Monetary cost of self-reported diet in relation to biomarker-based estimates of nutrient intake in young Japanese women

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.

Monetary diet cost is positively associated with diet quality and obesity: an analysis of school-aged children in Southwest China

BACKGROUND

Little is known about the relationships between diet cost, dietary intake and obesity in Chinese populations. This study explored how diet cost was related to diet quality and obesity among school-aged children in Southwest China.

METHODS

Data from a cross-sectional study was analysed. Diet cost was estimated based on dietary intake assessed with 24-h dietary recalls and retail food prices. Diet quality was measured using the Chinese Children Dietary Index. Body height, weight, waist circumference and skinfold thicknesses were measured, and their body mass index standard deviation score (BMISDS), waist-to-height ratio (WHtR), fat mass index (FMI) and fat-free mass index (FFMI) were calculated. Multivariate regression models were used to explore the relevance of diet cost to diet quality and obesity.

RESULTS

After adjustment for potential confounders, a positive association was observed between diet quality and energy-adjusted diet cost (β = 0.143, 95% confidence interval, CI: 0.014-0.285, Pfor-trend = 0.0006). Energy-adjusted diet cost also showed a positive association with FMI (β = 0.0354, 95% CI: 0.0001-0.0709, Pfor-trend = 0.01), BMISDS (β = 0.0200, 95% CI: 0.0006-0.0394, Pfor-trend = 0.002) and WHtR (β = 0.0010, 95% CI: 0.0003-0.0017, Pfor-trend = 0.02).

CONCLUSIONS

Energy-adjusted diet cost was independently and positively associated with diet quality and obesity among Chinese school-aged children.

Longitudinal Associations between Monetary Value of the Diet, DASH Diet Score and the Allostatic Load among Middle-Aged Urban Adults

Lower cost can lead to poorer-quality diets, potentially worsening metabolic profiles. We explored these pathways among urban adults. Longitudinal data were extracted from 1224-1479 participants in the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study. DASH(mean) (Dietary Approaches to Stop Hypertension) score was computed using four 24 h recalls (v1/v2: 2004-2013) linked with a national food price database to estimate monetary value of the diet [MVD(mean)]. Allostatic load (AL) was measured at visits 2 (v2) and 3 (v3) in 2009-2018. Mixed-effects regression and structural equation modeling (SEM) were conducted, linking MVD(mean)/DASH(mean) to AL [v2 and annual change(v3-v2)] and exploring mediating pathways between MVD(mean) and AL(v3) through DASH(mean), stratifying by sex, race and poverty status. MVD(mean) tertiles were linearly associated with contemporaneous DASH(mean), after energy adjustment. In mixed-effects regression models, DASH(mean) was consistently linked to lower AL(v2). DASH(mean) and MVD(mean) were positively associated with higher serum albumin(v2). In SEM, MVD(mean) was linked to AL(v3) through DASH(mean), mainly among Whites and specifically for the cholesterol and Waist-Hip-Ratio AL components. In summary, energy and other covariate-adjusted increase in MVD may have a sizeable impact on DASH which can reduce follow-up AL among urban White middle-aged adults. More studies are needed to replicate findings in comparable samples of urban adults.

Socioeconomic and ethnic differences in the relation between dietary costs and dietary quality: the HELIUS study

BACKGROUND

Healthier dietary patterns are generally more costly than less healthy patterns, but dietary costs may be more important for dietary quality in lower educated and ethnic minority groups. The aim of this study was to investigate the association between dietary costs and dietary quality and interactions with ethnicity and socioeconomic position (SEP).

METHODS

We used cross-sectional data from 4717 Dutch, Surinamese, Turkish and Moroccan origin participants of the multi-ethnic HELIUS study (the Netherlands), who completed an ethnic-specific food frequency questionnaire (FFQ). The primary outcome measure was dietary quality according to adherence to the Dutch Healthy Diet index 2015 (DHD15-index, range 0-130). Individual dietary costs (the monetary value attached to consumed diets in Euros) were estimated by merging a food price variable with the FFQ nutrient composition database. Regression analyses were used to examine main and interaction effects. Analyses were adjusted for age, sex, smoking, energy intake, physical activity, ethnicity and educational level.

RESULTS

Having higher dietary costs was associated with higher dietary quality. Analyses stratified by educational level showed that associations were stronger in higher educated (Btertile3 = 8.06, 95%CI = 5.63; 10.48) than in lower educated participants (Btertile3 = 5.09, 95%CI = 2.74; 7.44). Stratification by ethnic origin showed strongest associations in Turkish participants (Btertile2 = 9.31, 95%CI = 5.96; 12.65) and weakest associations in Moroccan participants (Btertile3 = 4.29, 95%CI = 0.58; 8.01). Regardless of their level of education, Turkish and Moroccan individuals consumed higher quality diets at the lowest cost than Dutch participants.

CONCLUSIONS

The importance of dietary costs for dietary quality differs between socioeconomic and ethnic subgroups. Increasing individual food budgets or decreasing food prices may be effective for the promotion of healthy diets, but differential effects across socioeconomic and ethnic subgroups may be expected.

Longitudinal change in the diet's monetary value is associated with its change in quality and micronutrient adequacy among urban adults

Background

Reducing diet costs may lead to the selection of energy-dense foods, such as refined grains or foods high in added sugars and/or fats, which can lower overall dietary quality. We examined the longitudinal association between the monetary value of the diet (MVD) and the overall dietary quality across sex, race and income groups.

Methods and findings

Longitudinal data from 1,466 adult urban participants from Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study were used. Healthy Eating Index–2010 (HEI–2010) and Mean Adequacy Ratio (MAR) were computed and a national food price database was used to estimate MVD. Multiple linear regression analyses were conducted linking annual rates of change (Δ) in MVD to ΔHEI-2010 and ΔMAR, stratifying by sex, race and income groups. Among key findings, ΔHEI-2010 was comparable across socio-demographic groups, while ΔMAR was higher among women and individuals above poverty. Adjusting for key covariates, ΔMVD was positively associated with both ΔHEI-2010 and ΔMAR, and with a consistently stronger association among individuals above poverty, specifically for the total proteins and empty calories components of HEI-2010 and several nutrient adequacy ratios (NARs: vitamins C, E, B-6 and Zinc). ΔMVD-ΔMAR association was stronger in women, mainly influenced by ΔMVD’s positive associations with B-vitamins, copper, calcium, magnesium and phosphorus NARs. ΔMVD-Δvitamin D NAR’s positive relationship was stronger among Whites, while ΔMVD-Δvitamin B-12 NAR’s association was stronger among African-Americans.

Conclusions

In sum, a potential increase in MVD may have a stronger impact on dietary quality among urban adult women and above-poverty individuals.

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.

Nutritional correlates of monetary diet cost in young, middle-aged and older Japanese women

Studies in many Western countries have consistently shown that monetary diet cost is positively associated with diet quality, but this may not necessarily be the case in Japan. This cross-sectional study examined the nutritional correlates of monetary diet cost among 3963 young (all 18 years old), 3800 middle-aged (mean age 48 years) and 2211 older (mean age 74 years) Japanese women. Dietary intakes were assessed using a comprehensive self-administered diet history questionnaire for young and middle-aged women and a brief self-administered diet history questionnaire for older women. Monetary diet cost was estimated using retail food prices. Total vegetables, fish and shellfish, green and black tea, white rice, meat, fruit and alcoholic beverages contributed most (79–89 %) to inter-individual variation in monetary diet cost. Multiple regression analyses showed that monetary diet cost was negatively associated with carbohydrate intake, but positively with intakes of all other nutrients examined (including not only dietary fibre and key vitamins and minerals but also saturated fat and Na) in all generations. For food group intakes, irrespective of age, monetary diet cost was associated inversely with white rice and bread but positively with pulses, potatoes, fruit, total vegetables, fruit and vegetable juice, green and black tea, fish and shellfish, and meat. In conclusion, in all three generations of Japanese women and contrary to Western populations, monetary diet cost was positively associated with not only healthy dietary components (including fruits, vegetables, fish and shellfish, dietary fibre, and key vitamins and minerals), but also less healthy components (including saturated fat and Na).

Association between energy density and diet cost in children

Highlights

The average of the energy-adjusted diet cost in 6-12 years-old children was 2.17€/1000Kcal (SD + 0.49).Energy-density diets (EDs - Kcal/g) were calculated by three distinct methods: (1) with food and all beverages (ED1), (2) with food and caloric beverages (ED2), and (3) only with food (ED3).The distributions of the three EDs were statistically different, being higher the ED3 - calculated excluding all beverages (1.15Kcal (SD + 0.28) vs. ED2: 1.10Kcal/g; SD + 0.24 vs. ED1: 0.99Kcal/g; SD + 0.22).Lower energy-density diets (EDs) were associated with higher diet cost in a sample of school children from a Mediterranean country, regardless the differences between the EDs calculated by three distinct methods.

Background

Lower energy density diets tend to cost more, but data using different ways to calculate the dietary energy density, is scarce.

Objectives

To estimate the dietary energy density, and to assess how it is associated with the diet cost in children.

Methods

Data were obtained from a community-based survey from public elementary schools in Portugal. Dietary intake of 464 children (6-12 years) was assessed by a 24 h recall in 2007/2008. Dietary energy density (kcal/g) was calculated as following: (1) with food and all beverages (ED1), (2) with food and caloric beverages (ED2), and (3) only with food (ED3). Energy-adjusted diet cost (€/1000 kcal) was calculated based on the collection of food prices from a national leader supermarket. Anthropometric measures were taken and socio-demographic data were obtained from parents. Logistic regression was used to estimate the association between diet cost and energy density.

Results

For boys, the energy-adjusted diet cost of the highest third of energy density was lower, between 81% in the ED3 (p for trend <0.001) and 87% in the ED1 (p for trend <0.001), compared to the lowest third. Girls showed similar, but weaker associations.

Conclusions

Higher dietary energy density was associated with lower dietary cost among children.

Monetary Value of Diet Is Associated with Dietary Quality and Nutrient Adequacy among Urban Adults, Differentially by Sex, Race and Poverty Status

OBJECTIVE

The association between monetary value of the diet (MVD, $/day) with dietary quality was examined using a large sample of urban US adults, differentially by socio-demographic factors.

METHODS

This was a cross-sectional study of 2,111 participants, aged 30-64y, using data from the Healthy Aging in Neighborhoods of Diversity across the Life Span Study. Dietary quality indices included Healthy Eating Index-2010 (HEI-2010) and Mean Adequacy Ratio (MAR), (two 24-hr recalls). A national food price database was used to estimate MVD. Multiple linear/logistic regression analyses were conducted stratifying separately by sex, race and poverty status.

RESULTS

Women had significantly higher HEI-2010 scores than men (43.35 vs 41.57 out of 100, respectively), whereas MAR scores were higher for men (76.8 vs 69.9, out of 100), reflecting energy intake gender differentials. Importantly, a $3/day higher MVD (IQR: $3.70/d (Q1) to $6.62/d (Q4)) was associated with a 4.98±0.35 higher total HEI-2010 and a 3.88±0.37 higher MAR score, after energy-adjustment and control for key confounders. For HEI-2010 and MAR, stronger associations were observed among participants above poverty and among women, whilethe MVD vs. HEI-2010 association was additionally stronger among Whites. Sex and poverty status differentials were observed for many MAR and some HEI-2010 components.

CONCLUSIONS

Despite positive associations between measures of dietary quality and MVD, particularly above poverty and among women, approaching compliance with the Dietary Guidelines (80 or more for HEI-2010) requires a substantially higher MVD. Thus, nutrition education may further improve people's decision-making regarding food venues and dietary choices.

Does the importance of dietary costs for fruit and vegetable intake vary by socioeconomic position?

Evidence suggests that diets meeting recommendations for fruit and vegetable (F&V) intake are more costly. Dietary costs may be a greater constraint on the diet quality of people of lower socioeconomic position (SEP). The aim of this study was to examine whether dietary costs are more strongly associated with F&V intake in lower-SEP groups than in higher-SEP groups. Data on individual participants’ education and income were available from a population-based, cross-sectional study of 10 020 British adults. F&V intake and dietary costs (GBP/d) were derived from a semi-quantitative FFQ. Dietary cost estimates were based on UK food prices. General linear models were used to assess associations between SEP, quartiles of dietary costs and F&V intake. Effect modification of SEP gradients by dietary costs was examined with interaction terms. Analysis demonstrated that individuals with lowest quartile dietary costs, low income and low education consumed less F&V than individuals with higher dietary costs, high income and high education. Significant interaction between SEP and dietary costs indicated that the association between dietary costs and F&V intake was stronger for less-educated and lower-income groups. That is, socioeconomic differences in F&V intake were magnified among individuals who consumed lowest-cost diets. Such amplification of socioeconomic inequalities in diet among those consuming low-cost diets indicates the need to address food costs in strategies to promote healthy diets. In addition, the absence of socioeconomic inequalities for individuals with high dietary costs suggests that high dietary costs can compensate for lack of other material, or psychosocial resources.

Contribution of food prices and diet cost to socioeconomic disparities in diet quality and health: a systematic review and analysis

CONTEXT

It is well established in the literature that healthier diets cost more than unhealthy diets.

OBJECTIVE

The aim of this review was to examine the contribution of food prices and diet cost to socioeconomic inequalities in diet quality.

DATA SOURCES

A systematic literature search of the PubMed, Google Scholar, and Web of Science databases was performed.

STUDY SELECTION

Publications linking food prices, dietary quality, and socioeconomic status were selected.

DATA EXTRACTION

Where possible, review conclusions were illustrated using a French national database of commonly consumed foods and their mean retail prices.

DATA SYNTHESIS

Foods of lower nutritional value and lower-quality diets generally cost less per calorie and tended to be selected by groups of lower socioeconomic status. A number of nutrient-dense foods were available at low cost but were not always palatable or culturally acceptable to the low-income consumer. Acceptable healthier diets were uniformly associated with higher costs. Food budgets in poverty were insufficient to ensure optimum diets.

CONCLUSIONS

Socioeconomic disparities in diet quality may be explained by the higher cost of healthy diets. Identifying food patterns that are nutrient rich, affordable, and appealing should be a priority to fight social inequalities in nutrition and health.

The new nordic diet--consumer expenditures and economic incentives estimated from a controlled intervention

Background

Several studies suggest that a healthy diet with high emphasis on nutritious, low-energy components such as fruits, vegetables, and seafood tends to be more costly for consumers. Derived from the ideas from the New Nordic Cuisine – and inspired by the Mediterranean diet, the New Nordic Diet (NND) has been developed as a palatable, healthy and sustainable diet based on products from the Nordic region. The objective of the study is to investigate economic consequences for the consumers of the NND, compared with an Average Danish Diet (ADD).

Methods

Combine quantity data from a randomized controlled ad libitum dietary 6 month intervention for central obese adults (18–65 years) and market retail price data of the products consumed in the intervention. Adjust consumed quantities to market price incentives using econometrically estimated price elasticities.

Results

Average daily food expenditure of the ADD as represented in the unadjusted intervention (ADD-i) amounted to 36.02 DKK for the participants. The daily food expenditure in the unadjusted New Nordic Diet (NND-i) costs 44.80 DKK per day per head, and is hence about 25% more expensive than the Average Danish Diet (or about 17% when adjusting for energy content of the diet). Adjusting for price incentives in a real market setting, the estimated cost of the Average Danish Diet is reduced by 2.50 DKK (ADD-m), compared to the unadjusted ADD-i diet, whereas the adjusted cost of the New Nordic Diet (NND-m) is reduced by about 3.50 DKK, compared to the unadjusted NND-i. The distribution of food cost is however much more heterogeneous among consumers within the NND than within the ADD.

Conclusion

On average, the New Nordic Diet is 24–25 per cent more expensive than an Average Danish Diet at the current market prices in Denmark (and 16–17 per cent, when adjusting for energy content). The relatively large heterogeneity in food costs in the NND suggests that it is possible to compose an NND where the cost exceeds that of ADD by less than the 24–25 per cent.

Measuring diet cost at the individual level: a comparison of three methods

Background/objectives:

Household-level food spending data are not suitable for population-based studies of the economics of nutrition. This study compared three methods of deriving diet cost at the individual level.

Subjects/methods:

Adult men and women (n=164) completed 4-day diet diaries and a food frequency questionnaire (FFQ). Food expenditures over 4 weeks and supermarket prices for 384 foods were obtained. Diet costs (US$/day) were estimated using: (1) diet diaries and expenditures; (2) diet diaries and supermarket prices; and (3) FFQs and supermarket prices. Agreement between the three methods was assessed on the basis of Pearson correlations and limits of agreement. Income-related differences in diet costs were estimated using general linear models.

Results:

Diet diaries yielded mean (s.d.) diet costs of $10.04 (4.27) based on Method 1 and $8.28 (2.32) based on Method 2. FFQs yielded mean diet costs of $7.66 (2.72) based on Method 3. Correlations between energy intakes and costs were highest for Method 3 (r²=0.66), lower for Method 2 (r²=0.24) and lowest for Method 1 (r²=0.06). Cost estimates were significantly associated with household incomes.

Conclusion:

The weak association between food expenditures and food intake using Method 1 makes it least suitable for diet and health research. However, merging supermarket food prices with standard dietary assessment tools can provide estimates of individual diet cost that are more closely associated with food consumed. The derivation of individual diet cost can provide insights into some of the economic determinants of food choice, diet quality and health.

New metrics of affordable nutrition: which vegetables provide most nutrients for least cost?

Measuring food prices per gram, rather than per calorie, is one way to make healthful vegetables appear less expensive. However, a better measure of affordability would take the nutrient content of vegetables into account. This study, based on analyses of US Department of Agriculture datasets, aimed to identify which vegetables, including juices and soups, provided the most nutrients per unit cost. Nutrient density was measured using the Nutrient Rich Foods (NRF) index, based on nine nutrients to encourage: protein; fiber; vitamins A, C, and E; calcium; iron; magnesium; and potassium; and on three nutrients to limit: saturated fat, added sugar, and sodium. Food cost in dollars was calculated per 100 g, per 100 kcal, per serving, and per nutrient content. One-way analyses of variance with post hoc tests were used to determine statistical significance. Results showed that tomato juices and tomato soups, dark green leafy and nonleafy vegetables, and deep yellow vegetables, including sweet potatoes, had the highest NRF scores overall. Highest NRF scores per dollar were obtained for sweet potatoes, white potatoes, tomato juices and tomato soups, carrots, and broccoli. Tomato sauces, raw tomatoes, and potato chips were eaten more frequently than were many other vegetables that were both more affordable and more nutrient-rich. These new measures of affordable nutrition can help foodservice and health professionals identify those vegetables that provide the highest nutrient density per unit cost. Processed vegetables, including soups and juices, can contribute to the quality and the affordability of the diet.

Self-reported seafood intake and atopy in Japanese school-aged children

BACKGROUND

The effects of fish consumption and n-3 poly-unsaturated fatty acid (PUFA) levels on atopic disorders are inconsistent in previous reports, but few studies have investigated the effects of both fish and n-3 PUFA. The aim of the present study was to investigate whether erythrocyte fatty acids and the consumption of fish are associated with atopic diseases in pre- and early adolescents.

METHODS

A total of 135 students with eczema, 136 students with asthma, and 137 healthy control students were selected from fifth and eighth grades in Shunan, Japan. Atopic disorders and dietary intake were evaluated with questionnaires, and total serum IgE was measured using an enzyme-linked immunosorbent assay. In addition, erythrocyte membrane levels of PUFA were assessed via gas chromatography.

RESULTS

Total IgE was significantly elevated in the atopic subjects (P < 0.001). The intake of fatty and dried fish or seafood was significantly associated with eczema (odds ratios of the highest quartiles: 0.46, 95% confidence interval (95%CI): 0.22-0.94; 0.34, 95%CI: 0.16-0.71, respectively). Additionally, only erythrocyte eicosapentaenoic acid (EPA) level had a negative association with eczema (P= 0.048). For asthma, the effect of fish consumption was not significant.

CONCLUSIONS

Fish consumption was related to a low prevalence of eczema, but not asthma in Japanese pre- and early adolescents. EPA may be involved in this mechanism.

Improving nutrition in home child care: are food costs a barrier?

OBJECTIVE

Child-care providers have a key role to play in promoting child nutrition, but the higher cost of nutritious foods may pose a barrier. The present study tested the hypothesis that higher nutritional quality of foods served was associated with higher food expenditures in child care homes participating in the Child and Adult Care Food Program (CACFP).

DESIGN

In this cross-sectional study, nutritional quality of foods served to children and food expenditures were analysed based on 5 d menus and food shopping receipts. Nutritional quality was based on servings of whole grains, fresh whole fruits and vegetables, energy density (kJ/g) and mean nutrient adequacy (mean percentage of dietary reference intake) for seven nutrients of concern for child health. Food expenditures were calculated by linking receipt and menu data. Associations between food expenditures and menu quality were examined using bivariate statistics and multiple linear regression models.

SETTING

USA in 2008-2009.

SUBJECTS

Sixty child-care providers participating in CACFP in King County, Washington State.

RESULTS

In bivariate analyses, higher daily food expenditures were associated with higher total food energy and higher nutritional quality of menus. Controlling for energy and other covariates, higher food expenditures were strongly and positively associated with number of portions of whole grains and fresh produce served (P = 0·001 and 0·005, respectively), with lower energy density and with higher mean nutrient adequacy of menus overall (P = 0·003 and 0·032, respectively).

CONCLUSIONS

The results indicate that improving the nutritional quality of foods in child care may require higher food spending.

The quality and monetary value of diets consumed by adults in the United States

BACKGROUND

Food prices are an established determinant of food choice and may affect diet quality. Research on diet cost and diet quality in representative populations has been hindered by lack of data.

OBJECTIVE

We sought to explore the distribution of diet cost and diet quality among strata of the US population and to examine the association between the 2 variables.

DESIGN

In this cross-sectional study, monetary costs of diets consumed by participants in the 2001-2002 NHANES were estimated with the use of a national food price database. Healthy Eating Index (HEI)-2005 values were estimated with the use of the population ratio method for the calculation of average scores. Mean daily diet costs, energy-adjusted diet costs, and HEI-2005 scores were estimated for subpopulations of interest. Associations between energy-adjusted diet cost, HEI-2005 scores, and HEI-2005 component scores were evaluated.

RESULTS

Higher energy-adjusted diet costs were significantly associated with being older and non-Hispanic white, having a higher income and education, and living in a food-secure household. Higher diet costs were also associated with higher HEI-2005 scores for both men and women. Women in the highest quintile of diet costs had a mean HEI-2005 score of 69.6 compared with 52.5 for women in the lowest-cost quintile. Higher diet cost was strongly associated with consuming more servings of fruit and vegetables and fewer calories from solid fat, alcoholic beverages, and added sugars.

CONCLUSION

Given the observed association between diet cost and diet quality, helping consumers select affordable yet nutritious diets ought to be a priority for researchers and health professionals.

Are socio-economic disparities in diet quality explained by diet cost?

BACKGROUND

Socio-economic disparities in nutrition are well documented. This study tested the hypothesis that socio-economic differences in nutrient intakes can be accounted for, in part, by diet cost.

METHODS

A representative sample of 1295 adults in King County (WA) was surveyed in 2008-2009, and usual dietary intakes were assessed based on a food-frequency questionnaire. The monetary value of individual diets was estimated using local retail supermarket prices for 384 foods. Nutrients of concern as identified by the 2005 Dietary Guidelines Advisory Committee were fibre, vitamins A, C and E, calcium, magnesium and potassium. A nutrient density score based on all seven nutrients was another dependent measure. General linear models and linear regressions were used to examine associations among education and income, nutrient density measure and diet cost. Analyses were conducted in 2009-2010.

RESULTS

Controlling for energy and other covariates, higher-cost diets were significantly higher in all seven nutrients and in overall nutrient density. Higher education and income were positively and significantly associated with the nutrient density measure, but these effects were greatly attenuated with the inclusion of the cost variable in the model.

CONCLUSIONS

Socio-economic differences in nutrient intake can be substantially explained by the monetary cost of the diet. The higher cost of more nutritious diets may contribute to socio-economic disparities in health and should be taken into account in the formulation of nutrition and public health policy.

Relation of food cost to healthfulness of diet among US women

BACKGROUND

Few studies have evaluated the cost of a diet that may prevent cardiovascular disease. High scores on the Alternative Healthy Eating Index (AHEI) have been associated with lower rates of cardiovascular disease.

OBJECTIVE

We sought to evaluate the cost of a dietary pattern that may prevent cardiovascular disease among women residing in the United States.

DESIGN

By using food-cost data from the US Department of Agriculture, we explored relations between spending on food and AHEI scores among 78,191 participants in the Nurses' Health Study. By using linear regression, we estimated the change in AHEI score (range: 2.5-87.5) for a $1 increase in spending on various food groups.

RESULTS

Study participants in the highest energy-adjusted spending quintile spent 124% as much money each day as those in the lowest quintile. The difference in AHEI scores (10th-90th percentile) between all study participants was 30 index points (Spearman's correlation coefficient between total spending and AHEI = 0.44). The difference in AHEI scores (10th-90th percentile) within each quintile of spending ranged from 25 to 29 index points. Greater spending on nuts, soy and beans, and whole grains was associated with a higher AHEI score. Greater spending on red and processed meats and high-fat dairy was associated with a lower AHEI score.

CONCLUSIONS

Although spending more money was associated with a healthier diet, large improvements in diet may be achieved without increased spending. The purchase of plant-based foods may offer the best investment for dietary health.

Neighbourhood food store availability in relation to 24 h urinary sodium and potassium excretion in young Japanese women

Previous studies on the relationship of local food environment with residents' diets have relied exclusively on self-reported information on diet, producing inconsistent results. Evaluation of dietary intake using biomarkers may obviate the biases inherent to the use of self-reported dietary information. This cross-sectional study examined the association between neighbourhood food store availability and 24 h urinary Na and K excretion. The subjects were 904 female Japanese dietetic students aged 18-22 years. Neighbourhood food store availability was defined as the number of food stores within a 0.5-mile (0.8-km) radius of residence. Urinary Na and K excretion and the ratio of urinary Na to K were estimated from a single 24 h urine sample. After adjustment for potential confounding factors, neighbourhood availability of confectionery stores/bakeries was inversely associated with urinary K, and was positively associated with the ratio of Na to K (P for trend = 0.008 and 0.03, respectively). Neighbourhood availability of rice stores showed an independent inverse association with urinary K (P for trend = 0.03), whereas neighbourhood availability of supermarkets/grocery stores conversely showed an independent positive association with this variable (P for trend = 0.03). Furthermore, neighbourhood availability of fruit/vegetable stores showed an independent inverse association with the ratio of Na to K (P for trend = 0.049). In a group of young Japanese women, increasing neighbourhood availability of supermarkets/grocery stores and fruit/vegetable stores and decreasing availability of confectionery stores/bakeries and rice stores were associated with favourable profiles of 24 h urinary K (and Na) excretion.