To design and develop a literature-derived, population-based dietary inflammatory index (DII) to compare diverse populations on the inflammatory potential of their diets.
Peer-reviewed primary ...research articles published through December 2010 on the effect of diet on inflammation were screened for possible inclusion in the DII scoring algorithm. Qualifying articles were scored according to whether each dietary parameter increased (+1), decreased (-1) or had no (0) effect on six inflammatory biomarkers: IL-1β, IL-4, IL-6, IL-10, TNF-α and C-reactive protein.
The Dietary Inflammatory Index Development Study was conducted in the Cancer Prevention and Control Program of the University of South Carolina in Columbia, SC, USA from 2011 to 2012.
A total of ≈6500 articles published through December 2010 on the effect of dietary parameters on the six inflammatory markers were screened for inclusion in the DII scoring algorithm. Eleven food consumption data sets from countries around the world were identified that allowed individuals' intakes to be expressed relative to the range of intakes of the forty-five food parameters observed across these diverse populations. Qualifying articles (n 1943) were read and scored based on the forty-five pro- and anti-inflammatory food parameters identified in the search. When fit to this composite global database, the DII score of the maximally pro-inflammatory diet was +7·98, the maximally anti-inflammatory DII score was -8·87 and the median was +0·23.
The DII reflects both a robust literature base and standardization of individual intakes to global referent values. The success of this first-of-a-kind attempt at relating intakes of inflammation-modulating foods relative to global norms sets the stage for use of the DII in a wide variety of epidemiological and clinical studies.
To perform construct validation of the population-based Dietary Inflammatory Index (DII) using dietary data from two different dietary assessments and serum high-sensitivity C-reactive protein ...(hs-CRP) as the construct validator.
Using data derived from (i) three 24 h dietary recalls (24HR) at baseline and at the end of each subsequent quarter (i.e. up to fifteen over a year) and (ii) a 7 d dietary recall (7DDR) measured at baseline and then quarterly, regression analyses were conducted to test the effect of the DII score on serum hs-CRP as dichotomous (≤3 mg/l, >3 mg/l), while controlling for important potential confounders.
Existing data from the Seasonal Variation of Blood Cholesterol Study (SEASONS), a longitudinal observational study of healthy participants recruited in Worcester, MA, USA and participants were followed for 1 year.
Participants who had at least one hs-CRP measurement over her/his 1-year participation (n 495 for 24HR, n 559 for 7DDR).
Higher DII scores were associated with values of hs-CRP >3 mg/l (OR = 1·08; 95 % CI 1·01, 1·16, P = 0·035 for the 24HR; and OR = 1·10; 95 % CI 1·02, 1·19, P = 0·015 for the 7DDR).
The population-based DII was associated with interval changes in hs-CRP using both the 24HR and 7DDR. The success of this first-of-a-kind attempt at relating individuals' intakes of inflammation-modulating foods using this refined DII, and the finding that there is virtually no drop-off in predictive capability using a structured questionnaire in comparison to the 24HR standard, sets the stage for use of the DII in a wide variety of other epidemiological and clinical studies.
The literature on the role of inflammation in health has grown exponentially over the past several decades. Paralleling this growth has been an equally intense focus on the role of diet in modulating ...inflammation, with a doubling in the size of the literature approximately every 4 y. The Dietary Inflammatory Index (DII) was developed to provide a quantitative means for assessing the role of diet in relation to health outcomes ranging from blood concentrations of inflammatory cytokines to chronic diseases. Based on literature from a variety of different study designs ranging from cell culture to observational and experimental studies in humans, the DII was designed to be universally applicable across all human studies with adequate dietary assessment. Over the past 4 y, the DII has been used in >200 studies and forms the basis for 12 meta-analyses. In the process of conducting this work, lessons were learned with regard to methodologic issues related to total energy and nutrient intake and energy and nutrient densities. Accordingly, refinements to the original algorithm have been made. In this article we discuss these improvements and observations that we made with regard to misuse and misinterpretation of the DII and provide suggestions for future developments.
Diet and chronic inflammation of the colon have been suggested to be risk factors in the development of colorectal cancer (CRC). The possible link between inflammatory potential of diet, measured ...through the Dietary Inflammatory Index (DII
), and CRC has been investigated in several populations across the world. The aim of this study was to conduct a meta-analysis on studies exploring this association. Data from nine studies were eligible, of which five were case-control and four were cohort studies. Results from meta-analysis showed a positive association between increasing DII scores, indicating a pro-inflammatory diet, and CRC. Individuals in the highest versus the lowest (reference) DII category showed an overall 40% increased risk of CRC with moderate evidence of heterogeneity relative risk (RR) = 1.40, 95% confidence interval (CI): 1.26, 1.55;
² = 69%,
< 0.001. When analyzed as a continuous variable, results showed an increased risk of CRC of 7% for a 1-point increase in the DII score. Results remained unchanged when analyses were restricted to the four prospective studies. Results of our meta-analysis support the importance of adopting a healthier anti-inflammatory diet in preventing CRC. These results further substantiate the utility of DII as tool to characterize the inflammatory potential of diet and to predict CRC.
Background
Various dietary components have been studied in relation to overall mortality; however, little is known about the relationship between the inflammatory potential of overall diet and ...mortality.
Materials and methods
We examined the association between the dietary inflammatory index (DII) and mortality in the National Health and Nutrition Examination Survey III follow-up study. The DII was computed from baseline dietary intake assessed using 24-h dietary recalls (1988–1994). Mortality was determined from the National Death Index records through 2006. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95 % confidence interval (95 % CI). During the follow-up, 2795 deaths were identified, including 1233 due to cardiovascular disease (CVD), and 615 due to cancer, 158 of which were due to digestive-tract cancers.
Results
Multivariate Cox proportional hazards regression analyses, adjusting for age, race, diabetes status, hypertension, physical activity, body mass index, poverty index, and smoking, revealed positive associations between higher DII scores and mortality. Comparing subjects in DII tertile 3 versus tertile 1, significant associations were noted for all-cause mortality (HR
Tertile3vs1
1.34; 95 % CI 1.19–1.51,
P
trend
< 0.0001), CVD mortality (HR
Tertile3vs1
1.46; 95 % CI 1.18–1.81,
P
trend
= 0.0006), cancer mortality (HR
Tertile3vs1
1.46; 95 % CI 1.10–1.96,
P
trend
= 0.01), and digestive-tract cancer mortality (HR
Tertile3vs1
2.10; 95 % CI 1.15–3.84,
P
trend
= 0.03).
Conclusion
These results indicate that a pro-inflammatory diet, as indicated by higher DII scores, was associated with higher risk of all-cause, CVD, and cancer mortality.
Diet is known to play a key role in atherogenesis and in the development of cardiovascular events. Dietary factors may mediate these processes acting as potential modulators of inflammation. ...Potential Links between inflammatory properties of diet and the occurrence of cardiovascular events have not been tested previously.
We aimed to assess the association between the dietary inflammatory index (DII), a method to assess the inflammatory potential of the diet, and incident cardiovascular disease.
In the prospective, dynamic SUN cohort, 18,794 middle-aged, Spanish university graduates were followed up for 8.9 years (median). A validated 136-item food-frequency questionnaire was used to calculate the DII. The DII is based on scientific evidence about the relationship between diet and inflammatory biomarkers (C-reactive protein, IL-1β, IL-4, IL-6, IL-10 and TNF-α). Cox proportional hazard models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between the DII and incident cardiovascular disease (myocardial infarction, stroke or cardiovascular death).
The risk for cardiovascular events progressively increased with each increasing quartile of DII (ptrend = 0.017). The multivariable-adjusted HR for participants in the highest (most pro-inflammatory) vs. the lowest quartile of the DII was 2.03 (95% CI 1.06-3.88).
A pro-inflammatory diet was associated with a significantly higher risk for developing cardiovascular events.
Scope
Leukocyte telomere length (LTL) is an important biomarker of aging. This study examined whether inflammatory potential of diet, as measured by the Dietary Inflammatory IndexTM (DII) has an ...impact on telomere shortening in the National Health and Nutrition Examination Survey (NHANES). We also carried out validation of the DII with C‐reactive protein (CRP).
Methods and results
Data came from NHANES 1999–2002. LTL and CRP were assayed from leukocyte DNA and serum specimens, respectively. The DII was calculated from food intakes assessed using 24‐h dietary recalls and expressed per 1000 calories consumed. Associations were examined using survey‐based multivariable linear regression for log‐transformed LTL. After multivariable adjustment, higher DII scores (i.e. relatively more pro inflammatory) were associated with shorter LTL both when used as continuous (b = –0.003; 95% confidence interval CI = –0.005, –0.0002) and as quartiles (bDIIquartile4vs1 = –0.013; 95% CI = –0.025, –0.001; Ptrend = .03). In this same sample the DII also was associated with CRP ≥3 mg/L (ORDIIcontinuous = 1.10; 95% CI = 1.06, 1.16).
Conclusion
In these NHANES data there was an association between DII and LTL. This study also provided a successful construct validation of the DII using CRP in a nationally representative sample. These results are consistent with the hypothesis that diet‐associated inflammation determines LTL.
Telomeres are distinctive structures found at the ends of our chromosomes which shorten with age and diet along with inflammation play an important role in the rate of shortening. A pro‐inflammatory diet as evidenced by higher DII scores is associated with increased levels of serum C‐reactive protein and decreased leukocyte telomere length in NHANES 1999–2002. Hence, a diet rich in anti‐inflammatory components like green leafy vegetables and poor in pro‐inflammatory components like red meat and sugary drinks may play an important role in preventing LTL reduction.
Abstract
Background
Diet is considered as one of the modifiable factors that appears to exert a vital role in psychological status. In this way, we designed this study to examine the association ...between dietary inflammatory index (DII), dietary antioxidant index (DAI), and mental health in female adolescents.
Methods
This cross-sectional study included 364 female adolescents selected from high schools in the five regions of Tabriz, Iran. A 3-day food record was used to extract the dietary data and calculate DII/DAI scores. DII and DAI were estimated to assess the odds of depression, anxiety, and stress based on the Depression Anxiety Stress Scales-21. Adjusted relationships of the DII and DAI with depression, anxiety, and stress were determined using multiple regression after adjusting for age, energy intake, BMI, family income and mother and father education. Overweight was defined as body mass index (BMI)-for-age > + 1 z-score relative to world health organization standards.
Results
Depression, anxiety, and stress were observed in 21.4%, 26.6%, and 25.7% of subjects, respectively. The percentage of overweight among adolescents was 19.4%. The association between DII and score of mental health profile was positive among subjects in the third tertile of DII compared to subjects in the first tertile. However, this association was not statistically significant after adjusting for confounding variables. Moreover, there was a significant inverse association between DAI and depression and anxiety; and a statistically insignificant association between DAI and stress after adjusting for confounders.
Conclusions
Our results highlighted the importance of a healthy and anti-inflammatory diet on mental health in female adolescents. Therefore, modifying unhealthy dietary habits are likely to be effective in the management of psychosocial disorders.