Feasibility and reliability of digital imaging for estimating food selection and consumption from students’ packed lunches

Accuracy of Reporting Food Intakes among Primary School Children Aged 7-9 Years

BACKGROUND

Accurate measurement of dietary intake throughout childhood is important to monitor children's growth and development and for their long-term health. However, measuring dietary intake in children is challenging because of misreporting, difficulties in establishing portion size, and heavy reliance on proxy reporters.

OBJECTIVES

This study aimed to determine the accuracy of self-reported food intake by primary school children aged 7-9 y.

METHODS

A total of 105 children (51% boys), aged 8.0 ± 0.8 y, were recruited from three primary schools in Selangor, Malaysia. Individual meal intakes during a school break time were determined using a food photography method as the reference method. The children were then interviewed the following day to assess their recall of their meal intakes the previous day. ANOVA and Kruskal-Wallis tests were used to determine mean differences in the accuracy of reporting food items and amount by age and weight status, respectively.

RESULTS

On average, the children achieved 85.8% match rate, 14.2% omission rate, and 3.2% intrusion rate for accuracy in reporting food items. The children also achieved 85.9% correspondence rate and 6.8% inflation ratio for accuracy in reporting food amounts. Children living with obesity had notably higher intrusion rates compared with normal weight children (10.6% vs. 1.9%) (P < 0.05). Children aged >9 y had notably higher correspondence rates, compared with children aged 7 y (93.3% vs. 78.8%) (P < 0.05).

CONCLUSIONS

The low omission and intrusion rates and the high correspondence rate indicate that primary school children aged 7-9 y are capable of self-reporting food intake accurately for a lunch meal without proxy assistance. However, to confirm children's abilities to report their daily food intakes, further studies should be conducted to assess the accuracy of children in reporting their food intakes for more than one meal in a day.

Food Photography as a Tool to Assess Type, Quantity, and Quality of Foods in Parent-Packed Lunches for Preschoolers

OBJECTIVE

Explore using food photography to assess packed lunches in a university-based Early Childhood Center and contextualize these photographs through parent interviews.

METHODS

An explanatory sequential design was used. Packed lunches were photographed to assess the type and quantity of foods offered and consumed by Child and Adult Food Care Program components (fruit, vegetable, grain, and protein) and quality of foods offered using the Healthy Meal Index. Parent interviews aimed to understand motivations and behaviors related to packing lunch.

RESULTS

Data were collected on 401 lunches. Only 16.2% of lunches met all Child and Adult Food Care Program requirements. Most lunches included fruit (84%) and grains (82%), whereas fewer included vegetables (44%). Portion sizes were large, especially for grains (2.7 ± 1.5 servings). In interviews (n = 24), parents expressed tension between offering healthful items and foods they knew their child would eat, as well as concern about children going hungry.

CONCLUSIONS AND IMPLICATIONS

Food photography is a feasible methodology to capture parent-packed lunches for preschoolers and may have utility in nutrition education, particularly related to age-appropriate portion sizes.

Processed and Packed: How Refined Are the Foods That Children Bring to School for Snack and Lunch?

BACKGROUND

Increasing consumption of highly processed foods has been associated with adverse health outcomes among children. In the US, children consume up to half of their daily energy intake at school.

OBJECTIVES

We sought to characterize foods that children bring from home to school according to processing level and to evaluate the effectiveness of a school-based intervention, Great Taste Less Waste (GTLW), in reducing the proportion of energy brought from highly processed foods from home compared with control.

DESIGN

Secondary data analysis of a 7-month school-based, cluster-randomized trial.

PARTICIPANTS/SETTING

Third- and fourth-grade students (n = 502, mean age: 9.0 ± 0.62 years) at 10 public elementary schools in Eastern Massachusetts (school year 2012-2013).

INTERVENTION

GTLW included a 22-lesson classroom curriculum, homework activities, monthly parent newsletters, a food shopping and packing guide for parents, food demonstrations, school-wide announcements, and a poster contest.

MAIN OUTCOME MEASURES

The energy content of foods brought to school was estimated from digital photographs, and foods were assigned to 1 of 3 processing levels (less processed or unprocessed, moderately processed, or highly processed) based on an established classification system.

STATISTICAL ANALYSES PERFORMED

The percentage of energy brought from foods categorized into each processing level was calculated and compared pre- and postintervention using hierarchical linear models.

RESULTS

Most of the food brought from home to school was highly processed (70% of food energy brought). Foods categorized as snack foods and desserts contributed the greatest percentage of total energy to the highly processed category at baseline and follow-up (72% and 69%, respectively). Energy from foods brought for snack tended to be more highly processed than those brought for lunch. No significant differences were observed from pre- to postintervention in the GTLW group compared with control for the percentage of energy brought from highly processed foods in adjusted models (β: -1.1, standard error: 2.2, P = .6) or any other processing level.

CONCLUSIONS

Highly processed foods were prevalent in home-packed lunches and snacks, and these patterns persisted after a targeted intervention. Further research is needed to identify strategies to improve the healthfulness of foods brought from home to school.

Measuring Food Waste and Consumption by Children Using Photography

A photography method was used to measure waste on food trays in school lunch in France, using the 5-point quarter-waste scale. While food waste has been studied extensively in US school lunches, the structure of the French lunch meal is quite different, with multiple courses, and vegetables (raw and cooked) in more than one course. Vegetables were the most wasted food category as usually seen in school lunch research, especially cooked vegetables, which were wasted at rates of 66%-83%. Raw vegetables were still wasted more than main dishes, starchy products, dairy, fruit, and desserts. Vegetables were also the most disliked food category, with the classes of vegetables falling in the same order as for waste. Waste and liking were highly correlated. Sensory characteristics of the food were cited as a main reason for liking/disliking. There is a strong connection between food liking and food consumption, and this connection should be the basis for future attempts to modify school lunch to improve consumption. The photographic method of measuring food waste at an individual level performed well.

Comparisons of school and home-packed lunches for fruit and vegetable dietary behaviours among school-aged youths

OBJECTIVE

School-based interventions and policies encourage youths to include and consume fruits and vegetables at lunchtime via school lunches, but limited research has examined how these behaviours compare when youths have home-packed lunches. The objective of the present study was to compare fruit and vegetable contents and consumption among students having school or home-packed lunches over the school week.

DESIGN

Participants were observed over five consecutive days at school lunchtime. Trained analysts estimated students' lunchtime fruit and vegetable contents and consumption using digital imaging. Mixed models examined associations between fruit and vegetable dietary behaviours and lunch source (school v. home-packed), controlling for student gender, grade and school.

SETTING

Three elementary schools in northern California, USA.ParticipantsFourth-, fifth- and sixth-grade students (nchildren 315; nobservations 1421).

RESULTS

Students were significantly less likely to have and to consume fruits and vegetables (all P&lt;0·05) when having home-packed lunches, compared with when having school lunches. Among those who did have or did consume these foods, having a home-packed lunch was associated with consuming significantly less fruit (P&lt;0·05) but no differences for other dietary outcomes.

CONCLUSIONS

The study adds to a growing body of literature indicating shortfalls in fruit and vegetable contents and consumption associated with having a home-packed lunch, relative to having a school lunch. Findings suggest that school-based interventions, particularly when targeting home-packed lunches, should focus on whether or not these foods are included and consumed, with less emphasis on quantities.

Parental and family predictors of fruits and vegetables in elementary school children's home-packed lunches across a school week

Home-packed lunches have been found to be of lower nutritional quality than school-bought lunches, yet little is known about family-based factors associated with lunch packing. The current exploratory study examines parental and family predictors of fruits and vegetables packed in lunches, hypothesizing parents' nutrition knowledge and authoritative parenting as well as children's involvement in lunch decisions would relate to packing more fruits and vegetables, while financial difficulties would relate to packing fewer. Ninety parent-child dyads from 4th-6th grade participated for 5 consecutive school days. Lunch contents were recorded using a digital imaging procedure to capture the number of days a fruit or vegetable was packed, and servings of fruits and vegetables in lunches each day. Parents completed family and parenting questionnaires and daily reports of child involvement in lunch decisions. Count-based regression models and longitudinal analyses within a multilevel modeling framework were used to examine predictors of lunch contents. Higher nutrition knowledge was associated with packing more fruit across the week and more vegetables on Monday. Authoritative parenting was associated with packing fewer vegetables on Monday, but more servings across the week. Financial stress was related to higher rates of never packing vegetables and when vegetables were packed including fewer servings, while child involvement in lunch decisions was associated with packing more fruits across the week, packing vegetables on more days and more servings of vegetables on Monday. Findings suggest parental and family factors impact the foods in packed lunches, with implications for children's dietary intake at school. Outreach programs can help parents pack more fruits and vegetables by providing nutrition education and suggestions for affordable, healthy lunch options as well as encouraging child involvement in the lunch packing process.