The Association between Dietary Inflammatory Index (DII) and Cancer Risk in Korea: A Prospective Cohort Study within the KoGES-HEXA Study

The association of the dietary inflammatory potential with risk of overall and site-specific cancers: A community-based longitudinal study in the UK Biobank

OBJECTIVES

The association of the dietary inflammatory potential with cancer risk remains uncertain. We examined the relationship of the dietary inflammatory potential with risk of overall and site-specific cancers and explored its sex and age differences.

DESIGN

A community-based longitudinal study.

SETTING

Participants from the UK Biobank completed baseline surveys during 2006-2010 and were followed for up to 15 years to detect incident cancer.

PARTICIPANTS

170,899 cancer-free participants with dietary data available (mean age: 55.73 ± 7.95, 54.10% female).

MEASUREMENTS

At baseline, dietary intake was assessed with a 24-h dietary record for up to 5 times. The inflammatory diet index (IDI) was calculated to assess the dietary inflammatory potential as a weighted sum of 31 food groups (including 14 anti-inflammatory and 17 pro-inflammatory) based on plasma high-sensitivity C-reactive protein (hsCRP) levels, and tertiled as low (indicating low-inflammatory diet), moderate, and high IDI (as reference). Overall and site-specific cancers were ascertained via linkage to routine hospital admission, cancer registry, and death certificate data. Data were analyzed using Cox regression and Laplace regression.

RESULTS

During the follow-up (median 10.32 years, interquartile range: 9.95-11.14 years), 18,884 (11.05%) participants developed cancer. In multi-adjusted Cox regression, low IDI scores were associated with decreased risk of rectal cancer (hazard ratio [95% confidence interval, CI] 0.76 [0.61, 0.94]), thyroid cancer [0.45 (0.27, 0.74)], lung cancer [0.73 (0.61, 0.88)]. However, the association between IDI score and the risk of overall cancer was not significant. Laplace regression analysis showed that 10th percentile differences (95% CIs) of cancer onset time for participants with low IDI scores was prolonged by 1.29 (0.32, 2.27), 1.44 (0.58, 2.30), and 2.62 (0.98, 4.27) years for rectal cancer, thyroid cancer, and lung cancer, respectively, compared to those with high IDI scores. Stratified analysis revealed that low IDI scores were associated with a lower risk of rectal cancer (p interaction between IDI score and sex = 0.035) and lung cancer in males, but not in females, and with a reduced risk of thyroid cancer in females, but not in males. Moreover, low IDI scores were associated with a reduced risk of rectal cancer and lung cancer in the participants aged ≥60 years, but not in those <60 years, and with a reduced risk of thyroid cancer in those aged ≥60 years and <60 years.

CONCLUSIONS

A low-inflammatory diet is associated with decreased risk and prolonged onset time of rectal cancer and lung cancer, especially among males and individuals aged ≥60 years, and thyroid cancer among females.

The Association between Dietary Inflammatory Potential and Urologic Cancers: A Meta-analysis

A meta-analysis published in 2018 indicated a significant association between the dietary inflammatory index (DII) and risk of urologic cancers (UC). The number of included studies was limited, and more research has been published on this topic since then. The current study aimed to find a more precise estimate of the association between dietary inflammatory potential and risk of UC by updating the previous meta-analysis. The PubMed and Embase databases were searched between January 2015 and April 2023 to identify eligible articles. Combined relative risk (RR) and 95% confidence intervals (CI) were calculated by random-effects model to assess the association between dietary inflammatory potential and risk of UC by comparison of the highest versus the lowest category of the DII/empirical dietary inflammatory pattern (EDIP) or by using the continuous DII/EDIP score. The analysis, including 23 studies with 557,576 subjects, showed different results for UC. There was a significant association for prostate cancer among case-control studies (RR = 1.75, 95% CI: 1.34-2.28), whereas among cohort studies a null association was found (RR = 1.02, 95% CI: 0.96-1.08). For bladder cancer, a nonsignificant association was observed in both case-control (RR = 1.59, 95% CI: 0.95-2.64) and cohort studies (RR = 1.03, 95% CI: 0.86-1.24). Pooled RR from 3 case-control studies displayed a statistically significant association between the DII and risk of kidney cancer (RR = 1.27, 95% CI: 1.03-1.56). Although DII was positively associated with all types of UC, no association was found for EDIP. The present meta-analysis confirmed that an inflammatory diet has a direct effect on the development of prostate cancer and kidney cancer. Large-scale studies are needed to demonstrate the association between dietary inflammatory potential and risk of UC and provide effective nutritional advice for UC prevention. PROTOCOL REGISTRATION: The protocol was registered in the International Prospective Register of Systematic Reviews (CRD42023391204).

Lower intensity of physical activity strengthens the effect of dietary inflammatory index on the risk of all-cause and cause-specific mortality

To examine the independent and joint associations of dietary inflammation index (DII) and physical activity (PA) with mortality risk. We analyzed data for 20,165 study participants aged ≥ 18 from The Rural Chinese Cohort Study. The Cox proportional hazard model was used to calculate the hazard ratio (HR) and 95% confidence interval (CI) of mortality associated with DII and PA. The dose-response association between DII and mortality risk was intuitively generated by the restricted cubic splines model. During the mean 5.03-year follow-up, a total of 1110 cases of all-cause mortality were identified. Compared with people in quartile 1 of DII, positive associations were found in quartile 4 for all-cause (HR 1.27; 95%CI 1.06-1.52), CVD (HR 1.45; 95%CI 1.09-1.91), and other mortality (HR 1.52; 95%CI 1.10-2.09), while a linear association was demonstrated. Compared with people of quartile 1 of DII and high intensity of PA, those with quartile 4 of DII and low intensity of PA had higher risk of all-cause (HR 1.96; 95%CI 1.50-2.56), CVD (HR 2.68; 95%CI 1.71-4.19), and other mortality (HR 1.83; 95%CI 1.19-2.83). A pro-inflammatory diet was significantly associated with increased risk of mortality and lower PA may strengthen the effect.

Association between dietary inflammatory index and cognitive impairment: A meta-analysis

Aims

Cognitive impairment is an increasingly urgent global public health challenge. Dietary Inflammatory Index (DII) is a literature-derived score that links diet to inflammation. The relationship between DII and cognitive impairment remains controversial. Therefore, our study aimed to analysis the role of DII on the risk of cognitive impairment by meta-analysis.

Methods

PubMed, Cochrane Library, MEDLINE, Web of Science and EMBASE databases were searched up to July 2022. Newcastle-Ottawa scale (NOS) and Joanna Briggs Institute (JBI) Checklist were performed to estimate the quality of studies.

Results

Nine observational studies with 19,379 subjects were included. Our study found that higher DII could elevate the risk of cognitive impairment (OR = 1.46, 95%CI = 1.26, 1.69). Meanwhile, the OR of cognitive impairment was 1.49 (95%CI = 1.21, 1.83) for cross-sectional studies and 1.42 (95%CI = 1.12, 1.79) for cohort studies, respectively.

Conclusion

Our meta-analysis indicated that higher DII (indicating a more pro-inflammatory diet) is related to increased risk of cognitive impairment.

Association between the Dietary Inflammatory Index and Gastric Disease Risk: Findings from a Korean Population-Based Cohort Study

Evidence suggests that diets with high pro-inflammatory potential may play a substantial role in the origin of gastric inflammation. This study aimed to examine the association between the energy-adjusted dietary inflammatory index (E-DIITM) and gastric diseases at baseline and after a mean follow-up of 7.4 years in a Korean population. A total of 144,196 participants from the Korean Genome and Epidemiology Study_Health Examination (KoGES_HEXA) cohort were included. E-DII scores were computed using a validated semi-quantitative food frequency questionnaire. Multivariate logistic regression and Cox proportional hazards regression were used to assess the association between the E-DII and gastric disease risk. In the prospective analysis, the risk of developing gastric disease was significantly increased among individuals in the highest quartile of E-DII compared to those in the lowest quartile (HRquartile4vs1 = 1.22; 95% CI = 1.08–1.38). Prospective analysis also showed an increased risk in the incidence of gastritis (HRquartile4vs1 = 1.19; 95% CI = 1.04–1.37), gastric ulcers (HRquartile4vs1 = 1.47; 95% CI = 1.16–1.85), and gastric and duodenal ulcers (HRquartile4vs1 = 1.46; 95% CI = 1.17–1.81) in the highest E-DII quartile compared to the lowest quartile. In the cross-sectional analysis, the E-DII score was not associated with the risk of gastric disease. Our results suggest that a pro-inflammatory diet, indicated by high E-DII scores, is prospectively associated with an increased risk of gastric diseases. These results highlight the significance of an anti-inflammatory diet in lowering the risk of gastric disease risk in the general population.

A new mathematical approach to improve the original dietary inflammatory index (DII) calculation

Accumulating evidence links dietary intake to inflammatory processes involved in non-communicable disease (NCD) development. The dietary inflammatory index (DII) designed by Shivappa et al. has been shown to capture the inflammatory potential of dietary behavior in a large number of epidemiological studies. Thus, the DII may serve as future tool to assess someone’s nutritional inflammatory capacities and hence, the individual risks for NCD development later in life. The calculation method of the DII, however, can benefit from alternative mathematical steps, particularly regarding the transformation from standardized daily food consumption to percentile scores. Here, we provide novel approaches, the scaling-formula (SF) and scaling-formula with outlier detection (SFOD) methods, with the aim to optimize the DII calculation method proposed by Shivappa and colleagues. We illustrate on simulated data specific limitations of the original DII calculation and show the benefits of the SF/SFOD by using simulated data and data from the prospective TEENDIAB study cohort, which supports the application of SF/SFOD in future epidemiological and clinical studies.

Inflammatory Potential of Diet Is Associated with Biomarkers Levels of Inflammation and Cognitive Function among Postmenopausal Women

In postmenopausal women (PW), estrogen depletion may predispose to cognitive decline through an increased risk of chronic inflammation. Unhealthy diets also appear to have an impact on the cognitive health of these women. The aim of this study was to investigate the association between inflammatory potential of the diet, levels of inflammatory biomarkers, and cognitive function in PW. In a population of 222 PW, energy intake-adjusted Dietary Inflammatory Index (E-DII) was used to assess the dietary inflammatory potential. Cognitive function was estimated using the Polish version of Mini-Mental State Examination (MMSE), corrected by age and educational level. Selected biochemical inflammatory markers (C-reactive protein, CRP; interleukin-6, IL-6; and tumor necrosis factor alpha, TNF-α) were measured by ELISA tests. PW with an anti-inflammatory diet (first tercile) had significantly higher MMSE, while BMI, percentage fat mass and TNFα concentration were significantly lower compared to those with the most proinflammatory diets (third tercile). Women with cognitive impairment had significantly higher IL-6 concentrations (4.1 (0.8) pg/mL vs. 2.5 (0.2) pg/mL, p = 0.004), and were less educated (12.7 (0.7) years vs. 14.1 (0.2) years, p = 0.03) and less physically active compared to cognitively normal women. PW with the most proinflammatory diets had increased odds of cognitive impairment compared to those with the most anti-inflammatory diets, even after adjustment (OR = 11.10, 95% confidence level; 95%CI: 2.22; 55.56; p = 0.002). Each one-point increase in E-DII (as a continuous value) was also associated with 1.55-times greater odds of cognitive impairment (95%Cl: 1.19; 2.02 p = 0.003) in this population. Dietary inflammation may increase the risk of cognitive impairment in PW, but future studies should include a more sensitive battery of tests to assess cognitive function in this population. Implementation of an anti-inflammatory dietary pattern in PW may help prevent cognitive decline.

Familial adenomatous polyposis and changes in the gut microbiota: New insights into colorectal cancer carcinogenesis

Patients with familial adenomatous polyposis (FAP), an autosomal dominant hereditary colorectal cancer syndrome, have a lifetime risk of developing cancer of nearly 100%. Recent studies have pointed out that the gut microbiota could play a crucial role in the development of colorectal adenomas and the consequent progression to colorectal cancer. Some gut bacteria, such as Fusobacterium nucleatum, Escherichia coli, Clostridium difficile, Peptostreptococcus, and enterotoxigenic Bacteroides fragilis, could be implicated in colorectal carcinogenesis through different mechanisms, including the maintenance of a chronic inflammatory state, production of bioactive tumorigenic metabolites, and DNA damage. Studies using the adenomatous polyposis coliMin/+ mouse model, which resembles FAP in most respects, have shown that specific changes in the intestinal microbial community could influence a multistep progression, the intestinal "adenoma-carcinoma sequence", which involves mucosal barrier injury, low-grade inflammation, activation of the Wnt pathway. Therefore, modulation of gut microbiota might represent a novel therapeutic target for patients with FAP. Administration of probiotics, prebiotics, antibiotics, and nonsteroidal anti-inflammatory drugs could potentially prevent the progression of the adenoma-carcinoma sequence in FAP. The aim of this review was to summarize the best available knowledge on the role of gut microbiota in colorectal carcinogenesis in patients with FAP.

Dietary Inflammatory Index and Ovarian Cancer Risk: A Meta-Analysis

Existing evidence suggests diet and chronic inflammation as risk factors in ovarian cancer (OC) development. We aim to conduct a meta-analysis exploring possible associations between dietary inflammatory potential and OC. A systematic search was conducted through PubMed, Scopus, Embase, and PMC databases for studies reporting relationships between dietary inflammatory potential and OC risk published up to September 2020. We included six studies for stepwise analysis, of which 5,468 among 197,086 individuals developed OC. Pooled odds ratios (ORs) were calculated by fixed-effects models, while heterogeneity was assessed by Q test and I² statistic. The results revealed a positive association between dietary inflammatory potential measured by the Dietary Inflammatory Index (DII) and OC(P < 0.05). Individuals with higher DII scores had a 42% increased risk of OC incidence [OR = 1.42, 95% confidence interval (CI): 1.19-1.65]. The analysis considering DII as a continuous variable showed an increased risk of 10% for 1-point increase of DII(OR = 1.10, 95% CI: 1.06-1.14). Subgroup analysis revealed that increased risk of OC in individuals with higher DII scores vs. those with lower DII was only significant among post-menopausal women(OR = 1.72, 95% CI: 1.26-2.21) rather than those pre/peri-menopausal(OR = 1.21, 95% CI: 0.63-1.79). Pro-inflammatory diets with higher DII score were significantly related to increased OC risk among post-menopausal women.

TNF genetic polymorphism (rs1799964) may modify the effect of the dietary inflammatory index on gastric cancer in a case-control study

The inflammatory process is known to increase the risk of gastric carcinogenesis, and both genetic and dietary factors are associated with inflammation. In the present study of 1,125 participants (373 cases and 752 controls), we determined whether the dietary inflammatory index (DII) is associated with the risk of gastric cancer (GC) and investigated whether a TNF polymorphism (rs1799964) modifies this association. Semi-quantitative food frequency questionnaire derived data were used to calculate the DII scores. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using multivariable logistic models adjusted for confounders. When we stratified the data by sex, the association between GC and the DII was significant only among the women (OR, 2.27; 95% CI 1.25-4.19), and the DII effect on the risk of GC differed depending on the TNF genotype (OR, 2.30; 95% CI 1.27-4.24 in TT genotype; OR, 0.78; 95% CI 0.37-1.65 in CC + CT, p for interaction = 0.035). Furthermore, the association between the DII and GC was significant in the Helicobacter pylori-positive group; similarly, the effect differed based on the TNF genotype (OR, 1.76; 95% CI 1.13-2.73 in TT genotype; OR,0.98; 95% CI 0.54-1.77 in CT + CC, p for interaction = 0.034). In conclusion, rs1799964 may modify the effect of the DII on GC.