Hae-Jeung Lee

Dietary sodium intake and prevalence of overweight in adults

OBJECTIVE There has been no convincing evidence for a direct relation between sodium intake and being overweight. Therefore, we investigated the independent relationship between overweight and sodium intake in human subjects. METHODS Of those aged 19 to 64 years who participated in the 4th Korea National Health and Nutrition Examination Survey, a total of 5955 participants (54% female) were included. Subjects were excluded if they reported unrealistic daily total energy intakes or intentional dietary changes, were pregnant, or were diagnosed with hypertension, diabetes, renal failure, liver cirrhosis, or thyroid disease. Overweight was defined as having a body mass index of 25 kg/m(2) or higher. Sodium intake was calculated from 24-h recall and categorized into quintiles. Multivariate logistic regression was used to test the relationship between sodium intake and being overweight. RESULTS Compared to men in the lowest quintile, men in the 4th and 5th quintiles had an increased risk of being overweight with odds ratios (ORs) of 1.37 (95% confidence interval [CI], 1.02-1.82) and 1.67 (95% CI, 1.23-2.27) respectively, after adjusting for confounding factors including soft drink and energy intake. The P value for trend of ORs in each quintile for men was 0.0033. In women, compared to the lowest quintile, the highest quintile had an OR of 1.31(95% CI, 0.96-1.79) and showed a marginally significant trend towards increasing risk of being overweight (P value=.058). CONCLUSIONS Our findings suggest an independent relationship between high sodium intake and an increased risk of being overweight in adults.

Intakes of Dairy Products and Calcium and Obesity in Korean Adults: Korean National Health and Nutrition Examination Surveys (KNHANES) 2007-2009

Background The possible effects of dairy product intake against obesity have been suggested in animal studies; however, the association is still not well established in epidemiological studies. Few studies in Asian countries with relatively low intake of dairy products exist. Objective We investigated the association between dairy products and calcium intake and obesity in Korean population with relatively low intake of dairy products. Subjects and Methods Our study population consisted of adults (n = 7173) aged 19–64 among participants of the 2007, 2008 and 2009 Korean National Health and Nutrition Examination Survey who had not made any attempt of intentional weight loss. Dietary intake data from food frequency questionnaire (FFQ) and 24-hour recall were used. Dairy products included milk and yogurt in the FFQ. Obesity was defined as BMI≥25 kg/m2. Results Higher frequency of dairy product intake was associated with a reduced prevalence of obesity (OR = 0.63; 95% CI = 0.45–0.89 for ≥2 times/day vs. ≤1 time/month; p for trend = 0.003) using the intake data from FFQ. Similarly, high frequency of milk or yogurt intake had an inverse association with obesity. The association between milk and yogurt intake and obesity was similar when the intake from 24-hour recall was examined. Higher calcium intake from dairy products as well as total dietary calcium intake was associated with a decreased prevalence of obesity (OR = 0.83; 95% CI = 0.71–0.98 for highest vs. lowest quintile of dairy calcium intake; p for trend = 0.02, OR = 0.78; 95% CI = 0.64–0.94 for highest vs. lowest quintile of total calcium intake; p for trend = 0.04). The associations appeared to be stronger in women than in men. Conclusion These results suggest that high consumption of dairy products is associated with a lower prevalence of obesity and that calcium in dairy products may be one of the components contributing to the association. Further longitudinal studies are warranted to replicate our findings.

Gender and Socioeconomic Status in Relation to Weight Perception and Weight Control Behavior in Korean Adults

Aim: In Korea, obesity is more prevalent among men and lower socioeconomic groups. To explain this obesity disparity, we compared weight perception and weight control behavior across gender and socioeconomic status (SES). Methods: We analyzed data from 16,260 participants aged 20 years or older in a nationally representative cross-sectional survey. SES indicators included education and income levels. Weight under-perception was defined when participants considered themselves lighter than their measured BMI status. Either no active or inappropriate weight control (i.e., trying to gain weight in obese individuals) was considered to be unhealthy patterns. Multivariate prevalence ratios were calculated using log-binomial regressions. Results: Men had a higher prevalence of weight under-perception (24.5 vs. 11.9%) and unhealthy patterns of weight control behavior (57 vs. 40%) than women. Low education level was associated with weight under-perception (ptrend = 0.022 in men, ptrend < 0.001 in women). Both education and income levels were significantly associated with patterns of weight control behavior (for education: ptrend < 0.001 in men and women; for income: ptrend = 0.047 in men, ptrend < 0.001 in women). Conclusion: Weight perception and weight control behavior significantly varied by gender and SES. Public actions should be directed toward improving perception and behavior of high-risk populations.

The association between disturbed eating behavior and socioeconomic status: the Online Korean Adolescent Panel Survey (OnKAPS).

Background A limited amount of research, primarily conducted in Western countries, has suggested that higher socioeconomic status (SES) is associated with higher risk of eating disorders (EDs). However, little is known about this association in Asian countries. We examined the association of SES with disturbed eating behavior (DEB) and related factors in Korean adolescents. Subjects A nationwide online panel survey was conducted in a sample of adolescents (n = 6,943, 49.9% girls). DEB was measured with the 26-item Eating Attitudes Test (EAT-26). Participants who scored ≥20 on the EAT-26 were considered to have DEB. Participants’ SES was determined based on self-reported household economic status. Results The prevalence of DEB was 12.7%: 10.5% among boys and 14.8% among girls. Both boys and girls with DEB were more likely to perceive themselves as obese, experience higher levels of stress, and have lower academic achievement. The risk for DEB was significantly higher in boys of higher SES than in those of middle SES (OR = 1.45, 95%CI = 1.05–1.99 for high SES; OR = 5.16, 95%CI: 3.50–7.61 for highest SES). Among girls, higher risk of DEB was associated with the highest and lowest SES (OR = 1.52, 95%CI: 1.13–2.06 for lowest SES; OR = 2.22, 95%CI: 1.34–3.68 for highest SES). Conclusions Despite the lower prevalence of obesity in Korea compared with Western countries, the prevalence of DEB in Korean adolescents was high, especially among girls. Moreover, the association between SES and DEB followed a U-shaped curve for girls and a J-shaped curve for boys.

Weight misperception and its association with dieting methods and eating behaviors in South Korean adolescents.

BACKGROUND/OBJECTIVES There is little information on the association between weight misperception and eating behavior in Korean adolescents. Therefore, we investigated the association of food intake habits and dieting method and disturbed eating behavior (DEB) in relation to weight misperception. SUBJECTS/METHODS Data was collected by using a nationwide online panel survey from 6,943 adolescents enrolled in middle/high school. DEB was measured with the Eating Attitudes Test (EAT-26) and those who scored ≥ 20 on the EAT-26 were considered to have eating disorder. Logistic regressions were conducted to examine the association between weight misperception based on self-reported weight status and dieting method and eating behaviors. RESULTS The proportion of weight underestimation was 23.5% and that of overestimation was 24.0%. Weight overestimating girls were more likely to engage in various unhealthy dieting practices (OR = 1.69 for fasting; OR = 1.88 for laxative or diuretic use; OR = 2.05 for self-induced vomiting after meals; P < 0.05). Moreover, there was a strong association between overestimation and undesirable eating behaviors, especially among girls, e.g.: having breakfast (OR = 0.85), high consumption of fast foods (OR = 1.28) and regular sodas (OR = 1.39), but not among boys. In both genders, weight overestimation appears to be a major risk factor for DEB (OR = 1.34 for boys and OR = 1.41 for girls; P < 0.05). CONSLUSIONS Weight overestimation is associated with unhealthy weight control practices and eating behaviors. We particularly found a significant association between weight overestimation and DEB among nationwide Korean adolescents.

Associations between Sugar Intake from Different Food Sources and Adiposity or Cardio-Metabolic Risk in Childhood and Adolescence: The Korean Child–Adolescent Cohort Study

The increasing prevalence of childhood obesity is a serious public health problem associated with co-morbidities in adulthood, as well as childhood. This study was conducted to identify associations between total sugar intake and sugar intake from different foods (fruit, milk, and sugar-sweetened beverages (SSBs)), and adiposity and continuous metabolic syndrome scores (cMetS) among Korean children and adolescents using cohort data. The study subjects were children (n = 770) who participated in the 4th year (2008) of the Korean Child–Adolescent Cohort Study (KoCAS). Dietary intake data were collected via three-day 24-h food records, and sugar intake was calculated for the total sugar content of foods using our database compiled from various sources. Anthropometric measurements, assessments of body composition, and blood sample analysis were performed at baseline and at follow-up four years later. The cMetS was calculated based on waist circumference, triglycerides, high-density lipoprotein cholesterol, glucose, and mean arterial blood pressure. According to multiple linear regression analysis, there were no significant associations between total sugar intake and adiposity and cMetS. However, higher intake of fruit sugar at baseline was significantly associated with lower body mass index (BMI) z-scores and body fat percentages at baseline (β = −0.10, p = 0.02 and β = −0.78, p < 0.01, respectively). At follow-up, sugar intake from fruit at baseline was still negatively associated with the above outcomes, but only the relationship with BMI z-scores retained statistical significance (β = −0.08, p < 0.05). There was a significant positive relationship between consumption of sugar from SSBs and cMetS at baseline (β = 0.04, p = 0.02), but that relationship was not observed at follow-up (p = 0.83). Differences in consumption sugars from fruit and SSBs might play an important role in the risk of adiposity and metabolic disease in children and adolescents. Our results suggest that strategies for reducing sugar intake need to target particular food groups. Consequently, this information could be of value to obesity- and metabolic disease-prevention strategies.

Polymorphisms in Xenobiotic Metabolizing Genes, Intakes of Heterocyclic Amines and Red Meat, and Postmenopausal Breast Cancer

Heterocyclic amines (HCAs) are mutagenic compounds generated when meats are cooked at high temperature and for long duration. The findings from previous studies on the relation between HCAs and breast cancer are inconsistent, possibly because of genetic variations in the enzymes metabolizing HCAs. To evaluate whether the associations of intakes of estimated HCAs, meat-derived mutagenicity (MDM), and red meat with risk of postmenopausal breast cancer were modified by N-acetyltransferase 2 (NAT2) acetylator genotype or cytochrome P450 1A2-164 A/C (CYP1A2) polymorphism, we conducted a nested case-control study with 579 cases and 981 controls within a prospective cohort, the Nurses’ Health Study. HCAs and MDM intakes were derived using a cooking method questionnaire administered in 1996. NAT2acetylator genotype, the CYP1A2 polymorphism, and intakes of HCAs, MDM, and red meat were not associated with risk of postmenopausal breast cancer. There was also no interaction between NAT2 acetylator genotype or CYP1A2 polymorphism and HCAs and MDM and red meat intake in relation to breast cancer. These results do not support the hypothesis that genetic polymorphisms of xenobiotic enzymes involved in the metabolism of HCAs may modify the associations between intakes of red meat or meat-related mutagens and breast cancer risk.

Protective effect of lanostane triterpenoids from the sclerotia of Poria cocos Wolf against cisplatin-induced apoptosis in LLC-PK1 cells

Cisplatin-induced nephrotoxicity is a serious adverse effect that limits the use of cisplatin in cancer patients. In the present study, we investigated the protective effect of lanostane triterpenoids (1-10) isolated from the ethanolic extract of Poria cocos Wolf against cisplatin-induced cell death in LLC-PK1 kidney tubular epithelial cells. Treatment of cisplatin induced significant cell death, which was suppressed by treatment with dehydroeburicoic acid monoacetate (1) and 3β-acetoxylanosta-7,9(11),24-trien-21-oic acid (9). Compound 1 exhibited the highest efficacy among the tested compounds and was thus subjected to further mechanistic studies. The increase in the percentage of apoptotic cells induced by cisplatin reduced by 4.3% after co-treatment of cells with compound 1 (50 and 100μM). Furthermore, phosphorylation of the mitogen-activated protein kinases JNK, ERK, and p38, and caspase-3, which characterize oxidative stress-mediated apoptosis, increased significantly after treatment with cisplatin, and decreased after treatment with compound 1. These results indicate that the renoprotective effects of compound 1 may be mediated by its anti-apoptotic activity.

Gender differences in the relationship between risk of hypertension and fruit intake

OBJECTIVE To investigate the relationship between hypertension and fruit intake in an Asian population. METHOD This study was based on the data from 2007, 2008 and 2009 Korea National Health and Nutrition Examination Survey. In the final analysis, a total of 9791 subjects (men=3819, women=5972) were included. Daily energy and nutrient intakes were assessed using 24-h recall. The odds ratios (ORs) for hypertension were assessed by using logistic regression and multivariable models. RESULTS A total of 10.6% of individuals were classified as having hypertension. Compared with the lowest quintile of fruit intake, the fifth quintile showed the lowest likelihood of hypertension (OR 0.73; 95% confidence interval [CI], 0.61-0.88) after adjusting for age and gender. For women, the likelihood of hypertension in the 2nd, 3rd, 4th and 5th quintiles of fruit intake decreased to 0.67 (95% CI, 0.34-1.30), 0.76 (0.56-1.05), 0.90 (0.67-1.22) and 0.54 (0.38-0.77), respectively, after adjusting for confounding factors (P value for trend=0.0011). An inverse association of fruit intake and hypertension was shown only in non-obese women. For men and obese women, there was no relationship between fruit intake and hypertension. CONCLUSION Dietary fruit recommendation for hypertension should be taken into account together with ethnic background, gender as well as the presence of obesity in individuals.

Anti-Inflammatory Phenolic Metabolites from the Edible Fungus Phellinus baumii in LPS-Stimulated RAW264.7 Cells

The edible fungus Phellinus baumii Pilat (Hymenochaetaceae) has been used in Korean traditional medicines for strengthening health and prolonging life. An extract of the fruiting bodies of P. baumii was subjected to bioassay-guided fractionation based on its anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The resulting fractions were chemically investigated, leading to isolation of three phenolic compounds (1–3), a sesquiterpene (4), two steroids (5–6), a fatty acid (7), and a cerebroside (8). Spectroscopic analyses including 1D and 2D NMR spectroscopy and LC/MS were used to determine their chemical structures. Compounds 2, 4, 5, 7 and 8 were identified in P. baumii for the first time. Since all compounds were isolated from active fractions with anti-inflammatory activity, their ability to inhibit LPS-stimulated nitric oxide (NO) production in RAW264.7 cells were evaluated in vitro. Compounds 1, 2, 3, 5 and 7 inhibited LPS-stimulated NO production, and compounds 1–3 had IC50 values <10 μM. Treatment of LPS-stimulated RAW264.7 cells with compounds 1–3 inhibited phosphorylation of IKKα and IκBα. In addition, treatment of compounds 1–3 reduced LPS-induced increases of nuclear factor-kappa B (NF-κB) p65, iNOS and COX-2 protein expressions. Collectively, compounds 1–3 inhibited NF-κB-dependent inflammation in RAW264.7 cells. Thus, P. baumii is a potential source of natural anti-inflammatory agents, and active compounds 1–3 could be promising lead compounds for the development of novel anti-inflammatory agents.