Does Eating Vegetables at Start of Meal Prevent Childhood Overweight in Japan? A-CHILD Study

Eating vegetables at school lunchtimes: Pilot and feasibility studies testing strategies to improve intake

Vegetable provision at schools in the UK has increased over recent years; however children still eat few of the vegetables that are served to them. Two experimental pilot and feasibility studies implemented a vegetables-served-first (study 1) plus experiential learning (study 2) approach to increase children's (3-5 years and 4-7 years respectively) vegetable consumption at school lunchtimes. Both studies involved vegetables-served-first 10-min before the rest of the meal, with experiential learning techniques (repeated exposure, "veg-first" dinner plates, vegetable songs, videos, and nutrition education) complementing the vegetable service in study 2. Study 1 (n = 38) found that vegetables-served-first, compared with serving all foods together, increased vegetable intake by ∼12 g. Study 2 (n = 69) found that vegetable consumption depended on individual schools. Schools where vegetable intake was low showed increases in consumption during intervention weeks, whereas schools with high vegetable intake showed little change. Acceptability of interventions was found to be good for children and schools that participated, although concerns about time to serve vegetables first and COVID-related environmental restrictions reduced feasibility for some schools. Child engagement could also be improved by offering a wider variety of vegetables during repeated exposure to reduce monotony. Future research should design interventions using co-design methods including schools to suit their context best, whilst also addressing the problem with a systems approach. Interventions which focus on child learning through experience need to take account of specific school environments including curricular needs, resources available for school lunch (including both time and space), provision of food, support from teachers and parents, and the culture around eating (e.g. encouragement, pressure to eat, lunchtime competing with playtime). Joined-up systems approaches could enhance both provision and uptake of vegetables at school meals.

Impact of COVID-19 pandemic on children overweight in Japan in 2020

OBJECTIVES

This study aimed to explore the association between the coronavirus disease (COVID-19) pandemic and overweight incidence among preadolescent elementary school children in Japan.

METHODS

A population-based longitudinal study was conducted in Adachi City, Tokyo, Japan, using data from the Adachi Child Health Impact of Living Difficulty (A-CHILD) study. The control group (2016-2018) comprised 434 children, and the COVID-19 exposure group (2018-2020) included 3500 children. Overweight was defined as a body mass index (BMI) z-score of 1 SD or more according to the World Health Organization standards. The study design involved comparing BMI z-scores before and after exposure to the pandemic, considering the associated lifestyle changes and potential consequences on physical activity, parental employment status and income.

RESULTS

By 6th grade, the prevalence of overweight increased from 17.7% to 19.2% in the control group and 22.5% to 29.5% in the COVID-19 exposure group. Difference-in-differences analysis revealed that children's exposure to COVID-19 significantly increased BMI z-scores (coefficient 0.22, 95% confidence interval (CI) 0.14-0.29) and a higher odds ratio of overweight (odds ratio 2.51, 95% CI 1.12-5.62), even after adjusting for time-varying covariates.

CONCLUSION

The COVID-19 pandemic has been associated with an increased prevalence of overweight among elementary school children in Japan.

Eating order and childhood obesity among preschoolers in China: A cross-sectional study

Background

Early childhood is a critical period for dietary education and development of good eating habits. However, few studies have investigated the effect of eating order in children and childhood obesity in real-world settings.

Objective

To examine whether the order in which meats/fish or vegetables are consumed affects the risk of obesity in preschoolers.

Methods

We conducted a population-based cross-sectional study using a self-administered online survey on the lifestyle and health behaviors of preschoolers in Taizhou, China. A total of 3,200 parents were invited to take part in the survey, and 2,049 of them completed the questionnaire. Children were classified as having a normal weight, overweight, or obesity using the definitions provided by the International Obesity Task Force, and z-scores for body mass index were calculated. We divided the children's eating order at the beginning of the meal into two groups: "vegetables before meats/fish" or "meats/fish before vegetables". We analyzed the relationship between what was consumed first at a meal and the overweight status of each child.

Results

No difference in body mass index was observed between the children eating meats/fish-first and the children eating vegetables-first during a meal. Children with parents who were affected by obesity were more likely to eat vegetables first. Among children of mothers with obesity, body mass index was significantly higher in the meats/fish-first group than that in the vegetable-first group (2.891 vs. 0.845, P = 0.007). In children whose mothers were affected by obesity, those that ate meats/fish first had a 12.21 times higher risk of being overweight compared with those that ate vegetables first (95% CI:1.22-121.74, P = 0.033).

Conclusion

Our findings suggest eating vegetables or meats/fish at the start of a meal does not affect weight status in preschoolers.

Home Cooking and Child Obesity in Japan: Results from the A-CHILD Study

This study aimed to investigate the association between the frequency of home cooking and obesity among children in Japan. We used cross-sectional data from the Adachi Child Health Impact of Living Difficulty study, a population-based sample targeting all fourth-grade students aged 9 to 10 in Adachi City, Tokyo, Japan. Frequency of home cooking was assessed by a questionnaire for 4258 caregivers and classified as high (almost every day), medium (4-5 days/week), or low (≤3 days/week). School health checkup data on height and weight were used to calculate body mass index z-scores. Overall, 2.4% and 10.8% of children were exposed to low and medium frequencies of home cooking, respectively. After adjusting for confounding factors, children with a low frequency of home cooking were 2.27 times (95% confidence interval: 1.16-4.45) more likely to be obese, compared with those with a high frequency of home cooking. After adjustment for children's obesity-related eating behaviors (frequency of vegetable and breakfast intake and snacking habits) as potential mediating factors, the relative risk ratio of obesity became statistically non-significant (1.90; 95% confidence interval: 0.95-3.82). A low frequency of home cooking is associated with obesity among children in Japan, and this link may be explained by unhealthy eating behaviors.

Association between grandparent co-residence, socioeconomic status and dental caries among early school-aged children in Japan: A population-based prospective study

Globally many children are living with grandparents, and it has been suggested that grandparent co-residence may be associated with dental caries in infants and toddlers possibly through passive parenting style, accompanied by children's cariogenic behaviors such as feeding sugary sweets. However, little is known about this association in schoolchildren, adjusted for socioeconomic status. Therefore, this study investigates the association between grandparent co-residence, socioeconomic status, and dental caries among schoolchildren. All caregivers of first-grade children (age 6-7 years) in Adachi City, Tokyo, were administered a questionnaire about children's grandparent co-residence status and oral health-related behaviors, and responses were linked with dental examination records conducted by school dentists (N = 3,578). Multilevel Poisson regression analysis was applied to examine the association between grandparent co-residence, socioeconomic status, and dental caries status for each individual tooth, adjusting for potential covariates. The percentage of dental caries experience was higher among children living with grandparents (48.9%) than among children living without grandparents (44.0%). The risk for caries, however, did not differ according to grandparent co-residence status when tooth type, child's age and sex, and parental socio-economic status and structure were adjusted (PR, 1.13; 95%CI, 0.90, 1.42). The association between grandparent co-residence and dental caries among early school-aged children in urban Japan was confounded by socioeconomic status.

Association between grandparent coresidence and weight change among first-grade Japanese children

BACKGROUND

The prevalence of grandparent coresidence is increasing. However, the impact of grandparent coresidence on weight change among school-age children remains unclear.

OBJECTIVES

The objective of the study is to examine the association between grandparent coresidence and obesity-related behaviours and change in body mass index (BMI) z scores among school-age children.

METHODS

In total, 3422 caregivers of first-grade children in Adachi City, Tokyo, participated in surveys and health checkups in 2016 and 2017 with no change in their grandparent coresidence status (response rate: 80.1% and 81.4%, respectively). Association between grandparent coresidence and obesogenic dietary, physical activity, and screen-based sedentary behaviours was measured using Poisson regression with robust error variance analysis, while change in BMI z scores was determined by linear regression and adjusting for potential covariates.

RESULTS

Grandparent coresidence was associated with increased prevalence rate (PR) of irregular snack foods intake (PR: 1.38, 95% confidential interval (CI): 1.19, 1.61); however, children who live with grandparents showed a lower BMI z scores in the second grade (coefficient: -0.048, 95% CI: -0.094 to -0.0013) after adjustment for BMI z scores in the first grade, family sociodemographics, and obesogenic behaviours.

CONCLUSION

Grandparent coresidence is associated with lower BMI z scores among early primary school-age Japanese children living in urban areas.

Association between social capital and second dose of measles vaccination in Japan: Results from the A-CHILD study

BACKGROUND AND OBJECTIVES

Measles vaccination is important to prevent outbreak, and social capital can be an important preventive factor. However, there have been very few studies that investigated the association between social capital and measles vaccination, especially the second dose, which is more likely to be suboptimal. This study aimed to investigate the association between social capital and second dose of measles vaccine.

METHODS

Data were derived from a population-based study of first-grade elementary school children (6-7 years old) in Adachi City, Tokyo. Caregivers were asked to complete a questionnaire, and 4291 of them provided a valid response (response rate: 80.1%). Among these 4291 valid responses, 69 responses were excluded since variables for social capital measures were missing, which resulted in analytic sample size of 4222. We analyzed the association between measles vaccination and social capital including social ties, social trust and mutual aid by multilevel logistic regression analysis with a random intercept model.

RESULTS

About 8.9% of the children did not receive a second dose of measles-containing vaccines. After covariates adjustments, increase of one-standard-deviation of poor individual-level social ties showed 11% lower odds of receiving measles-containing vaccines (OR: 0.89, 95% CI: 0.80-0.99). By contrast, no significant association between community-level social ties and measles vaccination was found. Regarding social trust, no significant association between individual-level social trust and measles vaccination was found. However, increase of one-standard-deviation of poor community-level social trust showed 11% lower odds of receiving measles-containing vaccines (OR: 0.89, 95% CI: 0.79-0.998). There was no association between mutual aid and measles vaccination.

CONCLUSION

Social ties and social trust were associated with second dose of measles vaccination. Fostering social capital may be effective in raising the low rate of second dose of measles vaccine.