A modified Mediterranean diet score is inversely associated with metabolic syndrome in Korean adults

Adherence to the Mediterranean diet and allergic diseases in Korean adults: KNHANES 2013-2016

Background

The prevalence of allergic diseases [e.g., asthma, allergic rhinitis (AR), atopic dermatitis (AD)] has increased significantly in recent years, which is coincides with a shift in modern eating habits. The Mediterranean diet, due to its anti-inflammatory properties, may be beneficial in the prevention of allergic diseases. However, its effects on allergic diseases have not been sufficiently studied. We investigated the relationship between adherence to the Mediterranean diet and allergic diseases.

Methods

This study analyzed the relationship between adherence to the Mediterranean diet (using the modified Mediterranean diet score, mMED) and atopic dermatitis, asthma, and allergic rhinitis in 12,080 participants using data from the 2013-2016 Korean National Health and Nutrition Examination Survey (KNHANES). Multiple logistic regression analyses were used to control for confounding factors such as age, gender, education level, income, and lifestyle.

Results

In multivariable adjusted models, participants with higher mMED had a significantly lower risk of developing AD (OR 0.57; 95% CI, 0.36-0.92; p trend = 0.0201). When stratified by sex, this risk reduction was more significant in females (OR 0.50; 95% CI, 0.27-0.96; p trend <0.05). Across mMED components, fish and peanut intake were negatively associated with the occurrence of AD and AR (OR 0.55; 95% CI, 0.40-0.76; p trend <0.05, OR 0.75; 95% CI, 0.65-0.87; p trend <0.05). There was no significant association between asthma and AR and mMED scores.

Conclusion

High adherence to the Mediterranean diet is associated with a lower prevalence of atopic dermatitis, especially in women. Fish and peanut intake have an important protective role against atopic diseases.

Nutritional Barriers to the Adherence to the Mediterranean Diet in Non-Mediterranean Populations

Adherence to the Mediterranean diet has been shown to lower the risk of developing chronic non-communicable diseases like cardiovascular and neurodegenerative diseases and cancer. Improvements in depression, participation in daily activities in older individuals, weight loss and a reduction in adverse pregnancy outcomes are associated with adherence to the Mediterranean diet. The number of studies that have evaluated barriers to adherence to the Mediterranean diet in the US and, in particular, in racial and ethnic minority populations within the US are few. Among Native American and Alaskan Native populations, studies evaluating traditional or alternative Mediterranean diet adherence for chronic non-infectious diseases is unavailable. Mediterranean diet scoring instruments used in studies in European and Mediterranean countries and among white participants in the US fail to capture the dietary patterns of racial and ethnic minority populations. In this narrative review, the food components of the traditional Mediterranean diet are discussed, adherence to the Mediterranean diet is examined in Mediterranean and non-Mediterranean countries and barriers preventing adherence to the Mediterranean diet in the US and among racial and ethnic minority populations is reviewed. Recommendations for improving nutrition education and intervention and for increasing adherence and cultural adaptions to the Mediterranean diet are provided.

Adherence to a Mediterranean type of diet in the world: a geographical analysis based on a systematic review of 57 studies with 1,125,560 participants

This systematic review aimed to assess the level and time-trends of adherence to Mediterranean-type diets (MTD) among the general population, globally. According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses, a comprehensive literature search of the MEDLINE and Scopus databases was carried out, until 04/09/2023, based on specific criteria. Fifty-seven studies with 1,125,560 apparently healthy adults from Europe (n = 37), US (n = 8), Asia (n = 8), Australia (n = 4) and Africa (n = 1) were included. Adherence to an MTD was moderate with a significant decline observed in the last decade. European countries, mainly driven by Mediterranean countries, showed higher adherence than other regions. Geographical analysis revealed that adherence to an MTD is related to both geographic location and socioeconomic status throughout the world.

Relationship between Mediterranean diet and depression in South Korea: the Korea National Health and Nutrition Examination Survey

Background

Several studies have shown that adherence to the Mediterranean diet is associated with a lower risk of depression; however, little is known about the Asian population. This study investigated the relationship between adherence to the Mediterranean diet and depression in a sample of the South Korean population.

Methods

In total, 5,849 adults from the 2014 and 2016 Korea National Health and Nutrition Examination Surveys were included in the study. The Mediterranean diet adherence was measured using a modified alternate Mediterranean diet score (mMED) developed to adjust for Korean dietary patterns. The mMED scores using the Food Frequency Questionnaire were divided into four categories (0-2, 3-4, 5-6, and 7-9 points). Subjects with depression were defined as having moderate-to-severe depressive symptoms using the Patient Health Questionnaire-9, with a cutoff value of 10. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). A subgroup analysis was performed based on sex.

Results

The results of logistic regression analysis indicated that individuals with higher mMED were 42-73% less likely to report depression compared to individuals with the lowest mMED [ORs (95% CIs) =0.58 (0.37-0.90), 0.50 (0.31-0.80), 0.27 (0.15-0.47)] after adjusting for socio-demographic and health-related variables. In women, individuals with mMED of 7-9 had 71% lower odds of depression [ORs (95% CIs): 0.29 (0.13-0.64)]. In men, individuals with mMED of 5-9 had 55% [ORs (95% CIs): 0.45 (0.23-0.91)] to 79% [ORs (95% CIs): 0.21 (0.08-0.57)] lower odds of depression.

Conclusion

This study suggests that adherence to the Mediterranean diet is inversely associated with depression in both men and women among Korean adults. This study provides evidence that a Mediterranean diet is crucial in preventing depressive symptoms in Asian populations.

Reproducibility of a food frequency questionnaire: Korea Nurses' Health Study

BACKGROUND/OBJECTIVES

This study aimed to examine the reproducibility of food frequency questionnaires (FFQs) designed for young female nurses in the Korea Nurses' Health Study.

SUBJECTS/METHODS

The reproducibility of web-based, self-administered FFQs was evaluated among 243 Korean female nurses. The first FFQ (FFQ1) was administered from March 2014 to February 2019 and the second FFQ (FFQ2) from November 2019, with a mean interval of 2.8 years between the FFQs (range, 9 months–5.6 years). Pearson and Spearman correlation coefficients (r values) and quartile agreements between FFQ1 and FFQ2 were calculated for intakes of energy, nutrients, and foods.

RESULTS

Pearson correlation coefficients ranged from 0.41 to 0.55 (median r = 0.51) for energy and raw nutrients and from 0.16 to 0.46 (median r = 0.36) for energy-adjusted nutrients. Spearman correlation coefficients ranged from 0.25 to 0.72 (median r = 0.41) for food items. The percentages of women who were classified into the same or adjacent quartile were 77% to 84% (median = 82%) for raw nutrients and 69% to 86% (median = 78%) for foods.

CONCLUSIONS

The results indicated that the web-based FFQ used in the Korea Nurses' Health Study has acceptable reproducibility.

Mediterranean diet scoring systems: understanding the evolution and applications for Mediterranean and non-Mediterranean countries

The Mediterranean diet (MedD) is a flexible dietary pattern which has such variability that has led to inconsistencies in definitions and assessment. The purpose of this narrative review is to evaluate scoring systems in a cultural and geographic context, from Mediterranean and non-Mediterranean countries, for comparison and application. The early MedD scoring systems (i.e. Trichopoulou's MedD Scale (T-MDS) and alternative MedD Scale (aMed)) are widely applied throughout the world but use population-specific median cut-offs which limit interpretation and cross-study comparisons. The T-MDS and aMed also do not account for non-traditional MedD foods which are consumed in greater quantities than when the scoring systems were developed. Scoring systems developed after the MedD pyramid publication in 2011 have generally used these recommendations as a basis for food group intake cut-offs, incorporating more foods/food groups as negative components, and some have included dietary and lifestyle behaviours. The different approaches to MedD assessment have created much variability in the foods/food group components included in scoring systems. Assessments that include dietary and lifestyle behaviours may reflect the nutrition transition occurring in Mediterranean countries and better guide clinical intervention approaches. While the new scoring systems are theorised to better capture MedD adherence and behaviours, comparisons are sparse in the literature and none exists outside of Europe. Consensus on food and dietary behaviours to include as well as the methodology for assigning points in MedD scoring systems is needed to advance our understanding of MedD and health relationships to promote public health messaging and clinical application.

Impact of the Level of Adherence to Mediterranean Diet on the Parameters of Metabolic Syndrome: A Systematic Review and Meta-Analysis of Observational Studies

High adherence to the Mediterranean diet (MD) has been associated with a lower prevalence of Metabolic Syndrome (MetS). The present study aimed to investigate the impact of MD adherence on parameters of MetS. A systematic literature search was performed in PubMed, Cochrane Central Registry of Clinical Trials (CENTRAL), Scopus, EMBASE, Web of Science and Google Scholar databases. Observational studies that recorded adherence to MD and components/measures of the MetS, such as waist circumference (WC), blood pressure (BP), fasting blood glucose (FBG), high-density lipoprotein (HDL) cholesterol and triglycerides (TG), were included in this study. A total of 58 studies were included in our study. WC and TG were significantly lower in the high adherence MD group (SMD: -0.20, (95%CI: -0.40, -0.01), SMD: -0.27 (95%CI: -0.27, -0.11), respectively), while HDL cholesterol was significantly higher in the same group (SMD: -0.28 (95%CI: 0.07, 0.50). There was no difference in FBG and SBP among the two groups (SMD: -0.21 (95%CI: -0.54, 0.12) & SMD: -0.15 (95%CI: -0.38, 0.07), respectively). MD may have a positive impact on all parameters of MetS. However, further research is needed in this field.

Relationship between Dietary Patterns and Cardiovascular Disease Risk in Korean Older Adults

OBJECTIVES

The purpose of this study was to assess the relationship between dietary patterns and the 10-year risk of cardiovascular disease (CVD) in the elderly population in Korea.

METHODS

Cluster analysis was conducted on the data of 1687 elderly participants (797 men and 890 women) aged ≥65 years from the 2014-2016 Korea National Health and Nutrition Examination Survey (KNHANES), using a 24-h dietary recall survey to assess dietary patterns. Dietary patterns were classified into clusters 1 (typical Korean diet), 2 (high carbohydrate diet), and 3 (healthy diet). The 10-year risk of CVD was calculated based on age, total and HDL-cholesterol levels, systolic blood pressure level, antihypertensive medication use, smoking status, and presence of diabetes. A complex sample general linear model was applied to determine the association between dietary patterns and the 10-year risk of CVD.

RESULTS

In total, 275 (33.7%), 141 (17.9%), and 381 (48.3%) men, and 207 (22.6%), 276 (30.9%), and 407(46.6%) women were included in clusters 1, 2, and 3, respectively. The 10-year risk of CVD was lower in men in cluster 3 (healthy diet) than in those in cluster 1 (typical Korean diet) (t = 2.092, p = 0.037). Additionally, the 10-year risk of CVD was lower in men who performed strength training than in those who did not (t = 3.575, p < 0.001). There were no significant differences in women.

CONCLUSIONS

After adjusting for sociodemographic variables, men who consumed a healthy diet had a lower 10-year risk of CVD than those who consumed a typical Korean diet. When organizing nutrition education programs to improve dietary habits in the elderly, content on diets that consist of various food groups to prevent CVD is required. In particular, it is necessary to develop content that emphasizes the importance of healthy eating habits in men.

Development, validation and utilisation of dish-based dietary assessment tools: a scoping review

OBJECTIVE

To summarise the existing evidence of development, validation and current status of utilisation of dish-based dietary assessment tools.

DESIGN

Scoping review.

SETTING

Systematic search using PubMed and Web of Science.

RESULTS

We identified twelve tools from seventy-four eligible publications. They were developed for Koreans (n 4), Bangladeshis (n 2), Iranians (n 1), Indians/Malays/Chinese (n 1), Japanese (n 3) and Chinese Americans (n 1). Most tools (10/12) were composed of a dish-based FFQ. Although the development process of a dish list varied among the tools, six studies classified mixed dishes based on the similarity of their characteristics such as food ingredients and cooking methods. Tools were validated against self-reported dietary information (n 9) and concentration biomarkers (n 1). In the eight studies assessing the differences between the tool and a reference, the mean (or median) intake of energy significantly differed in five studies, and 26-83 % of nutrients significantly differed in eight studies. Correlation coefficients for energy ranged from 0·15 to 0·87 across the thirteen studies, and the median correlation coefficients for nutrients ranged from 0·12 to 0·77. Dish-based dietary assessment tools were used in fifty-nine studies mainly to assess diet-disease relationships in target populations.

CONCLUSIONS

Dish-based dietary assessment tools have exclusively been developed and used for Asian-origin populations. Further validation studies, particularly biomarker-based studies, are needed to assess the applicability of tools.

Dietary Strategies for Metabolic Syndrome: A Comprehensive Review

Metabolic syndrome is a cluster of metabolic risk factors, characterized by abdominal obesity, dyslipidemia, low levels of high-density lipoprotein cholesterol (HDL-c), hypertension, and insulin resistance. Lifestyle modifications, especially dietary habits, are the main therapeutic strategy for the treatment and management of metabolic syndrome, but the most effective dietary pattern for its management has not been established. Specific dietary modifications, such as improving the quality of the foods or changing macronutrient distribution, showed beneficial effects on metabolic syndrome conditions and individual parameters. On comparing low-fat and restricted diets, the scientific evidence supports the use of the Mediterranean Dietary Approaches to Stop Hypertension (DASH) diet intervention as the new paradigm for metabolic syndrome prevention and treatment. The nutritional distribution and quality of these healthy diets allows health professionals to provide easy-to-follow dietary advice without the need for restricted diets. Nonetheless, energy-restricted dietary patterns and improvements in physical activity are crucial to improve the metabolic disturbances observed in metabolic syndrome patients.

East Asian diet-mimicking diet plan based on the Mediterranean diet and the Dietary Approaches to Stop Hypertension diet in adults with type 2 diabetes: A randomized controlled trial

Aims/Introduction

Using an investigational diet plan based on the Mediterranean diet and the Dietary Approaches to Stop Hypertension diet comprised of substitute ingredients that mimic the average East Asian diet, this study assessed the glycemic benefits in comparison with a food exchange system‐based diet in established type 2 diabetes patients.

Materials and Methods

This was a 12‐week, open‐label randomized clinical trial carried out among 60 Korean adults with type 2 diabetes having a median body mass index of 23.5 kg/m². Glycemic benefits in the investigational diet (group A) were compared with those obtained with a food exchange system‐based diet, either in the form of ready meals provided to participants (group B) or not (group C). The primary end‐point was changes in glycated hemoglobin from baseline to week 12.

Results

Changes in glycated hemoglobin (%) from baseline to week 12 were −0.97 ± 0.97 in group A (vs group B, P = 0.085 in the full analysis set, and P = 0.028 in the per‐protocol set; vs group C, P = 0.030 in the full analysis set and P = 0.020 in the per‐protocol set), −0.51 ± 0.65 in group B (vs group C, P > 0.05 in the full analysis set and the per‐protocol set), and −0.36 ± 0.74 in group C. Decreases from baseline in body mass index, waist circumference and blood pressure were greater in group A than in group C.

Conclusion

With the provision of ready meals, the glycemic benefits of the investigational diet plan were demonstrable over a self‐prepared food exchange system‐based diet in Korean adults with established type 2 diabetes.

Development and Validation of a Questionnaire to Measure Adherence to the Mediterranean Diet in Korean Adults

The Mediterranean diet (MD) has beneficial effects on cardiovascular diseases, cancer, and mortality. Although various attempts have been made for estimating adherence to the MD using diet quality indices, few studies involving validated questionnaires for estimating adherence have been performed in Asian populations. We aimed to develop and validate the Korean version of the Mediterranean Diet Adherence Screener (K-MEDAS) by including 211 participants that visited health check-up centers and 116 participants with overweight or hypercholesterolemia that visited obesity clinic. The participants completed both the K-MEDAS and a 106-item food frequency questionnaire (FFQ). We translated 13 questions and developed 1 question. Considering the agreement between the K-MEDAS and FFQ, nine of the 14 questions showed moderate or high kappa values (≥0.4). The total MD scores measured by the K-MEDAS and FFQ showed substantial concordance (intraclass correlation coefficient = 0.678, 95% confidence interval: 0.520, 0.785). Multiple linear regression analyses revealed significant inverse associations between MD score and the levels of serum total cholesterol, low-density lipoprotein cholesterol, and non-high-density lipoprotein cholesterol, after adjusting for confounding variables. We found that K-MEDAS is valid tool for assessing adherence to the MD in the Korean population.

Associations of Dietary Intake with Cardiovascular Disease, Blood Pressure, and Lipid Profile in the Korean Population: a Systematic Review and Meta-Analysis

OBJECTIVE

Previous studies have separately reported the contributions of dietary factors to the risk of cardiovascular disease (CVD) and its markers, including blood pressure (BP) and lipid profile. This study systematically reviewed the current evidence on this issue in the Korean population.

METHODS

Sixty-two studies from PubMed and Embase were included in this meta-analysis. We performed a random-effects model to analyze pooled odds ratios (ORs) and hazard ratios (HRs) and their 95% confidence intervals (CIs) for the consumption of 14 food items, three macro- and eight micro-nutrients, two dietary patterns, and three dietary indices.

RESULTS

An analysis of pooled effect sizes from at least four individual study populations showed significant associations between coffee consumption and CVD (OR/HR, 0.71; 95% CI, 0.52-0.97) and elevated/high triglycerides (TG) (OR, 0.84; 95% CI, 0.78-0.90), sugar-sweetened beverage intake and elevated BP (OR/HR, 1.20; 95% CI, 1.09-1.33), and milk and dairy intake and elevated/high TG and low high-density lipoprotein cholesterol (HDL-C) (OR/HR, 0.82; 95% CI, 0.76-0.89 for both). Carbohydrate consumption and the low-carbohydrate-diet score were consistently related to an approximately 25% risk reduction for elevated TG and low HDL-C. A lower risk of elevated total cholesterol, but not low-density lipoprotein, was additionally observed for those with a higher low-carbohydrate-diet score. A healthy dietary pattern was only associated with a reduced risk of elevated TG in the Korea National Cancer Screenee Cohort (OR, 0.81; 95% CI, 0.67-0.98).

CONCLUSION

This study showed that milk and dairy and coffee had protective effects for CVD and its risk factors, such as BP and lipid profile, while sugar-sweetened beverages exerted harmful effects.