Identification of major dietary patterns in Korean adults and their association with cancer risk in the Cancer Screening Examination Cohort

Difference in Gastrointestinal Cancer Risk and Mortality by Dietary Pattern Analysis: A Systematic Review and Meta-Analysis

CONTEXT

Several studies have demonstrated that dietary patterns identified by a posteriori and hybrid methods are associated with gastrointestinal (GI) cancer risk and mortality. These studies applied different methods for analyzing dietary data and reported inconsistent findings.

OBJECTIVE

This systematic review and meta-analysis were aimed to determine the association between dietary patterns, derived using principal component analysis (PCA) and reduced rank regression (RRR), and GI cancer risk and GI cancer-caused mortality.

DATA SOURCE

Articles published up to June 2023 in English were eligible for inclusion. The Medline, SCOPUS, Cochrane Library, CINHAL, PsycINFO, ProQuest, and Web of Sciences databases were used to identify prospective studies. The Preferred Reporting Item for Systematic Review and Meta-analysis Protocol 2020 was used to report results.

DATA EXTRACTION

A total of 28 studies were eligible for inclusion. Varied approaches to deriving dietary patterns were used, including PCA (n = 22), RRR (n = 2), combined PCA and RRR (n = 1), cluster analysis (CA; n = 2) and combined PCA and CA (n = 1).

DATA ANALYSIS

Two dietary patterns, "healthy" and "unhealthy," were derived using PCA and RRR. The healthy dietary pattern was characterized by a higher intake of fruits, whole grains, legumes, vegetables, milk, and other dairy products, whereas the unhealthy dietary pattern was characterized by a higher intake of red and processed meat, alcohol, and both refined and sugar-sweetened beverages. The findings indicated that the PCA-derived healthy dietary pattern was associated with an 8% reduced risk (relative risk [RR], 0.92; 95% CI, 0.87-0.98), and the unhealthy dietary pattern was associated with a 14% increased risk (RR, 1.14; 95% CI, 1.07-1.22) of GI cancers. Similarly, the RRR-derived healthy dietary pattern (RR, 0.83; 95% CI, 0.61-1.12) may be associated with reduced risk of GI cancers. In contrast, the RRR-derived unhealthy dietary pattern (RR, 0.93; 95% CI, 0.57-1.52) had no association with a reduced risk of GI cancers. Similarly, evidence suggested that PCA-derived healthy dietary patterns may reduce the risk of death from GI cancers, whereas PCA-derived unhealthy dietary patterns may increase the risk.

CONCLUSION

Findings from prospective studies on the association of PCA-derived dietary patterns and the risk of GI cancers support the evidence of healthy and unhealthy dietary patterns as either protective or risk-increasing factors for GI cancers and for survivorship, respectively. The findings also suggest that the RRR-derived healthy dietary pattern reduces the risk of GI cancers (albeit with low precision), but no association was found for the RRR-derived unhealthy dietary pattern. Prospective studies are required to further clarify disparities in the association between PCA- and RRR-derived dietary patterns and the risk of GI cancers. Systematic review registration: PROSPERO registration no. CRD42022321644.

Association between dietary intake networks identified through a Gaussian graphical model and the risk of cancer: a prospective cohort study

PURPOSE

In this study, we aimed to investigate the association between dietary communities identified by a Gaussian graphical model (GGM) and cancer risk.

METHODS

We performed GGM to identify the dietary communities in a Korean population. GGM-derived communities were then scored and investigated for their association with cancer incidence in the entire population as well as in the 1:1 age- and sex-matched subgroup using a Cox proportional hazards model. In the sensitivity analysis, GGM-derived communities were compared to dietary patterns (DPs) that were identified by principal component analysis (PCA) and reduced rank regression (RRR).

RESULTS

During a median time to follow-up of 6.6 years, 397 cancer cases were newly diagnosed. The GGM identified 17 and 16 dietary communities for the total and matched populations, respectively. For each one-unit increase in the standard deviation of the community-specific score of the community that was composed of dairy products and bread, there was a reduced risk of cancer according to the fully adjusted model (HR: 0.80, 95% CI: 0.66-0.96). In the matched population, the third tertile of the community-specific score of the community composed of poultry, seafood, bread, cakes and sweets, and meat by-products showed a significantly reduced risk of cancer compared to that of the lowest tertile in the fully adjusted model (HR: 0.66, 95% CI: 0.50-0.86, p-trend = 0.002).

CONCLUSION

We found that the GGM-identified community composed of dairy products and bread showed a reduced risk of cancer. Further population-based prospective studies should be conducted to examine possible associations of dietary intake and specific cancer types.

Nutrition-wide association study of microbiome diversity and composition in colorectal cancer patients

BACKGROUND

The effects of diet on the interaction between microbes and host health have been widely studied. However, its effects on the gut microbiota of patients with colorectal cancer (CRC) have not been elucidated. This study aimed to investigate the association between diet and the overall diversity and different taxa levels of the gut microbiota in CRC patients via the nutrition-wide association approach.

METHODS

This hospital-based study utilized data of 115 CRC patients who underwent CRC surgery in Department of Surgery, Seoul National University Hospital. Spearman correlation analyses were conducted for 216 dietary features and three alpha-diversity indices, Firmicutes/Bacteroidetes ratio, and relative abundance of 439 gut microbial taxonomy. To identify main enterotypes of the gut microbiota, we performed the principal coordinate analysis based on the β-diversity index. Finally, we performed linear regression to examine the association between dietary intake and main microbiome features, and linear discriminant analysis effect size (LEfSe) to identify bacterial taxa phylogenetically enriched in the low and high diet consumption groups.

RESULTS

Several bacteria were enriched in patients with higher consumption of mature pumpkin/pumpkin juice (ρ, 0.31 to 0.41) but lower intake of eggs (ρ, -0.32 to -0.26). We observed negative correlations between Bacteroides fragilis abundance and intake of pork (belly), beef soup with vegetables, animal fat, and fatty acids (ρ, -0.34 to -0.27); an inverse correlation was also observed between Clostridium symbiosum abundance and intake of some fatty acids, amines, and amino acids (ρ, -0.30 to -0.24). Furthermore, high intake of seaweed was associated with a 6% (95% CI, 2% to 11%) and 7% (95% CI, 2% to 11%) lower abundance of Rikenellaceae and Alistipes, respectively, whereas overall beverage consumption was associated with an 10% (95% CI, 2% to 18%) higher abundance of Bacteroidetes, Bacteroidia, and Bacteroidales, compared to that in the low intake group. LEfSe analysis identified phylogenetically enriched taxa associated with the intake of sugars and sweets, legumes, mushrooms, eggs, oils and fats, plant fat, carbohydrates, and monounsaturated fatty acids.

CONCLUSIONS

Our data elucidates the diet-microbe interactions in CRC patients. Additional research is needed to understand the significance of these results in CRC prognosis.

Health, lifestyle and sociodemographic characteristics are associated with Brazilian dietary patterns: Brazilian National Health Survey

This study aimed to identify Brazilian dietary patterns and their associations with health, lifestyle and sociodemographic characteristics. Data from the Brazilian National Health Survey conducted in 2013 were used. A questionnaire was applied containing 22 items related to dietary consumption. Dietary patterns were determined through factor analysis (FA). Poisson regression models, with robust variance, were used to identify associations between dietary patterns and independents variables. Statistical significance was defined as p-value<0.05. Data were analysed for 60,202 adults (estimated population size: 146,308,458). FA identified three dietary patterns: healthy, protein, and western. The younger age group (18-24 years) had a lower adherence to the healthy pattern (PR:0.53; 95%CI:0.49-0.58) and greater adherence to the protein (PR:1.52; 95%CI:1.42-1.62) and western (PR:1.80; 95%CI:1.68-1.93) patterns compared to the elderly (≥60 years). Women had a greater association with the healthy pattern (PR:1.32; 95%CI:1.28-1.38) and lower association with the protein pattern (PR:0.80; 95%CI:0.77-0.82) compared to men. Illiterate participants showed lower adherence to the healthy (PR:0.58; 95%CI:0.53-0.63) and western (PR:0.54; 95%CI:0.48-0.62) patterns compared to those with higher educational levels. Smokers had lower adherence to the healthy (PR:0.76; 95%CI:0.71-0.81) and higher adherence to the protein (PR:1.14; 95%CI:1.11-1.19) patterns compared to non-smokers. Participants with poor/very poor self-rated health status had a lower adherence to the healthy (PR:0.79; 95%CI:0.73-0.86) and western (PR:0.81; 95%CI:0.73-0.89) patterns compared to those in a very good/good self-rated health status. Multimorbidity was positively associated with the healthy pattern (PR:1.18; 95%CI:1.11-1.26) and inversely associated with the protein pattern (PR:0.88; 95%CI:0.80-0.96) compared to participants without comorbidities. We suggest that strategies to promote healthy eating should consider health, lifestyle and sociodemographic characteristics in the Brazilian population.

Differences in Dietary Patterns Identified by the Gaussian Graphical Model in Korean Adults With and Without a Self-Reported Cancer Diagnosis

BACKGROUND

The synergistic effect of food groups on health outcomes is better captured by examining dietary patterns (DPs) than single food groups. Regarding this issue, a Gaussian graphical model (GGM) can identify pairwise correlations between food groups and adjust for the remaining items. However, the application of GGMs in the nutritional field has not been widely investigated, especially in Korean adults.

OBJECTIVE

The aim of this study was to identify the major DPs of Korean adults by using a GGM and to examine the associations between the DP scores and prevalence of self-reported cancer.

DESIGN

This cross-sectional study used baseline data from the 2007-2019 Cancer Screenee Cohort of the National Cancer Center, Korea.

PARTICIPANTS/SETTING

In total, 10,777 Korean adults who completed a questionnaire regarding their general medical history, including clinical test results, and a validated food frequency questionnaire were included.

MAIN OUTCOME MEASURES

The main outcome measure was the prevalence of self-reported cancer at baseline.

STATISTICAL ANALYSIS

DP networks were identified using a GGM. The GGM-identified networks were scored and categorized into tertiles, and their association with the prevalence of self-reported cancer was investigated using a multivariable logistic regression model.

RESULTS

The GGM identified the following 4 DP networks: principal, oil-sweet, meat, and fruit. After adjusting for covariates, the odds of moderate and high consumption of foods in the oil-sweet DP for participants who self-reported cancer were 25% and 34% lower than those for participants who did not report a cancer diagnosis (odds ratio [OR] = 0.75, 95% confidence interval [CI] = 0.62-0.90 and OR = 0.66, 95% CI = 0.53-0.81, respectively). Additionally, the odds of meat DP consumption in the self-reported cancer group was 29% lower than in participants who did not report a cancer diagnosis (OR = 0.71 and 95% CI = 0.57-0.88). In contrast, an increase in the odds of fruit DP consumption was observed for self-reported cancer participants (OR = 1.34 and 95% CI = 1.09-1.65). Similar results were observed among the female but not the male subjects.

CONCLUSIONS

GGM is a novel method that can distinguish the direct pairwise correlation of food groups and control for the indirect effect of other foods. Future large-scale longitudinal population-based studies are needed to build on these findings in general populations.

Dietary patterns and gastric cancer risk in a Korean population: a case-control study

PURPOSE

Dietary pattern analysis has been considered as an approach to capture the complex interactions of overall diet, which are often lost in studies of single dietary components (e.g., foods and nutrients). The aim of this study was to identify the major dietary patterns of Koreans via principal component analysis based on the food groups and to investigate the association between dietary patterns and gastric cancer (GC) risk.

METHODS

In this study, participants were recruited from the National Cancer Center, Korea. Among them, 415 cases were diagnosed with early GC, and 830 controls were age- and sex-matched at a ratio of 1:2. To determine the subjects' dietary patterns, 34 predefined food groups based on the 106-item semiquantitative food frequency questionnaire (SQFFQ) were used. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated across the tertiles of dietary pattern scores using logistic regression models.

RESULTS

The two dietary patterns derived in this study were named westernized and prudent. Those patterns explained 24.83% of the total variation in food intake. Higher scores on the prudent pattern was inversely associated with the risk of GC (OR [95% CI] for the highest vs. lowest tertiles: 0.58 [0.41-0.84], p for trend = 0.004).

CONCLUSION

Our findings suggest that adherence to the prudent dietary pattern represented by high loadings of vegetables and fruits, was associated with lower GC risk. Further studies with a prospective design and larger sample sizes are necessary.

Identification of Dietary Pattern Networks Associated with Gastric Cancer Using Gaussian Graphical Models: A Case-Control Study

Gaussian graphical models (GGMs) are novel approaches to deriving dietary patterns that assess how foods are consumed in relation to one another. We aimed to apply GGMs to identify dietary patterns and to investigate the associations between dietary patterns and gastric cancer (GC) risk in a Korean population. In this case-control study of 415 GC cases and 830 controls, food intake was assessed using a 106-item semiquantitative food frequency questionnaire that captured 33 food groups. The dietary pattern networks corresponding to the total population contained a main network and four subnetworks. For the vegetable and seafood network, those who were in the highest tertile of the network-specific score showed a significantly reduced risk of GC both in the total population (OR = 0.66, 95% CI = 0.47-0.93, p for trend = 0.018) and in males (OR = 0.55, 95% CI = 0.34-0.89, p for trend = 0.012). Most importantly, the fruit pattern network was inversely associated with the risk of GC for the highest tertile (OR = 0.56, 95% CI = 0.38-0.81, p for trend = 0.002). The identified vegetable and seafood network and the fruit network showed a protective effect against GC development in Koreans.

Dietary pattern, dietary total antioxidant capacity, and dyslipidemia in Korean adults

Background

Abnormal diet is considered to be an important risk factor for dyslipidemia. However, so far, most studies have focused on the association between single factors only, such as specific nutrients, foods, or dietary patterns, and dyslipidemia risk. This study aimed to examine the association of the joint interaction between dietary pattern and dietary total antioxidant capacity (TAC) with dyslipidemia.

Methods

We performed a dietary pattern analysis and calculated the dietary TAC based on 24-h dietary recall (DR) data from Korea National Health and Nutrition Examination Survey (KNHANES) 2007–2012, which is representative population-based cross-sectional survey in Korea. A total of 29,624 participants aged over 19 years were included for the analysis. The number of people with hypercholesterolemia, hypertriglyceridemia, and hypoHDL-cholesterolemia was 3703, 3513, and 9802, respectively. We examined the association between the joint classifications of dietary pattern score tertiles and dietary TAC level tertiles and dyslipidemia.

Results

Our results demonstrated that the “Rice & Kimchi” pattern was associated with low prevalence of hypercholesterolemia, and high prevalence of hypertriglyceridemia and hypoHDL-cholesterolemia; whereas the pattern of both “Oil, sweets, fish & other vegetables” and “Grain, bean, nuts, vegetables & fruits” were associated with low prevalence of hypertriglyceridemia. Also we demonstrated that for all dietary patterns except for the “Grain, bean, nuts, vegetables & fruits”, dietary TAC was inversely associated with hypertriglyceridemia.

Conclusion

This study provides basic data for the lipid-lowering effect of dietary TAC and its interaction with dietary patterns. Further study will be needed to investigate the association between dietary TAC and dietary patterns with other diseases like metabolic syndrome, cardiovascular disease, or cancer.

Electronic supplementary material

The online version of this article (10.1186/s12937-019-0459-x) contains supplementary material, which is available to authorized users.

Contribution of the polymorphism rs1800469 of transforming growth factor β in the development of myocardial infarction: meta-analysis of 5460 cases and 8413 controls (MOOSE-compliant article)

Studies investigating the association between transforming growth factor (TGF-β-509C/T, rs1800469) promoter polymorphism and myocardial infarction (MI) risk reported inconsistent results. The aim of our study was to assess the association between the 509C/T polymorphism of the TGF-β gene (rs1800469) and MI risk.A total of 5460 cases and 8413 controls in 7 case-control studies were incorporated in our current meta-analysis. The original studies were selected through searching the databases of the PubMed and EMBASE. The odds ratio (OR) and 95% confidence interval (95% CI) of TGF-β 509C/T (rs1800469) for MI risk were applied to estimate the strength of the association.Our results showed that T allele carriers had a 13% increased risk of MI, when compared with the C allele carriers (OR = 1.13, 95% CI: 1.00-1.27). In the subset analysis by the type of MI, significantly elevated risk of MI was associated with the homozygote TT and heterozygote C/T in no-AMI subjects, when compared with the CC homozygote carriers (OR = 1.12, 95% CI:1.02-1.23).Our meta-analysis shows that the polymorphism with homozygote TT and heterozygote C/T of TGF-β 509C/T (rs1800469) is significantly associated with the increased risk of MI.

Microbial Ecology of Fermented Vegetables and Non-Alcoholic Drinks and Current Knowledge on Their Impact on Human Health

Fermented foods are currently experiencing a re-discovery, largely driven by numerous health benefits claims. While fermented dairy, beer, and wine (and other alcoholic fermented beverages) have been the subject of intensive research, other plant-based fermented foods that are in some case widely consumed (kimchi/sauerkraut, pickles, kombucha) have received less scientific attention. In this chapter, the current knowledge on the microbiology and potential health benefits of such plant-based fermented foods are presented. Kimchi is the most studied, characterized by primarily acidic fermentation by lactic acid bacteria. Anti-obesity and anti-hypertension properties have been reported for kimchi and other pickled vegetables. Kombucha is the most popular non-alcoholic fermented drink. Kombucha's microbiology is remarkable as it involves all fermenters described in known fermented foods: lactic acid bacteria, acetic acid bacteria, fungi, and yeasts. While kombucha is often hyped as a "super-food," only antioxidant and antimicrobial properties toward foodborne pathogens are well established; and it is unknown if these properties incur beneficial impact, even in vitro or in animal models. The mode of action that has been studied and demonstrated the most is the probiotic one. However, it can be expected that fermentation metabolites may be prebiotic, or influence host health directly. To conclude, plant-based fermented foods and drinks are usually safe products; few negative reports can be found, but more research, especially human dietary intervention studies, are warranted to substantiate any health claim.