We aim to determine the association between Fe status and the metabolic syndrome (MetS) during menopause. Records of 1069 premenopausal and 703 postmenopausal Korean women were retrieved from the database of the fifth Korean National Health and Nutrition Examination Survey (KNHANES V 2012) and analysed. The association between the MetS and Fe status was performed using multivariable-adjusted analyses, subsequently develop a prediction model for the MetS by margin effects. We found that the risk of Fe depletion among postmenopausal women was lower than premenopausal women (PR = 0·813, 95 % CI 0·668, 0·998, P = 0·038). The risk of the MetS was 2·562-fold lower among premenopausal women with than without Fe depletion (PR = 0·390, 95 % CI 0·266, 0·571, P < 0·001). In contrast, the risk of the MetS tended to be higher among postmenopausal women with than without Fe depletion (PR = 1·849, 95 % CI 1·406, 2·432, P < 0·001). When the serum ferritin levels increased, the risk of the MetS increased in both premenopausal women and postmenopausal women. The margin effects showed that an increase in serum Hb and ferritin was associated with an increase in the risk of the MetS according to menopausal status and age group. Therefore, ferritin is the most validated and widely used Fe marker, could be a potential clinical value in predicting and monitoring the MetS during menopause. Further prospective or longitudinal studies, especially, clinically related studies on menopause and Fe status, are needed to clarify the causality between serum ferritin levels and the MetS that could offer novel treatments for the MetS.

Healthy dietary habits reduce the likelihood for the metabolic syndrome (MS). The present study investigated whether awareness of nutrition information is associated with a decreased likelihood for the MS after adjusting for potential confounders among Korean adults aged 20 years and older. Data were obtained from the Korean National Health and Nutrition Examination Survey 2016–2018. Of the 14 490 participants, 4001 (27·6 %) participants had the MS. In total, 3815 (26·3 %) participants checked nutritional facts and made labelling-dependent purchasing decisions (aware + consider), 7001 (48·3 %) checked nutritional facts but did not make labelling-dependent purchasing decisions or were aware of nutrition facts but did not check them when making food purchasing decisions (aware + not consider) and 3674 (25·4 %) were unaware of nutritional facts (not aware). The aware + consider group was less likely to develop the MS than other groups. The aware + not consider, and not aware groups were at higher association with the MS compared with the aware + consider group. Statistically significant associations were observed between the MS and several demographic characteristics including sex, age, household income, education level, employment status, public health insurance status, smoking status, alcohol consumption and aerobic exercise.

Diet may play an important role in breast cancer recurrence or survival, and therefore assessment of long-term diet among breast cancer survivors is important in breast cancer survivorship research. Given that the diet of breast cancer survivors may differ from that of the general population, the use of a FFQ specific to this group may be needed. The objective of this study was to develop a FFQ for breast cancer survivors, the most commonly used tool to measure long-term dietary patterns in nutritional epidemiological studies. We collected information on the foods and amounts of foods consumed using 3-d dietary records from a total of 192 women who had been diagnosed with stage I–III breast cancers and had undergone breast cancer surgery at least 6 months before the baseline study. A total of 1254 foods and dishes consumed were re-grouped by the similarity of the main ingredients and/or serving units, and several dishes commonly consumed among the Korean population were added. After we performed contribution analyses and variability analyses to detect between-person variation for selected nutrients, we listed a total of 123 foods and dishes for the FFQ specific to breast cancer survivors. Our breast cancer survivor-specific FFQ can be used to estimate long-term dietary intake and to examine its association with breast cancer prognosis in epidemiological studies of breast cancer in Korea.

Research on the effect of low-fat intake on hearing is limited. This study aimed to elucidate the relationship between fat, carbohydrate and protein intake and the presence of hearing discomfort among the elderly. The Korean National Health and Nutrition Examination Survey was conducted from 2009 through to 2012. A total of 4615 participants ranging in age from 60 to 80 years underwent a pure-tone audiometric evaluation, a physical examination and a nutritional survey. The associations between the participants’ hearing thresholds and their protein/fat/carbohydrate intake/total energy intake were analysed using simple and multiple regression models with complex sampling adjusted for confounding factors, such as BMI, income level, smoking status and a history of hypertension, hyperlipidaemia and diabetes. Low fat and protein intakes were associated with hearing discomfort (OR 0·82, 95 % CI 0·71, 0·96, P=0·011; OR 0·81, 95 % CI 0·67, 0·96, P=0·017, respectively). This study revealed that low fat and protein intakes are associated with hearing discomfort in the elderly Korean population.

The frequency of dining out has rapidly increased; however, the independent associations between dining out, metabolic syndrome risk factors and nutritional status have not been well characterised. The aim of the present study was to investigate the associations between dining out, nutritional intakes and metabolic syndrome risk factors among Korean adults, using data from the 2011 Korean National Health and Nutrition Examination Survey. Frequency of dining out was significantly associated with intake of nutrients such as energy, water, protein, fat, carbohydrate, Ca, Na, vitamin A and carotene. Especially, the result revealed that Korean adults had insufficient Ca intake compared with the Korean reference intake (700 mg). As the frequency of dining out increased, so did energy intake. In addition, individuals who dined out seven or more times per week experienced a 64 % higher likelihood of blood pressure abnormalities, an 88 % higher likelihood of waist circumference abnormalities, and a 32 % higher likelihood of low HDL-cholesterol levels than those who dined out less than once per week. BMI was not associated with the frequency of dining out. Our findings suggest that strategies to modify dining-out behaviour could reduce metabolic syndrome risk factors via improved nutrition.

The purpose of the present study was to analyse vegetable intake by the Korean population based on different meal formats. Twenty-four-hour dietary recall data from the Korean National Health and Nutrition Examination Survey were used to assess daily vegetable intake and consumption ratio of vegetables for different meal types/dining locations. Analysis was stratified by sex and age group. Daily vegetable intake increased from 293·5 g in 1998 to 305·7 g in 2001 and to 335·9 g in 2005. Findings were similar in men and women, as well as in each age group. Analyses for each meal type revealed that vegetable intake during breakfast did not substantially change, but vegetable intake increased during lunch and dinner. While vegetable consumption ratio during breakfast decreased, it increased during lunch and snack time. Men and women showed similar change in the analysis for meal types and dining locations. There were some differences between the age groups in daily vegetable intake depending on the meal type. Another notable observation was the increasing change of vegetable intake during lunch and during meals eaten at cafeterias and restaurants in all the age groups. Analysis of vegetable consumption ratio showed an increased consumption in cafeterias, restaurants, and other places and decreased vegetable intake at home for those aged 16–64 years with time. Since this change may be related to improvements in socioeconomic status, it will be necessary to further investigate difference in vegetable intake based on socioeconomic levels within the population.

The purpose of the present study was to test the usefulness of dish items selected in developing a dish-based FFQ (DFFQ) to be used for epidemiological studies in Korea. The dietary data of 6817 subjects from the 2001 Korean National Health and Nutrition Examination Survey were used for the analysis. The 24 h recall method was employed for the dietary survey. Initially, ninety-five dish items were selected in developing the DFFQ based on consumption frequency, contribution of selected nutrients and coverage of between-person variations. The usefulness of the selected ninety-five dish items was tested based on their degree of contribution in supplying nutrients in the cumulative percentage contribution (cPC), as well as on their degree of explanation for between-person variation in the cumulative regression coefficient (cMRC). According to the results, the ninety-five selected dish items accounted for an average of 92·3 % of seventeen nutrients consumed by the study subjects based on cPC estimation. The top twenty items among the ninety-five dish items covered 70 to 91 % of the between-person variation for the seventeen nutrients based on cMRC estimation. Thus, the results suggest that the ninety-five items would be useful in developing a FFQ for use in epidemiological studies of Koreans, within less than 10 % underestimation.