Impact of a "vegetables first" approach to complementary feeding on later intake and liking of vegetables in infants: a study protocol for a randomised controlled trial

Interventions for increasing fruit and vegetable consumption in children aged five years and under

BACKGROUND

Insufficient consumption of fruits and vegetables in childhood increases the risk of future non-communicable diseases, including cardiovascular disease. Testing the effects of interventions designed to increase children's consumption of fruit and vegetables, including those focused on specific child-feeding strategies or broader multicomponent interventions targeting the home or childcare environment, is required to assess the potential to reduce this disease burden.

OBJECTIVES

To assess the benefits and harms of interventions designed to increase the consumption of fruit, vegetables or both amongst children aged five years and under.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase and two clinical trials registries to identify eligible trials on 25 March 2023. We searched Proquest Dissertations and Theses in December 2022. We reviewed reference lists of included trials and contacted authors of the included trials to identify further potentially relevant trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), including cluster-randomised controlled trials (C-RCTs) and cross-over trials, of any intervention primarily targeting consumption of fruit, vegetables or both amongst children aged five years and under compared to no-intervention control, and incorporating a dietary or biochemical assessment of fruit or vegetable consumption. Two review authors independently screened titles and abstracts of identified papers; a third review author resolved disagreements.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the risks of bias of included trials; a third review author resolved disagreements. We used random-effects models in meta-analyses for the primary review outcomes where we identified sufficient trials. We calculated standardised mean differences (SMDs) to account for the heterogeneity of fruit and vegetable consumption measures. We conducted assessments of risks of bias and evaluated the certainty of evidence (GRADE approach) using Cochrane procedures.

MAIN RESULTS

We included 53 trials with 120 trial arms and 12,350 participants. Sixteen trials examined the impact of child-feeding practice interventions only (e.g. repeated food exposure) in increasing child vegetable intake. Twenty trials examined the impact of multicomponent interventions primarily conducted in the childcare setting (e.g. parent nutrition education and preschool policy changes) in increasing child fruit and vegetable intake. Seventeen trials examined the impact of parent nutrition education only in increasing child fruit and vegetable intake. Two trials examined the effect of a nutrition education intervention delivered to children only in increasing child fruit and vegetable intake and one each examined a child-focused mindfulness intervention or providing families with fruit and vegetable interventions. We judged nine of the 53 included trials as free from high risks of bias across all domains. Performance, detection and attrition bias were the most common domains judged at high risk of bias for the remaining trials. There is moderate-certainty evidence that child-feeding practice interventions versus no-intervention control probably have a small positive effect on child vegetable consumption, equivalent to an increase of 15.5 grams as-desired consumption of vegetables (SMD 0.44, 95% confidence interval (CI) 0.24 to 0.65; 15 trials, 1976 participants; mean post-intervention follow-up = 12.3 weeks). No trials in this comparison reported information about intervention costs. One trial reported no harms or serious unintended adverse consequences (low-certainty evidence). Multicomponent interventions versus no-intervention control probably have a small effect on child consumption of fruit and vegetables (SMD 0.27, 95% CI 0.11 to 0.43; 14 trials, 4318 participants; moderate-certainty evidence; mean post-intervention follow-up = 4.0 weeks), equivalent to an increase of 0.34 cups of fruit and vegetables a day. One trial, which tested a multicomponent garden-based intervention, reported the installation of the garden as part of the intervention to be USD 1500 per childcare centre (low-certainty evidence). No trials in this comparison reported information about unintended adverse consequences of interventions. Parent nutrition education interventions may have little to no short-term impact on child consumption of fruit and vegetables versus no-intervention control (SMD 0.10, 95% CI -0.02 to 0.22; 14 trials, 4122 participants; low-certainty evidence; mean post-intervention follow-up = 6.4 weeks). One trial reported the total estimated cost of delivering a parent nutrition education intervention for infant feeding, physical activity and sedentary behaviours delivered by a dietitian as approximately AUD 500 per family (low-certainty evidence). One trial reported no unintended adverse consequences on family food expenditure following implementation of an intervention delivered over the telephone to improve parental knowledge and skills about the home food environment (low-certainty evidence). Trials reported receiving governmental or charitable funds, except for one trial reporting industry funding.

AUTHORS' CONCLUSIONS

There was moderate-certainty evidence that child-feeding practice interventions and multicomponent interventions probably lead to only small increases in fruit and vegetable consumption in children aged five years and under. Parent nutrition education interventions may have little or no effect on increasing fruit and vegetable consumption in children aged five years and under. Future research should be prioritised on assessment and reporting of both intervention cost and adverse effects, and development and evaluation of interventions in research gaps, including in a broader range of settings and in low- and middle-income countries. This review continues to be maintained as a living systematic review with monthly searches for new evidence and incorporation of relevant new evidence as it becomes available. Please refer to the Cochrane Database of Systematic Reviews for the current status of this review.

Nutritional Facts and Health/Nutrition Claims of Commercial Plant-Based Infant Foods: Where Do We Stand?

One of the current drivers of the infant food market is the rising demand for vegan products, and thus accurate knowledge of their nutritional composition is required to guide parents and health professionals. Thus, this study aimed to assess the nutritional composition of commercial plant-based infant foods, in addition to analyzing their health/nutrition claims. A selection of infant products launched in the global market (2017–2021) were classified into eight types and each type was divided into vegan and vegetarian products. Based on the ingredients list, cereals, seeds, pseudocereals and/or pulses were the most used ingredients in the retrieved products. The nutritional composition of six out eight types varied significantly among vegan and vegetarian products. When protein, calcium and iron contents differed significantly, vegan products had the highest protein content in all categories, compared to those that were vegetarian. When significant differences were found in sugar content, vegan products have lower amounts in all categories, compared to vegetarian products. Health and nutrition claims were found mostly used in vegetarian products. Strategies to reduce added sodium and sugar, and saturated fatty acids is required to ensure a healthy diet for infants. This study also implies the importance of a complete labelling of infants’ foods, especially vegan products to help parents making a reasonable choice.

From food preference development to responsive feeding - Selective studies to commemorate the life and work of Dr Leann Birch

Dr Leann Birch was a pioneer in conducting research on infant and child eating behaviour. At the beginning of her research career, Leann recognised a significant gap in the developmental psychology literature, namely that few studies had been conducted to understand infant eating and feeding behaviours. This seems an unusual omission given that food intake is essential and that developmental milestones from milk to solids, and from being fed to becoming an autonomous eater, are obvious to most caregivers. Leann paved the way for interdisciplinary research from psychology, paediatrics and public health to explore and apply this knowledge to infant and child appetite, eating behaviour, dietary patterns, food preferences, and obesity risk. Early studies in her laboratory demonstrated that children form food preferences through experience and socialisation. Experiments published in 1979 tested the role of familiarisation through repeat exposure, and the impact of instrumental and social learning on the acquisition of food preferences. In 1984, a presentation given to the British Feeding and Drinking Group (BFDG) in Brighton set out three organising principles for understanding how children acquire food preferences: genetically pre-programmed behavioural propensities; social constraints on experience with food; and social transmission resulting from direct social interaction. Building on these three organising principles, research on child eating behaviour has flourished, including the intersection between individual differences, food experience and environmental influences on children's food preferences, energy regulation, and weight outcomes. In this review, the initial groundwork set out by Leann Birch on food preference development in children is considered followed by a discussion of how this has since inspired an interdisciplinary, international and expanding field of research on children's food intake, appetite and body weight regulation.

Starting complementary feeding with vegetables only increases vegetable acceptance at 9 months: a randomized controlled trial

BACKGROUND

Starting complementary feeding (CF) with vegetables only may improve vegetable acceptance throughout childhood.

OBJECTIVES

We aimed to test whether exposure to vegetables only during the first 4 wk of CF increases later vegetable acceptance compared with a control group receiving fruit and vegetables.

METHODS

In this randomized, controlled, parallel-group study, 117 Auckland infants received either vegetables only (veg-only, n = 61) or a combination of fruit and vegetables (control, n = 56) for a duration of 4 wk, starting from the first day of CF at ∼4-6 mo of age. The primary outcome measure was intake of target vegetables (broccoli, spinach) provided by the study at 9 mo of age. Daily intake of vegetables (FFQs) at 9 mo was a supporting measure. Infants' iron status (serum ferritin, hemoglobin) was examined at all time points.

RESULTS

The veg-only infants consumed more broccoli and spinach than controls [mean difference (95% CI): 11.83 (0.82, 22.84) g, P = 0.036 and 10.19 (0.50, 19.87) g, P = 0.039, respectively]. Intake of pear was comparable among intervention groups (P = 0.35). At 9 mo, veg-only infants consumed target vegetables at a faster rate [mean difference (95% CI): broccoli, 3.37 (1.26, 5.47), P = 0.002; spinach, 4.12 (0.80, 7.45), P = 0.016] and showed greater acceptance for target vegetables [mean difference (95% CI): broccoli, 0.38 (0.07, 0.70), P = 0.019; spinach, 032 (0.04, 0.60), P = 0.024] than controls. The rate of eating and acceptance of pear was comparable among intervention groups (P = 0.42 and P = 0.98, respectively). Also, veg-only infants consumed more vegetables than controls [86.3 (52.5, 146.3) compared with 67.5 (37.5, 101.3) g, respectively, P = 0.042]. Introducing vegetables as the first food was not associated with 9-mo iron status.

CONCLUSIONS

Providing vegetables as first foods increased vegetable intake at 9 mo of age and may be an effective strategy for improving child vegetable consumption and developing preferences for vegetables in infancy.

Implementing a 'Vegetables First' Approach to Complementary Feeding

Purpose of Review

To provide a rationale for promoting a vegetables first approach to complementary feeding (CF), building on prior exposure to vegetable flavours experienced in utero and via breastfeeding (chemosensory continuity).

Recent Findings

Vegetables confer selective health benefits but population intakes are below recommendations globally; maternal intake of vegetables during both pregnancy and lactation promotes familiarity with some vegetable flavours. Building on this exposure, vegetables as a first food during CF further promote acceptance. However, experiments testing efficacy of a vegetables first approach to CF demonstrate increased liking and intake, some evidence of generalisability but little evidence of sustained effects beyond infancy.

Summary

The aim to increase the quantity and variety of vegetables eaten by children is both desirable, to improve nutrient quality of the diet, and achievable. However, longer, larger, randomised control trials are needed to evidence any longer term, sustainable benefits to liking and intake of vegetables.