Interaction between vitamin E intake and a COMT gene variant on colorectal cancer risk among Korean adults: a case-control study.

OBJECTIVES: Previous human trials have not supported the anticarcinogenic effect of vitamin E despite biological plausibility and considerable epidemiological evidence. A possible explanation for this inconsistency is the interactive effect of the catechol-O-methyltransferase (COMT) gene and supplemental vitamin E on cancer. We examined whether a COMT gene variant modulates the effect of dietary vitamin E intake on colorectal cancer (CRC) risk. METHODS: In this case-control study of Korean adults (975 cases and 975 age- and sex-matched controls), dietary vitamin E density (mg/1,000 kcal) was measured using a semiquantitative food frequency questionnaire, COMT single nucleotide polymorphism (SNP) rs740603 (A>G) was genotyped, and CRC was verified histologically. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) using unconditional logistic regression models with adjustments for potential confounders. RESULTS: Higher vitamin E density was associated with a lower risk of CRC (highest vs. lowest quartiles: OR, 0.72; 95% CI, 0.55 to 0.96; p-for-trend=0.002). When stratified by COMT SNP rs740603 genotype, the inverse association between vitamin E density and CRC risk was confined to those with at least 1 A allele (≥median vs.

Coffee consumption and its interaction with the genetic variant AhR rs2066853 in colorectal cancer risk: a case-control study in Korea.

The bioactive compounds in coffee have several antioxidant properties that may beneficially impact colorectal cancer (CRC) development. The aryl hydrocarbon receptor (AhR) is an important transcription factor that regulates an enzyme related to the caffeine metabolism pathway. We investigated the modification effect on coffee of AhR gene polymorphism in the risk of CRC. A case-control study was conducted with 699 cases and 1393 controls to investigate the interaction between coffee intake and the AhR rs2066853 variant in CRC risk. The odds ratios (ORs) and 95% confidence intervals (CIs) were assessed using multiple logistic regression analyses. We observed a significant protective effect of coffee against CRC in the overall and male populations. Consuming three or more cups of coffee per day may significantly lower CRC risk in all subjects by 77% and in men by 83% (OR = 0.23, 95% CI: 0.14-0.39 and OR = 0.17, 95% CI: 0.09-0.34, respectively, P-trends < 0.001). No association between AhR rs2066853 and CRC risk was found. In the dominant model, the G/G genotype had a strongest synergistic effect with coffee on protection against CRC (OR = 0.12, 95% CI: 0.06-0.26, P-interaction = 0.014). The interaction remained significant in men and the distal colon cancer subgroup. In the additive model, the interaction was clearly shown strongest in G/G carriers (OR = 0.12, 95% CI: 0.06-0.27, P-interaction = 0.039), followed by A/A and G/A carriers. The interaction remained significant in men and the rectal cancer subgroup. In conclusion, the protective effect of coffee on CRC risk might interact with the genetic variant AhR rs2066853, and this joint effect was determined by sex and site-specific cancer.

Dietary Factors and Breast Cancer Prognosis among Breast Cancer Survivors: A Systematic Review and Meta-Analysis of Cohort Studies.

Few studies have summarized the association between dietary factors and breast cancer (BC) prognosis among breast cancer survivors (BCS). Therefore, we carried out a systematic review and meta-analysis to determine the associations between dietary factors and BC prognosis among BCS. We performed a literature search in PubMed and Embase to investigate the association between dietary factors and BC prognosis. We applied a random-effects model to compute the hazard ratio/relative risk and their 95% confidence intervals and heterogeneity (Higgins I2) and to generate forest plots using STATA. Among the 2279 papers identified, 63 cohort studies were included in the systematic review and meta-analysis. Our main finding was that higher consumption of beer and saturated fat negatively affected BC prognosis. However, the intake of lignans, fiber, multivitamins, and antioxidants was negatively associated with the risk of mortality. Furthermore, we performed subgroup analyses by menopausal status and dietary or supplementary micronutrient intake. Most trends were similar to the main findings; in particular, the vitamin C, vitamin D, and vitamin E supplements decreased the risk of mortality. This study's current systematic review and meta-analysis provide comprehensive dietary information for the development of dietary guidelines/recommendations to improve prognosis among BCS.

The Association between Coffee Consumption and Risk of Colorectal Cancer in a Korean Population.

This study was performed to investigate the association between coffee consumption and risk of colorectal cancer in a Korean population and examine whether the association can be altered by adjustment for intake of coffee additives. We conducted a case-control study involving 923 colorectal cancer cases and 1846 controls matched by sex and age (within 5 years). A semi-quantitative food frequency questionnaire was used to assess coffee intakes. High coffee consumption was associated with lower odds of developing colorectal cancer (≥3 cups/day vs. no drinks, OR = 0.68; 95% CI: 0.49-0.96). When we additionally controlled for consumption of coffee additives including sugar and cream, the inverse association became stronger (≥3 cups/day vs. no drinks, OR = 0.22; 95% CI: 0.14-0.33), and a significant inverse linear trend was shown (Ptrend < 0.0001). The inverse associations were observed for proximal (Ptrend = 0.0001) and distal (Ptrend = 0.0003) colon cancer, and rectal cancer (Ptrend < 0.0001) in the stratified analysis by anatomical sub-sites. Regarding sex, inverse associations between coffee consumption and colorectal cancer were found for men (Ptrend < 0.0001) and women (Ptrend = 0.0021). In the stratified analysis by obese status of subjects, inverse linear trends were observed in both non-obese and obese people (Ptrend < 0.0001). High coffee consumption may be associated with a lower risk of colorectal cancer in the Korean population and the degree of decrease in the odds of developing colorectal cancer changes by adjustment for intake of coffee additives.

Phytonutrient supplements and metabolic biomarkers of cardiovascular disease: An umbrella review of meta-analyses of clinical trials.

Phytonutrients exert several pharmacological effects on humans. In this study, we performed an umbrella review of the association of phytonutrient supplements (PNSs) with biomarkers of cardiovascular disease. Relevant published systematic reviews and meta-analyses of clinical trials were identified by searching PubMed, Embase, and Cochrane Library until July 4, 2020. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) for summarized effects and I2 statistics of heterogeneity were extracted from individual studies or reanalyzed using a random-effects model. Of the 50 included studies, pooled effects of PNSs on blood pressure, lipid profiles, and glycemic control were reported in 16, 25, and 14 articles, respectively. The findings appeared to be highly heterogeneous among individual trials of included systematic reviews and meta-analyses. Ginger (WMD = -6.36 mmHg, 95% CI = -11.27, -1.46) and Hibiscus sabdariffa (WMD = -7.58 mmHg, 95% CI = -9.69, -5.46) were associated with lowered systolic blood pressure, whereas Aloe vera, Nigella sativa, and spirulina were associated with beneficial effects on both lipid profiles and glycemic control. In summary, this umbrella review has provided up-to-date evidence for the effect of PNSs on biomarkers related to hypertension, dyslipidemia, and diabetes. The results must be interpreted with caution due to potential heterogeneity.

Reply to Dhawan et al. Comment on "Kim et al. The Association between Coffee Consumption and Risk of Colorectal Cancer in a Korean Population. Nutrients 2021, 13, 2753".

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All-Cause Mortality and Cardiovascular Death between Statins and Omega-3 Supplementation: A Meta-Analysis and Network Meta-Analysis from 55 Randomized Controlled Trials.

Statins and omega-3 supplementation have shown potential benefits in preventing cardiovascular disease (CVD), but their comparative effects on mortality outcomes, in addition to primary and secondary prevention and mixed population, have not been investigated. This study aimed to examine the effect of statins and omega-3 supplementation and indirectly compare the effects of statin use and omega-3 fatty acids on all-cause mortality and CVD death. We included randomized controlled trials (RCTs) from meta-analyses published until December 2019. Pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated to indirectly compare the effect of statin use versus omega-3 supplementation in a frequentist network meta-analysis. In total, 55 RCTs were included in the final analysis. Compared with placebo, statins were significantly associated with a decreased the risk of all-cause mortality (RR = 0.90, 95% CI = 0.86-0.94) and CVD death (RR = 0.86, 95% CI = 0.80-0.92), while omega-3 supplementation showed a borderline effect on all-cause mortality (RR = 0.97, 95% CI = 0.94-1.01) but were significantly associated with a reduced risk of CVD death (RR = 0.92, 95% CI = 0.87-0.98) in the meta-analysis. The network meta-analysis found that all-cause mortality was significantly different between statin use and omega-3 supplementation for overall population (RR = 0.91, 95% CI = 0.85-0.98), but borderline for primary prevention and mixed population and nonsignificant for secondary prevention. Furthermore, there were borderline differences between statin use and omega-3 supplementation in CVD death in the total population (RR = 0.92, 95% CI = 0.82-1.04) and primary prevention (RR = 0.85, 95% CI = 0.68-1.05), but nonsignificant differences in secondary prevention (RR = 0.97, 95% CI = 0.66-1.43) and mixed population (RR = 0.92, 95% CI = 0.75-1.14). To summarize, statin use might be associated with a lower risk of all-cause mortality than omega-3 supplementation. Future direct comparisons between statin use and omega-3 supplementation are required to confirm the findings.

N-6 Polyunsaturated Fatty Acids and Risk of Cancer: Accumulating Evidence from Prospective Studies.

Previous studies on the association between polyunsaturated fatty acids (PUFAs) and cancer have focused on n-3 PUFAs. To investigate the association between intake or blood levels of n-6 PUFAs and cancer, we searched the PubMed and Embase databases up to March 2020 and conducted a meta-analysis. A total of 70 articles were identified. High blood levels of n-6 PUFAs were associated with an 8% lower risk of all cancers (relative risk (RR) = 0.92; 95% confidence interval (CI): 0.86-0.98) compared to low blood levels of n-6 PUFAs. In the subgroup analyses by cancer site, type of n-6 PUFAs, and sex, the inverse associations were strong for breast cancer (RR = 0.87; 95% CI: 0.77-0.98), linoleic acid (LA) (RR = 0.91; 95% CI: 0.82-1.00), and women (RR = 0.88; 95% CI: 0.79-0.97). In the dose-response analysis, a 2% and 3% decrease in the risk of cancer was observed with a 5% increase in blood levels of n-6 PUFAs and LA, respectively. Thus, there was no significant association between n-6 PUFA intake and the risk of cancer. The pooled RR of cancer for the highest versus lowest category of n-6 PUFA intake was 1.02 (95% CI: 0.99-1.05). Evidence from prospective studies indicated that intake of n-6 PUFAs was not significantly associated with risk of cancer, but blood levels of n-6 PUFAs were inversely associated with risk of cancer.

Comparative Effect of Statins and Omega-3 Supplementation on Cardiovascular Events: Meta-Analysis and Network Meta-Analysis of 63 Randomized Controlled Trials Including 264,516 Participants.

Statins and omega-3 supplementation have been recommended for cardiovascular disease prevention, but comparative effects have not been investigated. This study aimed to summarize current evidence of the effect of statins and omega-3 supplementation on cardiovascular events. A meta-analysis and a network meta-analysis of 63 randomized controlled trials were used to calculate pooled relative risks (RRs) and 95% confidence intervals (CIs) for the effects of specific statins and omega-3 supplementation compared with controls. Overall, the statin group showed significant risk reductions in total cardiovascular disease, coronary heart disease, myocardial infarction, and stroke; however, omega-3 supplementation significantly decreased the risks of coronary heart disease and myocardial infarction only, in the comparison with the control group. In comparison with omega-3 supplementation, pravastatin significantly reduced the risks of total cardiovascular disease (RR = 0.81, 95% CI = 0.72-0.91), coronary heart disease (RR = 0.75, 95% CI = 0.60-0.94), and myocardial infarction (RR = 0.71, 95% CI = 0.55-0.94). Risks of total cardiovascular disease, coronary heart disease, myocardial infarction, and stroke in the atorvastatin group were statistically lower than those in the omega-3 group, with RRs (95% CIs) of 0.80 (0.73-0.88), 0.64 (0.50-0.82), 0.75 (0.60-0.93), and 0.81 (0.66-0.99), respectively. The findings of this study suggest that pravastatin and atorvastatin may be more beneficial than omega-3 supplementation in reducing the risk of total cardiovascular disease, coronary heart disease, and myocardial infarction.

Intake or Blood Levels of n-3 Polyunsaturated Fatty Acids and Risk of Colorectal Cancer: A Systematic Review and Meta-analysis of Prospective Studies.

BACKGROUND: Previous results of the association between n-3 polyunsaturated fatty acids (PUFA) and colorectal cancer were inconsistent. We conducted a systematic review and meta-analysis of prospective studies. METHODS: The PubMed and Embase databases were searched through July 10, 2019, followed by a manual search. A random-effects model was used. RESULTS: Twenty prospective studies, including 18,102 cases and 1,360,046 participants, were included. The pooled RR of colorectal cancer for the highest versus lowest category of n-3 PUFA intake was 0.97 [95% confidence interval (CI), 0.90-1.04]. Regarding the type of n-3 PUFA, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) intakes were inversely associated with 11% (RR = 0.89; 95% CI, 0.80-0.99) and 12% (RR = 0.88; 95% CI, 0.81-0.96) lower colorectal cancer risks, respectively, in the comparison of the highest versus lowest category. Increments of 0.1 g/day of EPA (RR = 0.95; 95% CI, 0.92-0.98) and DHA (RR = 0.97; 95% CI, 0.95-0.99) intakes were associated with a lower colorectal cancer risk. Regarding the blood levels of n-3 PUFAs, the pooled RR of colorectal cancer for the highest versus lowest category of blood levels of n-3 PUFAs was 0.79 (95% CI, 0.64-0.98). The risk of colorectal cancer decreased by 4% for every 1% increase in blood n-3 PUFA levels (RR = 0.96; 95% CI, 0.92-1.00). CONCLUSIONS: High blood n-3 PUFA levels are inversely associated with colorectal cancer risk, and high n-3 PUFA intake is suggestively associated with lower colorectal cancer risk. IMPACT: Our findings suggest that high blood n-3 PUFA levels may be associated with reduced colorectal cancer risk, but further studies are needed.

Protective Effect of Green Tea Consumption on Colorectal Cancer Varies by Lifestyle Factors.

The inconsistent findings regarding green tea intake and colorectal cancer (CRC) risk in several epidemiological studies might result from variations in lifestyle factors. Therefore, we examined whether increased green tea intake was associated with a decreased risk of CRC and how the risk of CRC was altered by the protective effect of green tea consumption and five health-related factors. A case-control study including 2742 participants (922 cases and 1820 controls) was conducted in Korea. Green tea consumption was assessed using a semiquantitative food frequency questionnaire. The risk of CRC was approximately 40% less in the participants in the highest green tea intake tertile than in participants in the lowest green tea intake tertile. Of the five lifestyle factors examined, high body mass index and physical inactivity were independent risk factors for CRC. Regarding the interactions between tea consumption and lifestyle factors, high green tea consumption was associated with a decreased risk of CRC, with or without considering lifestyle factors. However, moderate green tea consumption increased the risk of CRC among ever-smokers, ever-drinkers and the high-inflammatory diet group. Increased consumption of green tea might be helpful to reduce the risk of CRC in those with an unhealthy lifestyle.

Dietary n-3 and n-6 polyunsaturated fatty acids, the FADS gene, and the risk of gastric cancer in a Korean population.

n-3 polyunsaturated fatty acids (PUFAs) and n-6 PUFAs are reported to have immunomodulatory effects, but few studies have examined these functions. Thus, we examined whether dietary n-3 and n-6 PUFAs are associated with the risk of gastric cancer and further investigated whether fatty acid desaturases 1 and 2 (FADS1 and FADS2) modify this association. In a case-control study, 1,464 participants (402 cases and 1,062 controls) were enrolled. A semi-quantitative food frequency questionnaire was utilized to measure dietary PUFA intake. Genotyping was performed using the Axiom® Exome 319 Array. Multivariable logistic models were established after adjusting for confounding variables. The risk of gastric cancer was significantly decreased among participants who had the highest tertile intake of docosahexaenoic acid (DHA), an n-3 PUFA, even after adjusting for covariates [odds ratios (OR) = 0.72, 95% confidence intervals (95% CIs) = 0.53-0.99]. However, no significant interaction according to FADS1 rs174546 or FADS2 rs174583 was observed. In conclusion, we observed a significant inverse association between dietary DHA and the risk of gastric cancer but found that FADS1 rs174546 and FADS2 rs174583 did not modify the association between dietary n-3 or n-6 PUFAs and gastric cancer risk.

Coffee Consumption and the Risk of Obesity in Korean Women.

Instant coffee mixes that contain sugar and non-dairy creamer account for 80-90% of the total coffee market in Korea. The objective of this study was to investigate the relationship between coffee consumption and obesity in Korean women. We included 5995 women who participated in a health screening examination at the Korean National Cancer Center between 2007 and 2016. Daily coffee consumption and the use of sugar and creamer in coffee was evaluated using a 106-item food frequency questionnaire. Obesity was assessed by body mass index (BMI), and abdominal obesity was assessed by waist circumference (WC). A multiple logistic regression model was used to calculate the odds ratio (OR) of obesity according to coffee consumption. After multivariate adjustment, high coffee consumption was positively associated with obesity as measured by BMI (≥3 cups vs. no drinks, OR = 2.52; 95% confidence interval (CI) = 1.91-3.34; p for the trend < 0.001) and abdominal obesity as measured by WC (≥3 cups vs. no drinks, OR = 2.11; 95% CI = 1.59-2.79; p for the trend < 0.001). The positive association between daily coffee consumption and obesity prevalence was not altered by menopause. The amount of coffee with additives consumed per day by Korean women was positively correlated with the prevalence of obesity, but causation cannot be determined due to the cross-sectional nature of the study design. The mechanism underlying the observed relationship is yet to be elucidated.

Efficacy of Ginseng Supplements on Fatigue and Physical Performance: a Meta-analysis.

We conducted a meta-analysis to investigate the efficacy of ginseng supplements on fatigue reduction and physical performance enhancement as reported by randomized controlled trials (RCTs). RCTs that investigated the efficacy of ginseng supplements on fatigue reduction and physical performance enhancement compared with placebos were included. The main outcome measures were fatigue reduction and physical performance enhancement. Out of 155 articles meeting initial criteria, 12 RCTs involving 630 participants (311 participants in the intervention group and 319 participants in the placebo group) were included in the final analysis. In the fixed-effect meta-analysis of four RCTs, there was a statistically significant efficacy of ginseng supplements on fatigue reduction (standardized mean difference, SMD = 0.34; 95% confidence interval [CI] = 0.16 to 0.52). However, ginseng supplements were not associated with physical performance enhancement in the fixed-effect meta-analysis of eight RCTs (SMD = -0.01; 95% CI = -0.29 to 0.27). We found that there was insufficient clinical evidence to support the use of ginseng supplements on reducing fatigue and enhancing physical performance because only few RCTs with a small sample size have been published so far. Further lager RCTs are required to confirm the efficacy of ginseng supplements on fatigue reduction.

Effect of dietary vitamin C on gastric cancer risk in the Korean population.

AIM: To investigate the effects of dietary vitamin C and foods containing vitamin C on gastric cancer risk. METHODS: Our study included 830 control subjects and 415 patients. Data regarding demographics, medical history, and lifestyle, including dietary and nutrient intake, were collected using reliable self-administered questionnaires. Dietary intake information was collected from the participants using a food frequency questionnaire that has been previously reported as reliable and valid. A rapid urease test and a histological evaluation were used to determine the presence of Helicobacter pylori (H. pylori) infection. Twenty-three vitamin C-contributing foods were selected, representing over 80% of the cumulative vitamin C contribution. RESULTS: In analyses adjusted for first-degree family history of gastric cancer, education level, job, household income, smoking status, and regular exercise, an inverse association between vitamin C intake and gastric cancer risk was observed for the highest (≥ 120.67 mg/d) vs the lowest (< 80.14 mg/d) intake category [OR (95%CI): 0.64 (0.46-0.88)], with a significant trend across the three intake categories (P = 0.007). No protective effect of vitamin C was detected after stratification by gender. No effect of vitamin C intake on the gastric cancer incidence was found in either men or women infected with H. pylori. Vitamin C-contributing foods, including cabbage [0.45 (0.32-0.63), 0.50 (0.34-0.75), 0.45 (0.25-0.81)], strawberries [0.56 (0.40-0.78), 0.49 (0.32-0.74), 0.52 (0.29-0.93)], and bananas [0.40 (0.29-0.57), 0.41 (0.27-0.62), 0.34 (0.19-0.63)], were protective factors against the risk of gastric cancer based on the results of the overall adjusted analyses and the results for men and women, respectively. CONCLUSION: A protective effect of vitamin C and vitamin C-contributing foods against gastric cancer was observed. Further studies using larger sample sizes are required to replicate our results.

Oral Contraceptive Use, Micronutrient Deficiency, and Obesity among Premenopausal Females in Korea: The Necessity of Dietary Supplements and Food Intake Improvement.

This study addressed the associations between oral contraceptive (OC) use and obesity as measured by recording the body mass index (BMI) of premenopausal females, and possible interactions with micronutrient intake were considered. A group of 39,189 premenopausal females aged 35-59 were included in the analysis; they were in the Health Examinee cohort. Participant BMIs were calculated from anthropometric measurements, and females with a BMI≥25kg/m2 were considered obese. Individual OC use, age at first OC use, duration of OC use, nutrient intake, and other covariates were measured with a structured questionnaire. A multivariate logistic regression with an interaction term was applied to identify the odds ratio (OR) and 95% confidence intervals (CI) between OC use and obesity along with consideration of micronutrient intake interactions. OC use is associated with an increased risk of obesity (OR = 1.12, 95% CI = 1.04-1.20), and females who used OCs for more than 6 months over their lifetimes were more likely to be obese (OR = 1.15, 95% CI = 1.01-1.32) compared with those who used OCs for <6 months. There were interaction effects between phosphorus, potassium, vitamin A, vitamin B1, vitamin B2, niacin, vitamin C intake and total duration of OC use on being obesity (P-value<0.05). When stratified by micronutrient intake, the associations between total OC use duration and obesity were present only among those with calcium, phosphorus, potassium, vitamin A, B1, B2, C, niacin, and folate intakes below the recommended levels. Efforts to estimate nutrient intake and prevent micronutrient depletion with supplements or food should be considered by clinicians for females who take OC for a long period.

Isoflavones from phytoestrogens and gastric cancer risk: a nested case-control study within the Korean Multicenter Cancer Cohort.

BACKGROUND: The role of soybean products in gastric cancer risk is not clear in epidemiologic studies due to measurement error from dietary intake questionnaires and due to different degrees of bias according to study design. To examine the association between soybean products and gastric cancer risk, we measured phytoestrogen biological markers in a nested case-control study. METHODS: The study population was composed of 131 cases and 393 matched controls within the Korean Multicenter Cancer Cohort. The concentrations of the four biomarkers in the plasma samples were measured using time-resolved fluoroimmunoassay. Conditional and unconditional logistic regression models were used to compute the odds ratio (OR) and 95% confidence intervals (CI). RESULTS: Median plasma concentrations of genistein (229 nmol/L for controls, 181.8 nmol/L for cases; P=0.07) and daidzein (131.2 nmol/L for controls, 80.5 nmol/L for cases; P=0.04) in cases were lower than in controls, whereas equol concentrations were similar. Compared with the reference group, gastric cancer risk decreased in the highest groups for genistein (OR, 0.54; 95% CI, 0.31-0.93) and daidzein (OR, 0.21; 95% CI, 0.08-0.58). Higher equol concentrations were associated with a decreased risk for gastric cancer (OR, 0.50; 95% CI, 0.27-0.90). The combination of the highest concentrations for each isoflavone category was associated with a 0.09-fold decreased risk for gastric cancer compared with the combination of the lowest concentrations for each category. There was no association between plasma lignan concentrations and gastric cancer. CONCLUSIONS: High serum concentrations of isoflavones were associated with a decreased risk for gastric cancer. IMPACT: These results suggest a beneficial effect of high soybean product intake for gastric cancer risk.

Sociodemographic and lifestyle factors are associated with the use of dietary supplements in a Korean population.

OBJECTIVE: The use of dietary supplements has been increasing rapidly in Korea over the last decade. The aim of this study was to investigate associations between the pattern of dietary supplement use and the sociodemographic/lifestyle characteristics of Korean consumers. METHODS: Participants were asked to complete a self-administered questionnaire on their sociodemographic and lifestyle characteristics, perceived health status, and regular dietary supplement use. RESULTS: A total of 697 men and 832 women completed the questionnaire. Of the respondents, 44.3% of the men and 53.2% of the women used some kind of dietary supplement regularly. Dietary supplement users were more likely to be women (P < 0.001), to be older than 50 years (P < 0.001), to have a higher household income (P = 0.003), to engage in moderate or vigorous physical activity (P < 0.032), to perceive themselves as healthy (P = 0.026), and to have received a diagnosis of a chronic disease (P < 0.001). In addition, the type of dietary supplements used varied with respect to sociodemographic and lifestyle factors. Among dietary supplement users, men preferred ginseng, and older respondents were more likely to use carbohydrate supplements and less likely to use lipid supplements. Those who had a lower BMI, were ex-smokers, or were nondrinkers preferred either vitamins or minerals. Those who were highly physical active or were nondrinkers tended to prefer either vitamin/mineral complexes or carbohydrate supplements. CONCLUSIONS: The use of dietary supplements was related to sociodemographic and lifestyle factors in a Korean population.

Intakes of vitamin A, C, and E, and beta-carotene are associated with risk of cervical cancer: a case-control study in Korea.

Cervical cancer is one of the most common gynecological malignancies in Korea, although the incidence has been declining in recent years. This study explored whether antioxidant vitamin intakes influenced the risk of cervical cancer. The association between antioxidant vitamin intakes and cervical cancer risk was calculated for 144 cervical cancer cases and 288 age-matched, hospital-based controls using unconditional logistic regression models. Cases reported statistically lower mean dietary intakes of vitamin A, beta -carotene, and vitamin C than did controls. Total intakes of vitamins A and E, which included both dietary and supplement intake, were also lower in cases. Those patients in the highest quartiles of dietary vitamin A, beta -carotene, and vitamin C intakes had statistically significantly lower cervical cancer risks than those in the lowest quartiles for vitamin A, beta -carotene, and vitamin C: odds ratio (OR) = 0.36 [95% confidence interval (CI) = 0.19-0.69), OR = 0.48 (CI = 0.26-0.88), and OR = 0.36 (CI = 0.18-0.69), respectively. Total intakes of vitamins A, C, and E were strongly inversely associated with cervical cancer risk: OR = 0.35 (CI = 0.19-0.65), OR = 0.35 (CI = 0.19-0.66), and OR = 0.53 (CI = 0.28-0.99), respectively. The findings support a role for increased antioxidant vitamin intake in decreasing the risk of cervical cancer. These associations need to be assessed in large prospective studies with long-term follow-up.

Factors affecting the use of dietary supplements by Korean adults: data from the Korean National Health and Nutrition Examination Survey III.

We investigated the use of dietary supplements among adult Korean consumers, including associations involving sociodemographic variables, lifestyle characteristics, health-related factors, and dietary supplement use. The data were derived from the 2005 third Korean National Health and Nutrition Examination data among 4,775 adults (1,983 men and 2,792 women) regarding medical examinations and diet. In general, 21.8% of the male and 32.0% of the female respondents used dietary supplements regularly. Dietary supplement users tended to reside in large cities and to have higher monthly incomes. People with bone diseases consumed 1.71 times higher (95% confidence interval [CI] 1.19 to 2.46) amounts of supplements than those without such diseases. Among dietary supplement users, female respondents expressed a preference for carbohydrates (adjusted odds ratio [OR] 3.79; 95% CI 1.33 to 10.79). The intake rates for vitamin/mineral complexes tended to increase with age (P for trend 0.007) and respondents earning higher incomes expressed a preference for minerals, vitamin/mineral complexes, and terpenes. Carbohydrate use decreased among those with higher education levels: high school graduates were 0.48 times (95% CI 0.23 to 0.99) and those with college or above were 0.24 times (95% CI 0.07 to 0.83) more likely to use carbohydrates. Nonsmokers (OR 2.63; 95% CI 1.68 to 4.13), nondrinkers (OR 1.73; 95% CI 1.09 to 2.73), and those with bone disease (OR 2.19; 95% CI 1.24 to 3.86) expressed a preference for vitamins. Those who had been diagnosed with a chronic disease showed a preference for terpenes (OR 2.81; 95% CI 1.03 to 7.68). These results indicate that dietary supplement use might be affected by certain sociodemographic, lifestyle, and health characteristics.