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

Does an antihypertensive diet cost more? Analysis from the Chinese Heart-Healthy diet trial

OBJECTIVE

To determine whether the Chinese heart-healthy diet (Sichuan cuisine version) (CHH diet-SC) was more expensive than the conventional Sichuan diet and explore the food groups and nutrients that mainly affected the cost of CHH diet-SC.

DESIGN

Cost analysis of 4-week intervention diets in the Sichuan center representing southwestern China in the CHH diet study.

SETTING

A multicentre, parallel-group, single-blind, randomised feeding trial evaluating the efficacy of lowering blood pressure with the cuisine-based CHH diet.

PARTICIPANTS

Totally, fifty-three participants with hypertension aged 25-75 years in the Sichuan center were randomised into the control group (n 26) or the CHH diet-SC group (n 27).

RESULTS

The CHH diet-SC was more expensive than the control diet (¥27·87 ± 2·41 v. ¥25·18 ± 2·79 equals $3·90 ± 0·34 v. $3·52 ± 0·39, P < 0·001), and the incremental cost-effectiveness ratio for a 1-mm Hg systolic blood pressure reduction was ¥9·12 ($1·28). Intakes and the cost of seafood, dairy products, fruits, soybeans and nuts, whole grains and mixed beans were higher for the CHH diet-SC than for the control diet (P < 0·001). Intakes of vitamin B1, vitamin B6, vitamin C, Mg and phosphorus were positively correlated with the cost (P < 0·05).

CONCLUSIONS

The CHH diet-SC costs more than the conventional Sichuan diet, partly due to the high cost of specific food groups. Positive correlations between the intakes of vitamin B1, vitamin B6, vitamin C, Mg, phosphorus and the dietary cost could be a direction to adjust the composition within the food groups to reduce the cost of the CHH diet-SC.

Small increments in diet cost can improve compliance with the Dietary Guidelines for Americans

Adherence to the Dietary Guidelines for Americans (DGA) may involve higher diet costs. This study assessed the relation between two measures of food spending and diet quality among adult participants (N = 768) in the Seattle Obesity Study (SOS III). All participants completed socio-demographic and food expenditure surveys and the Fred Hutch food frequency questionnaire. Dietary intakes were joined with local supermarket prices to estimate individual-level diet costs. Healthy Eating Index (HEI- 2015) scores measured compliance with DGA. Multiple linear regressions using Generalized Estimating Equations with robust standard errors showed that lower food spending was associated with younger age, Hispanic ethnicity, and lower socioeconomic status. Even though higher HEI-2015 scores were associated with higher diet costs per 2000 kcal, much individual variability was observed. A positive curvilinear relationship was observed in adjusted models. At lower cost diets, a $100/month increase in cost (from $150 to $250) was associated with a 20.6% increase in HEI-2015. For higher levels of diet cost (from $350 to $450) there were diminishing returns (2.8% increase in HEI- 2015). These findings indicate that increases in food spending at the lower end of the range have the most potential to improve diet quality.

Associations of Education With Overall Diet Quality Are Explained by Different Food Groups in Middle-aged and Old Japanese Women

Background

The disparity of overall diet quality by personal educational attainment has been a public issue. However, it remains unknown which food groups contribute to the disparity. This cross-sectional study assesses which food groups explain associations between education and overall diet quality in Japanese women.

Methods

A total of 3,788 middle-aged (mean age, 47.7 years) and 2,188 older women (mean age, 74.4 years), who lived in 47 prefectures in Japan, provided data on their education (low, middle, and high) and dietary intakes from a diet history questionnaire. A diet quality score (possible score 0–70) was calculated based on seven food components. Mean diet quality scores, with adjustment for lifestyle and neighborhood variables, were estimated by education using a general linear model, and Dunnett’s multiple comparison was conducted. Additionally, mean scores of each food component were estimated by education and compared using the same manner.

Results

After adjustment for lifestyle and neighborhood variables, mean diet quality score of high or middle education was higher than low education for both generations. Middle-aged women with high and middle education had higher scores of ‘milk’, ‘snacks, confection, and beverages’, ‘fruits’, and ‘vegetable dishes’ than those with low education. Older women with high and middle education had higher scores of ‘sodium from seasonings’ and ‘fruits’ than those with low education.

Conclusions

This study suggests that positive associations between education and diet quality are explained by different food groups in middle-aged and older Japanese women, which are independent of lifestyle and neighborhood variables.