the enhancing effect of providing choice to increase V intakes in young children |
Gholami et al. [176] Skills-based education | To increase V provision and consumption in 6–11 year old children | Theory based instructional leaflets to promote self-regulatory skills for providing healthy nutrition for children | No intervention (usual practice) | Increased V intake in I vs C, 2 weeks postintervention. No difference 3 months postintervention | Engaging mothers in self-regulatory health promotion programmes may facilitate more vegetable intake among their daughters |
Morris and Zidenberg-Cherr [177] Education Exposure Experience | To increase V intakes in 9–10 year olds (4th grade). School-based intervention | 1.NL—nutrition education (n = 71 in school 1) 2. NG—nutrition education plus gardening activities (6 V planted) (n = 81 in school 2) | No formal nutrition or gardening education (n = 61 in school 3) | Knowledge and preferences for 2 V, increased, in I1 and I2 vs C, postintervention, and remained for 1 V per I at 6 months. Preferences for 1 V and 1 additional (non-planted) V increased in I2 vs I1 and C, postintervention and at 6 months. No differences in willingness to taste V | Garden-enhanced nutrition education is an effective tool for improving nutritional knowledge and V preferences |
Morgan et al. [178] Education Experience | To increase V intakes, V preferences and FV knowledge in 11- to 12-year-olds. School-based intervention | 1. NE—10 week nutrition education (n = 35) 2. NEG—10 week nutrition education and garden (n = 35) | No intervention (wait list) (n = 57) | Greater willingness to taste V and greater taste ratings for I1 and I2 vs C. No differences in V intakes | School gardens can impact positively on willingness to taste V and V ratings, but more comprehensive strategies are required to increase V intakes |
Robinson et al. [179] Study 3 Memory | To increase V intakes in university students | Recall positive V memory | Recall of other memories | Increased V intake in I vs C | Recall of previous eating experiences could be a potential strategy for altering food choices |
Stok et al. [180] Study 1 Education | To increase V intakes in university students | Descriptive social norm—majority norm | Descriptive social norm—minority norm | Marginally significant increase in V intakes in I vs C | A norm describing the behaviour of a salient social group can impact on behaviour |
Ogawa et al. [181] Education | To increase V purchasing behaviour in adults | Point of purchase (POP) health information for V presented in supermarket store for 60 days | Control store (same supermarket chain)—no information | Increased sales at I vs C. Adjustments made for seasonal effects and number of customers | Health-related POP information for V in supermarkets can encourage customers to purchase V |
Rahman et al. [182] Education | To increase dark leafy green vegetable (DLGV) presentation to children aged 6–35 months by mothers | 1. health education, plus feeding demonstration (n = 44) 2. health education only (n = 36) | No intervention (usual practice) (n = 80) | Increased number of mothers presented DLGV at an impromptu meal 8 weeks later in I1 and 2 vs C Maternal literacy and family income controlled for | Education for mothers was effective at increasing DLGV intakes in children |
Tabak et al. [183] Education | To increase presentation of V by mothers, and V intakes in children aged 2–5 years | Parents sent 4 tailored newsletters and given 2 motivational phone calls over 4 months (n = 22) | Parents sent 4 children’s books (1/month) (n = 21) | Increased availability and offering of V in I vs C. No differences in intakes | Home-based interventions to alter parental feeding practices and the home environment may help towards increasing V intake in children |
Wenrich et al. [105] Skills-based education | To increase serving and consumption of deep-orange, cruciferous and DGLV in families | 8 weekly interactive sessions for food preparers, including recipes and handouts | 8 weekly mailings that included similar recipes and handouts | No differences in servings or intakes between I vs C, at end of intervention or three-month follow-up. More recipe use by I vs C | Tools to help the food preparer draw family members into recipe evaluation are useful |
Clarke et al. [184] Education | To increase V intakes in clients of community pantries | 1. Tailored tips and recipes (n = 244) 2. Generic tips and recipes (n = 226) | No tips or recipes (n = 236) | Increased V use in I1 vs I2 and C | Results demonstrated benefits of tailoring over both generic and control conditions |
Multi-component interventions
Reference/intervention | Aim | Intervention | Comparison | Results | Authors’ conclusions |
---|---|---|---|---|---|
Faber et al. [185] Education Availability Exposure Experience | To improve intakes of yellow and dark green leafy V (DGLV) in children aged 2–5 years. A rural home gardening intervention | Home gardening programme in a rural village, as part of a primary care activity (n = 126 home gardens, 1/3 households) | Neighbouring village with no home gardening programme | At 20-month follow-up, children from I consumed yellow and DGLV more often vs C. Maternal knowledge also improved in I | A home gardening programme that was integrated with a primary health care activity, linked to nutrition education, and focused on the production of yellow and DGLV improved the vitamin A status of 2- to 5-y-old children in a rural village in South Africa |
Bai et al. [186] Education Exposure Rewards Experience | To increase attitudes, intentions and V consumption. School-based intervention in children in US third grade | Nutrition education, poster displays, featured V in canteen (1/month for 9 months), and daily V tasting (4 preparations) (n = 38) | No intervention (usual practice) (n = 35) | Self-report V intakes higher in I vs C. Attitudes predicted consumption in I, social norms predicted consumption in C. Schools matched for race and gender profiles | The Veggiecation programme generated a positive attitude to influence vegetable intake in school |
Leak et al. [187] (protocol only) | To increase V intake, liking and variety in children aged 9–12 years. Intervention for caregivers | Intervention based on 9 behavioural economics strategies for 6 weeks (n = 36) | Usual practice for 6 weeks (n = 10) | Protocol only | Protocol only |
Wright et al. [188] Education Exposure Experience | To increase V selection at a salad bar in kindergarten—5th grade children. School-based intervention | Gardening programme for three weeks, including V growing, tasting and consuming, and increasing knowledge | No control | V selection increased during I and continued to rise post I to a lesser extent | Gardening intervention lessons and activities impacted on V intakes |
Ratcliffe et al. [189] Education Experience | To increase V intakes in children aged 11–13 years. School-based intervention | Health and science education. Garden based education (n = 170, 2 schools) | Health and science education only (n = 150) | Increased self-report recognition of, attitudes towards, preferences for, willingness to taste, and V variety consumed in I vs C. No differences in taste test | Gardening improved recognition of, attitudes towards, preferences for, willingness to taste and variety of V eaten |
Brown et al. [97] Education Exposure Experience | To increase readiness to change, V self-efficacy and V intakes in college students. College based intervention (n = 186) | Online preparation videos and tasting of 4 V, one per month for 4 months (n = 186) | No control | Stage of change and V self-efficacy increased postintervention. Intakes for one V increased, but no effects for other V or all V | Online V demonstration videos may be an effective and cost-efficient intervention for increasing self-efficacy of V preparation and readiness to increase V consumption among college students |
Carney et al. [190] Education Experience Social activities | To increase V intakes (reduce food security and improve family relationships) in families | Community gardening programme, including education, gardening experiences, and social activities (n = 42 families, 163 individuals) | No control | I increased V intakes (reduced food insecurity and improved family relationships) from pre- to postintervention | A community gardening programme can increase V intakes, reduce food insecurity and improve family relationships |
Schreinemachers et al. [191] Availability Education Experience | To increase V production, consumption and dietary diversity in families | Garden training, education, seeds, cooking, and garden equipment (n = 103) | No intervention (wait-list) (n = 479) | I resulted in increased V production, consumption and dietary variety vs C | Women’s home gardens are an effective intervention for increasing supply and consumption of a range of V in poor households, and so contributing to nutrition security |
Kushida and Murayama [192] Availability Education | To increase V consumption behaviours in adults in workplace cafeterias | 12 informational table tents placed every 2 weeks on all cafeteria tables, posters and locally grown V included in cafeteria menu. Personal dietary feedback for all participants (n = 181) | No intervention, Personal dietary feedback for all participants (n = 168) | Increased V consumption in I vs C in the cafeteria, and across the day (self-report) | Findings suggest a beneficial effect of providing access to nutrition information about V consumption |
Weatherly and Weatherly [193] Availability Education Experience | To increase V consumption (and increased interaction and self-worth) in homebound adults | Container V garden | No control | Reports of improved interaction and self-worth. Participants received fresh produce, but no results provided for V consumption | The containerised V garden programme has many benefits, for homebound adults and volunteer helpers |