Monetary value of self-reported diets and associations with sociodemographic characteristics and dietary intake among Japanese adults: analysis of nationally representative surveys

Time Trends in Income-related Differences in Food Group Intakes: The National Health and Nutrition Survey, Japan in 2010, 2014, and 2018

BACKGROUND

We aimed to clarify whether differences in food group intake according to household income have changed over the last decade in Japanese people aged 20 years or older.

METHODS

This cross-sectional study was based on the 2010, 2014, and 2018 National Health and Nutrition Surveys in Japan. Food intake was assessed using a 1-day semi-weighed household dietary record. The participants were categorized into three groups based on their income. The mean of each food intake according to the income group was estimated by adjusting for age, occupation, and number of participants from the same household. The significance of the interaction terms between income and survey year was evaluated to assess the change in income-related differences in food intake over time.

RESULTS

Cereal intake was lower in the middle- and the highest-income groups than in the lowest-income group, regardless of sex, and the interaction between income and year was nonsignificant for cereal intake. In the former two surveys, vegetable intake was higher among the highest-income women, while in the 2018 survey, the vegetable intake decreased in the women in the middle- and the highest-income groups. The interaction between income and year was significant for vegetable intake among the women. For other foods, the differences in intake among the income groups did not significantly change over time.

CONCLUSION

The tendency for lower cereal intake in the higher-income groups was consistent over time in both the sexes, and the tendency for higher vegetable intake in the highest income women disappeared over time.

Association of monetary diet cost of foods and diet quality in Spanish older adults

Background

A major barrier to a healthy diet may be the higher price of healthy foods compared to low-quality foods.

Objectives

This study aimed to assess the association between the monetary cost of food and diet quality in Spanish older adults at high risk of cardiovascular disease.

Methods

Cross-sectional analysis was carried out in Spanish older adults (n = 6,838; 48.6% female). A validated food frequency questionnaire was used to assess dietary intake. Metabolic syndrome severity, adherence to the Mediterranean diet (MedDiet), adherence to a provegetarian dietary pattern, and dietary inflammatory index were assessed. The economic cost of the foods was obtained from the Spanish Ministry of Agriculture Fisheries and Food database (2015-2017, the period of time when the participants were recruited). The total cost of diet adjusted per 1,000 kcal was computed.

Results

The healthier dietary pattern was associated with a higher cost of the diet. Higher adherence to the MedDiet, anti-inflammatory diet, and the healthy version of the provegetarian dietary pattern were related to higher costs of the diet.

Conclusion

Higher diet quality was associated with a higher dietary cost of the diet per 1,000 kcal/day. Food prices can be an important component of interventions and policies aimed at improving people's diets and preventing diet-related chronic diseases.

Clinical trial registry number

The trial was registered in 2014 at the International Standard Randomized Controlled Trial (ISRCT; http://www.isrctn.com/ISRCTN89898870) with the number 89898870.

Exploring culturally acceptable, nutritious, affordable and low climatic impact diet for Japanese diets: proof of concept of applying a new modelling approach using data envelopment analysis

A future sustainable dietary pattern for Japanese is yet undefined. This study aimed to explore more sustainable Japanese diets that are nutritious, affordable and with low greenhouse gas emissions (GHGE) and particular emphasis on cultural acceptability. A newly developed data envelopment analysis (DEA) diet model was applied to 4-d dietary record data among 184 healthy Japanese men and 185 women volunteers aged 21-69 years. Alternative diets were calculated as the linear combinations of observed diets. Firstly, for each individual, four modelled diets were calculated that maximised cultural acceptability (i.e. minimise dietary change from observed diet), maximised nutritional quality assessed by the Nutrient-Rich Food Index (NRF), minimised monetary diet costs or minimised diet-related GHGE. The final modelled diet combined all four indicators. In the first four models, the largest improvement was obtained for each targeted indicator separately, while relatively small improvements or unwanted changes were observed for other indicator. When all indicators were aimed to optimise, the NRF score and diet-related GHGE were improved by 8-13 % with the lower monetary cost than observed diets, although the percentage improvement was a bit smaller than the separate models. The final modelled diets demanded increased intakes for whole grains, fruits, milk/cream/yogurt, legumes/nuts, and decreased intakes for red and processed meat, sugar/confectioneries, alcoholic and sweetened beverages, and seasonings in both sexes. In conclusion, more sustainable dietary patterns considering several indicators are possible for Japanese, while total improvement is moderate due to trade-offs between indicators and methodological limitation of DEA diet model.

Socioeconomic and sociodemographic factors associated with food expense insufficiency during the COVID-19 pandemic in Japan

OBJECTIVE

To examine the status of food expense insufficiency in Japan during the coronavirus disease 2019 (COVID-19) pandemic and the socioeconomic and sociodemographic factors associated with food expense insufficiency.

DESIGN

Food expense insufficiency before and after the pandemic was assessed. The multivariable-adjusted odds ratio (AOR) and 95% confidence interval (CI) were calculated for the association between food expense insufficiency and socioeconomic and sociodemographic factors.

SETTING

A large-scale, cross-sectional online questionnaire survey.

PARTICIPANTS

From August to September 2020, 25,482 participants aged 15-79 years completed the questionnaire (JACSIS 2020 study; Group 1). In October 2020, 917 single parents were surveyed for oversampling purposes. There were 179 single parents in Group 1 and a total of 1096 single parents in Group 2.

RESULTS

Group 1 and Group 2 had 747 (2.9%) and 55 (5.0%) participants, respectively, who experienced food expense insufficiency for the first time after April 2020. Young age, part-time employment, being a single parent (in Group 1), and the number of people in the household (five or more in Group 1 and child/children alone in Group 2) were significantly associated with food expense insufficiency. As being a single parent was significantly associated with food expense insufficiency in Group 1 (AOR [95% CI] = 7.23 [5.40-9.68]), we further examined it in Group 2. Single parents who exhibited multiple factors (young age, part-time employment, living only with child/children) were likely to experience food expense insufficiency (15.3-15.8%).

CONCLUSIONS

Triggered by the pandemic, a small percentage of individuals experienced food expense insufficiency. We identified that factors such as young age, part-time employment, and being a single parent were significantly associated with food expense insufficiency, and discovered that a multiplicity of these factors further increased the risk. Our findings suggest an urgent need to support individuals with a potentially high risk of food expense insufficiency.

Diet quality and physical or comprehensive frailty among older adults

PURPOSE

While the association between diet quality and mortality has been previously demonstrated, the association between frailty and diet quality has not been evaluated well. This study aimed to investigate the association between diet quality and prevalence of both physical and comprehensive frailty, using two validated tools, in a community-based cohort of older adults.

METHODS

We conducted cross-sectional analyses using baseline data of 7022 participants aged ≥ 65 years in the Kyoto-Kameoka study. Diet quality was assessed by calculating the adherence scores to the Japanese Food Guide Spinning Top using a validated questionnaire; the participants were stratified into quartile groups based on these scores. Physical and comprehensive frailty was assessed using the Fried phenotype model-based Frailty Screening Index and the Kihon Checklist, respectively. Multivariable logistic regression and the restricted cubic spline model were used to calculate odds ratios (ORs) and their 95% confidence intervals (CIs) for associations between adherence scores and frailty prevalence.

RESULTS

Higher adherence scores signified a higher intake of vitamin C, vegetables, dairy products, and fruits. Physical and comprehensive frailty prevalence was 14.2 and 35.8%, respectively. In a multivariable adjusted model, compared with the bottom adherence score quartile, the top quartile was associated with lower ORs of physical (OR 0.64; 95% CI 0.52-0.80) and comprehensive frailty (OR 0.60; 95% CI 0.51-0.71). These relationships were similar to results in the spline model.

CONCLUSIONS

This study shows an inverse dose-response relationship between diet quality and prevalence of both physical and comprehensive frailty in older adults.

Feasibility and measurement error in using food supply data to estimate diet costs in Canada

OBJECTIVE

The cost of food is a key influence on diet. The majority of diet cost studies match intake data from population-based surveys to a single source of food supply prices. Our aim was to examine the methodological significance of using food supply data to price dietary intakes.

METHODS

Nationally representative 24-hour dietary recall data from the 2015 Canadian Community Health Survey-Nutrition (CCHS-N) was matched to the 2015 Canadian Consumer Price Index (CPI) food price list. Proportions and means of reported intakes covered by the 2015 CPI price list were used to compare reported intakes of food groups and food components of interest and concern overall, and by quartile of CPI coverage.

SETTING

Canada.

PARTICIPANTS

20,487 Canadians ages one and older.

RESULTS

The CPI covered on average 76.3% of total dietary intake (g) without water. Staple food groups that were more commonly consumed had better CPI price coverage than those less commonly consumed. Yet some food groups (vegetables, additions, sweets) that were also commonly consumed by Canadians were not well covered by price data. Individuals in the poorest CPI coverage quartile reported consuming significantly greater fibre (g), gram weight (g), dietary fibre (g), and energy (kcal) as compared to those with the best coverage.

CONCLUSIONS

Differential CPI price coverage exists among food components and commonly consumed food groups; additionally dietary intake differs significantly in the population by CPI coverage. Methodological refinements are needed to better account for error when using prices from food supply data to estimate diet costs.

Convenience Food Options and Adequacy of Nutrient Intake among School Children during the COVID-19 Pandemic

The COVID-19 pandemic has caused changes in the family food environment, resulting in more families relying on convenience food options. This study aimed to investigate diet quality by convenience food options (namely instant, frozen, and take-out foods) among Japanese school children during the COVID-19 pandemic. We examined the relationship between the frequency of consumption of convenience food options and nutritional status of the school children. The participants (671 children, 10–14 years old) were chosen to form a nationally representative sample of the Japanese population. Using questionnaires completed by the participants’ guardians, information was collected on the frequency of instant, frozen, and take-out food consumption. Habitual food and nutrient intake were collected using a validated food frequency questionnaire, completed by the children with help from their guardian(s). “Frequent” consumption was defined as consumption of instant, frozen, and/or take-out foods on more than 5 days per week. Using 19 nutrients and their respective dietary reference intake (DRI) values, an index was created to label each child’s nutrient intake as “Adequate”, “Inadequate”, “Excess”, or “Deficient.” Compared to children with non-frequent consumption, school children with frequent instant food consumption had significantly higher rates of inadequate nutrient intake (risk ratio (RR) = 3.0 [95% CI: 1.6–5.6]) and excess nutrient intake (RR = 2.3 [95% CI: 1.3–4.2]), while school children with frequent take-out food consumption had significantly higher rates of inadequate nutrient intake (RR = 2.1 [95% CI: 1.3–3.3]). There were no significant differences for children with frequent frozen-food intake. These associations did not change when adjusting for sociodemographic factors. Our results suggest that the frequent consumption of instant or take-out foods among school children results in non-adequate nutritional intake.

Replacing ultra-processed foods with fresh foods to meet the dietary recomendations: a matter of cost?

The study aimed to analyze the economic impact of the adoption of optimized and nutritionally balanced diets to Brazilian families, considering the Brazilian dietary guidelines and the economic disparities of the population. Data from the Brazilian Household Budget Survey from 2008-2009 (550 strata; 55,970 households) were used. About 1,700 foods and beverages purchased by the Brazilians were classified into 4 groups according to NOVA system. Linear programming models estimated isoenergetic diets preserving the current diet as baseline and optimizing healthier diets gradually based on the "golden rule" of the Brazilian dietary guidelines, respecting nutritional restrictions for macronutrients and micronutrients (based on international recommendations) and food acceptance limits (10th and 90th percentiles of the per capita calorie distribution from the population). The diet cost was defined based on the sum of the average cost of each food group, both in the current and optimized diets (BRL per 2,000Kcal/person/day). The economic impact of the Brazilian dietary guidelines to Brazilian household budget was analyzed by comparison the cost of the optimized diets to the cost of the current diet, calculated for the total population and by income level. Three healthier diets were optimized. Current diet cost was BRL 3.37, differed among low- and high-income strata (BRL 2.62 and BRL 4.17, respectively). Regardless of income, diet cost decreased when approaching the guidelines. However, low-income strata compromised their household budget more than two times the high-income strata (20.2% and 7.96%, respectively). Thus, the adoption of healthier eating practices can be performed with the same or lower budget.

Changes in Selected Food Groups Consumption and Quality of Meals in Japanese School Children during the COVID-19 Pandemic

In 2020, a state of emergency was declared to control the devastating impact of coronavirus, leading to temporary school closures in Japan, meaning that school lunches were not provided to the majority of schoolchildren. Using questionnaires completed by participants' guardians, we examined the relationship between household income and the quality of meals in Japanese schoolchildren before, during, and after the state of emergency. Participants (1111 children, 10-14 years old) were chosen to form a nationally representative sample of the Japanese population. "Well-balanced dietary intake" was defined as the intake of (i) meat, fish, or eggs and (ii) vegetables. The desired prevalence was defined as equal to or more than twice a day. Household income was divided into quartiles. "Well-balanced dietary intake" was lower in all households during the state of emergency compared with before. The proportion of those with a "well-balanced dietary intake" at least twice a day was notably low in both Q3 and Q4 during the state of emergency compared with before the declared state of emergency; relative risk increase (95% CI) were Q1: -19.0% (-19.6% to -18.4%), p < 0.001, Q2: -21.3% (-22.1% to -20.6%) p < 0.001, Q3: -25.4% (-26.1% to -24.7%), p < 0.001, and Q4: -34.8% (-35.6% to -34.0%), p < 0.001. The interaction p (vs. Q1) of Q2, Q3, and Q4 were all <0.001. Guardians from low-income households had significantly higher rates of having less: time, psychological room, and financial position to prepare meals during the state of emergency. Our results suggest that schoolchildren's quality of meals worsened during the state of emergency, especially in low-income households, because school lunches were not provided.

Nutrient adequacy of Japanese schoolchildren on days with and without a school lunch by household income

Background

Evidence for whether the nutrient intakes of Japanese schoolchildren differ according to household income is sparse.

Objective

We investigated the role of school lunches for nutrient adequacy among Japanese primary school children using dietary reference intakes in a cross-sectional survey.

Design

Participants were 10- to 11-year-old (5th grade) children from 19 public primary schools in four prefectures of East Japan, and 836 children were analyzed. The participants completed 24-h dietary records with photographs of their meals for 4 consecutive days, composed of 2 days with and 2 days without a school lunch. −Children’s household income was obtained from questionnaires that were completed by the participants’ guardians and divided into the following three categories: low (0.2236–2.2361 million yen; n = 319), middle (2.3333–2.8868 million yen; n = 194), and high (3.1305–6.3640 million yen; n = 323). Logistic regression analyses were used to estimate the odds ratios for whether participants had poor nutrient intakes, with adjustment for confounders.

Results

On days without a school lunch, the prevalence of nutrient shortages was significantly higher compared with those on days with a school lunch for most macro- and micronutrients among all three levels of household income. Children from low-income households had higher rates of nutrient shortages for vitamin B₆, pantothenic acid, K, Mg, P, Fe, and Zn than those from middle-income households on days without a school lunch (P = 0.004, 0.001, 0.001, 0.006, 0.037, <0.001, and 0.015, respectively), but those differences were not significant on days with a school lunch.

Conclusion

The findings suggest that school lunches are important for achieving adequate nutrient intakes in schoolchildren and reduce disparities of adequate nutrient intake by household income levels.

Diet quality of Japanese adults with respect to age, sex, and income level in the National Health and Nutrition Survey, Japan

Objective:

Although several studies in Western countries show that higher socioeconomic status is associated with higher diet quality, no study has observed this association in Japan. In the current study, we examined the association between diet quality and the combinations of age, sex, and household income, and also compared the dietary intake between diet quality levels according to household income.

Design:

Cross-sectional study.

Setting:

National Health and Nutrition Survey, Japan in 2014.

Participants:

2785 men and 3215 women.

Results:

Higher Japanese Food Guide Spinning Top scores (better diet quality) were observed in older women, especially those with higher household income, whereas lower scores were observed in younger men with lower household income. Those having low quality diet, especially in low income households, had higher odds of not meeting the recommended amounts of the Japanese dietary guidelines, than those having high quality diet.

Conclusions:

Diet quality in Japanese adults differed by age and sex as well as by household income level. A different approach to diet quality improvement is needed according to population characteristics including not only age and sex but also social economic status.

Association between socioeconomic status and small-for-gestational-age in Japan: A single center retrospective cohort study

AIM

Small-for-gestational-age (SGA) status has negative health consequences in neonates and later life. Low socioeconomic status (SES) is a reported risk factor for adverse birth outcomes, such as SGA and preterm birth (PTB). The present study investigated whether maternal SES is associated with adverse outcomes in Japanese pregnant women.

METHODS

Retrospective data were collected for 1970 Japanese women with singleton pregnancies who delivered between January 2007 and December 2011 at a single center: low SES group (n = 197); and controls (n = 1773). Low SES was defined according to the criteria of the Japanese pregnant-childbirth hospitalization support policy system.

RESULTS

The low SES group included a significantly higher proportion of young women, women with single marital status, greater parity, pre-pregnancy smoking and a lack of regular employment (P < 0.001, respectively). The crude odds ratio (OR) for the association between low maternal SES and SGA was 1.80 (95% confidence interval [CI] 1.15-2.82, P = 0.010). After adjustment for baseline maternal age, parity, body mass index, smoking and gestational weight gain, the adjusted OR for the association between low maternal SES and SGA was 1.92 (95% CI 1.17-3.17, P = 0.010). No significant association was found between maternal SES and PTB.

CONCLUSION

The present results suggest that low maternal SES is associated with SGA births in the Japanese population. Mitigation of low maternal SES could be urgent public health to prevent disadvantage birth outcome.

Effectiveness of a community-based intervention for weight loss on cardiometabolic risk factors among overweight and obese women in a low socio-economic urban community: findings of the MyBFF@home

BACKGROUND

The effectiveness of lifestyle intervention for weight loss on cardiometabolic risk factors among overweight and obese individuals in the community setting remains inconclusive. This study aimed to evaluate the effect of a 6-month weight loss lifestyle intervention on cardiometabolic risk factors among overweight and obese women and the sustainability of the changes in those markers at 12-month follow-up, comparing an intervention group with a control group.

METHODS

A total of 243 participants from MyBFF@home were included in this study. Fasting blood samples at baseline, 6- and 12-month were assessed for fasting plasma glucose (FPG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides. The effect of the intervention on cardiometabolic risk markers were investigated within and between study groups using t-test and general linear model (GLM) repeated measure ANOVA.

RESULTS

Results from repeated measures ANOVA showed intervention effect only in TC where significant reduction was found in the intervention group (- 0.26 mmol/L [95% CI: - 0.47 to - 0.06], p < 0.01) compared to the control group (- 0.06 mmol/L [95% CI: - 0.28 to 0.17]) at 12 months. At 6 months, TC was reduced significantly in both groups but only intervention group retained the reduction in maintenance phase while, the level increased significantly in the control group (0.22 mmol/L [95% CI: 0.06 to 0.38]). This attributed to significant increase in TC/HDL-C ratio in the control group during maintenance phase (0.32 [95% CI: 0.15 to 0.50], p < 0.001). The intervention group also showed trend of reduction in FPG at 6 months and further decreased during maintenance phase (- 0.19 mmol/L [95% CI: - 0.32 to - 0.06], p < 0.01). At 6 months HDL-C was maintained in the intervention group but reduced significantly in the control group (- 0.05 mmol/L [95% CI: - 0.10 to - 0.01], p < 0.05). No significant difference was detected in both markers when compared between groups.

CONCLUSIONS

In the context of low socio-economic communities, this study supports that weight loss related lifestyle modifications over a 6-month period could improve selected cardiometabolic risk factors, particularly fasting glucose, TC and HDL-C in overweight and obese women with favourable sustainability over a 12-month period.

Relationships among Food Group Intakes, Household Expenditure, and Education Attainment in a General Japanese Population: NIPPON DATA2010

BACKGROUND

A lower socioeconomic status (SES) may be related to the intake of unhealthy food; however, this relationship has not been examined in detail. This study was undertaken to examine relationships among food group intakes and SES in a representative Japanese population.

METHODS

This was a cross-sectional study using the baseline data of NIPPON DATA2010, which is a prospective cohort study of the National Health and Nutrition Survey in Japan. A total of 2,898 participants were included in the baseline survey in 2010. The effects of age (<65 years and ≥65 years), equivalent household expenditure (EHE), and education attainment on food group intakes (gram per 1,000 kcal) were analyzed using a two-way analysis of variance.

RESULTS

When EHE was lower, cereal intake was higher in men and women. Among men, fish, milk, and alcohol intakes were reduced with lower EHE. Among women, vegetable intake was reduced with lower EHE. In men and women, cereal intake was higher with lower education attainment. In contrast, meat intake was reduced with lower education attainment.

CONCLUSIONS

Lower SES was associated with a higher cereal intake and lower vegetable, fish, meat, and milk intakes in a representative Japanese population. Socioeconomic discrepancies need to be considered in order to promote healthier dietary habits.

Higher Dietary Cost Is Associated with Higher Diet Quality: A Cross-Sectional Study among Selected Malaysian Adults

Food price is a determining factor of food choices; however its relationship with diet quality is unclear in Malaysia. This study aimed to examine socio-economic characteristics and daily dietary cost (DDC) in relation to diet quality in the state of Selangor, Malaysia. Dietary intake was assessed using a Food Frequency Questionnaire (FFQ) and diet quality was estimated using a Malaysian Healthy Eating Index (M-HEI). DDC in Malaysian Ringgit (RM) was calculated from dietary intake and national food prices. Linear regression models were fitted to determine associations between DDC and M-HEI scores and predictors of diet quality. The mean M-HEI score of respondents was 61.31 ± 10.88 and energy adjusted DDC was RM10.71/2000 kcal (USD 2.49). The highest quintile of adjusted DDC had higher M-HEI scores for all respondents (Q1: 57.14 ± 10.07 versus Q5: 63.26 ± 11.54, p = 0.001). There were also positive associations between DDC and M-HEI scores for fruits (p < 0.001) and vegetables (p = 0.017) for all respondents. Predictors of diet quality included carbohydrate (β = 0290; p < 0.001) and fat intakes (β = −0.242; p < 0.001) and energy adjusted DDC (β= 0.196; p < 0.001). Higher dietary cost is associated with healthy eating among Malaysian adults.

Household income is associated with food and nutrient intake in Japanese schoolchildren, especially on days without school lunch

Objective

The present study aimed to examine the association between household income and the intake of foods and nutrients by Japanese schoolchildren, and any differences between days with and without school lunch.

Design

This was a cross-sectional study. Children, with the support of their parents, kept dietary records with photographs for 4 d (2 d with school lunch and 2 d without). The socio-economic status of each family was obtained from a questionnaire completed by the parents.

Setting

Japan.

Subjects

All students in 5th grade (10–11 years old) at nineteen schools in four prefectures and their parents (1447 pairs of students and parents) were invited to take part in the study; 836 pairs of complete data sets were analysed.

Results

The average results of four days of dietary records showed that lower income level was associated with a lower intake of fish/shellfish, green vegetables and sugar at the food group level, a lower intake of protein and several micronutrients, and a higher energy intake from carbohydrates at the nutrient level among the children. These associations between income and food/nutrient intake were not significant on days with school lunches, but were significant on days without school lunch.

Conclusions

Our study confirmed an association between household income and the amount of foods and nutrients consumed by Japanese schoolchildren, and suggested that school lunches play a role in reducing disparities in the diets of children from households with various incomes.