Diet quality indices (DQIs) are tools used to evaluate the overall diet quality against dietary guidelines or known healthy dietary patterns. This review aimed to evaluate DQIs and their validation processes to facilitate decision making in the selection of appropriate DQI for use in Australian contexts. A search of CINAHL, PubMed and Scopus electronic databases was conducted for studies published between January 2010 and May 2020, which validated a DQI, measuring > 1 dimension of diet quality (adequacy, balance, moderation, variety) and was applicable to the Australian context. Data on constructs, scoring, weighting and validation methods (construct validity, criterion validity, reliability and reproducibility) were extracted and summarised. The quality of the validation process was evaluated using COnsensus-based Standards for the selection of health Measurement INstruments Risk of Bias and Joanna Briggs Appraisal checklists. The review identified twenty-seven indices measuring adherence to: national dietary guidelines (n 13), Mediterranean Diet (n 8) and specific population recommendations and chronic disease risk (n 6). Extensiveness of the validation process varied widely across and within categories. Construct validity was the most strongly assessed measurement property, while evaluation of measurement error was frequently inadequate. DQIs should capture multiple dimensions of diet quality, possess a reliable scoring system and demonstrate adequate evidence in their validation framework to support use in the intended context. Researchers need to understand the limitations of newly developed DQIs and interpret results in view of the validation evidence. Future research on DQIs is indicated to improve evaluation of measurement error, reproducibility and reliability.

High-quality diets have been found to be beneficial in preventing long-term weight gain. However, concurrent changes in diet quality and body weight over time have rarely been reported. We examined the association between 10-year changes in diet quality and body weight in the Multiethnic Cohort Study. Analyses included 53 977 African Americans, Native Hawaiians, Japanese Americans, Latinos and Whites, who completed both baseline (1993–1996, 45–69 years) and 10-year follow-up (2003–2008) surveys including a FFQ and had no history of heart disease or cancer. Using multivariable regression, weight changes were regressed on changes in four diet quality indexes, Healthy Eating Index-2015, Alternative Healthy Eating Index-2010, alternate Mediterranean Diet and Dietary Approaches to Stop Hypertension scores. Mean weight change over 10 years was 1·2 (sd 6·8) kg in men and 1·5 (sd 7·2) kg in women. Compared with stable diet quality (< 0·5 sd change), the greatest increase (≥ 1 sd increase) in the diet scores was associated with less weight gain (by 0·55–1·17 kg in men and 0·62–1·31 kg in women). Smaller weight gain with improvement in diet quality was found in most subgroups by race/ethnicity, baseline age and baseline BMI. The inverse association was stronger in younger age and higher BMI groups. Ten-year improvement in diet quality was associated with a smaller weight gain, which varied by race/ethnicity and baseline age and BMI. Our findings suggest that maintaining a high-quality diet and improving diet quality over time may prevent excessive weight gain.

The aim of this study was to assess the ability of the FFQ to describe reliable and valid dietary pattern (DP) scores. In a total of 134 participants of the European Prospective Investigation into Cancer and Nutrition-Potsdam study aged 35–67 years, the FFQ was applied twice (baseline and after 1 year) to assess its reliability. Between November 1995 and March 1997, twelve 24-h dietary recalls (24HDR) as reference instrument were applied to assess the validity of the FFQ. Exploratory DP were derived by principal component analyses. Investigated predefined DP were the Alternative Healthy Eating Index (AHEI) and two Mediterranean diet indices. From dietary data of each FFQ, two exploratory DP were retained, but differed in highly loading food groups, resulting in moderate correlations (r 0·45–0·58). The predefined indices showed higher correlations between the FFQ (r(AHEI) 0·62, r(Mediterranean Diet Pyramid Index (MedPyr)) 0·62 and r(traditional Mediterranean Diet Score (tMDS)) 0·51). From 24HDR dietary data, one exploratory DP retained differed in composition to the first FFQ-based DP, but showed similarities to the second DP, reflected by a good correlation (r 0·70). The predefined DP correlated moderately (r 0·40–0·60). To conclude, long-term analyses on exploratory DP should be interpreted with caution, due to only moderate reliability. The validity differed extensively for the two exploratory DP. The investigated predefined DP showed a better reliability and a moderate validity, comparable to other studies. Within the two Mediterranean diet indices, the MedPyr performed better than the tMDs in this middle-aged, semi-urban German study population.

Telomeres are nucleoprotein complexes that form the ends of eukaryotic chromosomes where they protect DNA from genomic instability, prevent end-to-end fusion and limit cellular replicative capabilities. Increased telomere attrition rates, and relatively shorter telomere length, is associated with genomic instability and has been linked with several chronic diseases, malignancies and reduced longevity. Telomeric DNA is highly susceptible to oxidative damage and dietary habits may make an impact on telomere attrition rates through the mediation of oxidative stress and chronic inflammation. The aim of this study was to examine the association between leucocyte telomere length (LTL) with both the Dietary Inflammatory Index® 2014 (DII®) and the Alternative Healthy Eating Index 2010 (AHEI-2010). This is a cross-sectional analysis using baseline data from 263 postmenopausal women from the Alberta Physical Activity and Breast Cancer Prevention (ALPHA) Trial, in Calgary and Edmonton, Alberta, Canada. No statistically significant association was detected between LTL z-score and the AHEI-2010 (P = 0·20) or DII® (P = 0·91) in multivariable adjusted models. An exploratory analysis of AHEI-2010 and DII® parameters and LTL revealed anthocyanidin intake was associated with LTL (P < 0·01); however, this association was non-significant after a Bonferroni correction was applied (P = 0·27). No effect modification by age, smoking history, or recreational physical activity was detected for either relationship. Increased dietary antioxidant and decreased oxidant intake were not associated with LTL in this analysis.

No study is available that has assessed the association of dietary diversity score (DDS) and alternative healthy eating index (AHEI) with glioma. The present study aimed to assess this association in Iranian adults. Overall, 128 pathologically confirmed cases of glioma were enrolled from hospitals and 256 age- and sex-matched controls were recruited from other wards of the hospital between 2009 and 2011. Dietary assessment was done using a validated block-format 123-item semi-quantitative FFQ. Dietary indices including DDS and AHEI-2010 were constructed according to standard methods. After controlling for potential confounders, a significant inverse association was found between DDS and risk of glioma (OR 0·42, 95 % CI 0·19, 0·94). Such finding was also seen when further adjustment was made for BMI; such that participants in the highest quartile of DDS were 56 % less likely to have glioma compared with those in the lowest quartile (OR 0·44, 95 % CI, 0·20, 0·97). In addition, a significant inverse association was found between adherence to AHEI and glioma; such that in the fully adjusted model, participants in the fourth quartile of AHEI had 74 % lower risk of glioma compared with those in the first quartile (OR 0·26, 95 % CI 0·12, 0·56). In conclusion, we found that greater adherence to the healthy, as measured by AHEI, and diverse, as measured by DDS, diets was associated with decreased odds of glioma.

The consumption of nitrate-rich vegetables can acutely lower blood pressure and improve mediators shown to optimise vascular health. However, we do not yet understand the impact of long-term habitual dietary nitrate intake and its association with CVD. Therefore, the aim of this investigation was to examine the relationship between habitual dietary nitrate intakes and risk of CHD in women from the Nurses’ Health Study. We prospectively followed 62 535 women who were free from diabetes, CVD and cancer at baseline in 1986. Information on diet was updated every 4 years with validated FFQ. The main outcome was CHD defined by the occurrence of non-fatal myocardial infarction or fatal CHD. Cox proportional hazard regression models were used to estimate the relative risks (RR) and 95 % CI. During 26 years of follow-up, 2257 cases of CHD were identified. When comparing the highest quintile of nitrate intake with the lowest quintile, in aged-adjusted analysis there was a protective association for CHD (RR=0·77, 95 % CI 0·68, 0·97; P=0·0002) which dissipated after further adjustment for smoking, physical activity, BMI and race (RR=0·91; 95 % CI 0·80, 1·04; P=0·27). This magnitude of association was further attenuated once we adjusted for the Alternative Healthy Eating Index excluding vegetable and fruit consumption (RR=1·04, 95 % CI 0·91, 1·20; P=0·34). Dietary nitrate intake was not related to the risk of CHD after adjustment for other lifestyle and non-vegetable dietary factors in a large group of US women.

The internet has considerable potential to improve health-related food choice at low-cost. Online solutions in this field can be deployed quickly and at very low cost, especially if they are not dependent on bespoke devices or offline processes such as the provision and analysis of biological samples. One key challenge is the automated delivery of personalised dietary advice in a replicable, scalable and inexpensive way, using valid nutrition assessment methods and effective recommendations. We have developed a web-based personalised nutrition system (eNutri) which assesses dietary intake using a validated graphical FFQ and provides personalised food-based dietary advice automatically. Its effectiveness was evaluated during an online randomised controlled trial dietary intervention (EatWellUK study) in which personalised dietary advice was compared with general population recommendations (control) delivered online. The present paper presents a review of literature relevant to this work, and describes the strategies used during the development of the eNutri app. Its design and source code have been made publicly available under a permissive open source license, so that other researchers and organisations can benefit from this work. In a context where personalised diet advice has great potential for health promotion and disease prevention at-scale and yet is not currently being offered in the most popular mobile apps, the strategies and approaches described in the present paper can help to inform and advance the design and development of technologies for personalised nutrition.

Few studies have evaluated the relationships between intake of sugar-sweetened beverages (SSB) and intermediate biomarkers of cardiometabolic risk. Associations between artificially sweetened beverages (ASB) and fruit juice with cardiometabolic biomarkers are also unclear. We investigated habitual SSB, ASB and fruit juice intake in relation to biomarkers of hepatic function, lipid metabolism, inflammation and glucose metabolism. We analysed cross-sectional data from 8492 participants in the Nurses’ Health Study who were free of diabetes and CVD. Multivariate linear regression was used to assess the associations of SSB, ASB and fruit juice intake with concentrations of fetuin-A, alanine transaminase, γ-glutamyl transferase, TAG, HDL-cholesterol, LDL-cholesterol, total cholesterol, C-reactive protein (CRP), intracellular adhesion molecule 1 (ICAM-1), vascular cell adhesion protein 1, adiponectin, insulin and HbA1c as well as total cholesterol:HDL-cholesterol ratio. More frequent intake of SSB was significantly associated with higher concentrations of fetuin-A, TAG, CRP, ICAM-1, adiponectin and insulin, a higher total cholesterol:HDL-cholesterol ratio, and a lower concentration of HDL-cholesterol (Ptrend ranges from <0·0001 to 0·04) after adjusting for demographic, medical, dietary and lifestyle variables. ASB intake was marginally associated with increased concentrations of CRP (Ptrend=0·04) and adiponectin (Ptrend=0·01). Fruit juice intake was associated with increased concentrations of TAG and HbA1c and a lower concentration of adiponectin (Ptrend ranges from <0·0001 to 0·01). In conclusion, habitual intake of SSB was associated with adverse levels of multiple cardiometabolic biomarkers. Associations between ASB and fruit juice with cardiometabolic risk markers warrant further exploration.

Dietary indices have been related to risk for type 2 diabetes (T2D) predominantly in white populations. The present study evaluated this association in the ethnically diverse Multiethnic Cohort and examined four diet quality indices in relation to T2D risk, homoeostatic model assessment-estimated insulin resistance (HOMA-IR) and biomarkers of dyslipidaemia, inflammation and adipokines. The T2D analysis included 166 550 white, African American, Native Hawaiian, Japanese American and Latino participants (9200 incident T2D cases). Dietary intake was assessed at baseline using a quantitative FFQ and T2D status was based on three self-reports and confirmed by administrative data. Biomarkers were assessed about 10 years later in a biomarker subcohort (n 10 060). Sex- and ethnicity-specific hazard ratios were calculated for the Healthy Eating Index-2010 (HEI-2010), the alternative HEI-2010 (AHEI-2010), the alternate Mediterranean diet score (aMED) and the Dietary Approaches to Stop Hypertension (DASH). Multivariable-adjusted means of biomarkers were compared across dietary index tertiles in the biomarker subcohort. The AHEI-2010, aMED (in men only) and DASH scores were related to a 10–20 % lower T2D risk, with the strongest associations in whites and the direction of the relationships mostly consistent across ethnic groups. Higher scores on the four indices were related to lower HOMA-IR, TAG and C-reactive protein concentrations, not related to leptin, and the DASH score was directly associated with adiponectin. The AHEI-2010 and DASH were directly related to HDL-cholesterol in women. Potential underlying biological mechanisms linking diet quality and T2D risk are an improved lipid profile and reduced systemic inflammation and, with regards to DASH alone, an improved adiponectin profile.

Earlier studies have shown a protective association between adherence to healthy eating guidelines and mental disorders in Western nations; however, data in this regard are limited from the understudied region of Middle East. We examined the association between adherence to healthy eating guidelines, as measured by Alternative Healthy Eating Index (AHEI)-2010, and prevalence of anxiety and depression in a large sample of Iranian adults. In this cross-sectional study, data on dietary intakes of 3363 adult participants were collected using a validated dish-based 106-item semi-quantitative FFQ. Adherence to healthy eating was quantified using AHEI-2010, as suggested by earlier publications. The Iranian validated version of Hospital Anxiety and Depression Scale was used to assess anxiety and depression in study participants. Data on other covariates were gathered using a pre-tested questionnaire. Overall, the prevalence of anxiety and depression was 15·2 % (males 10·8 % and females 18·3 %) and 30·0 % (males 22·9 % and females 35·1 %), respectively. After controlling for potential confounders, those in the top quartile of AHEI-2010 had a 49 % lower chance of anxiety (OR 0·51; 95 % CI 0·35, 0·72) and a 45 % lower odds of depression (OR 0·55; 95 % CI 0·42, 0·72), compared with those in the bottom quartile. Stratified analysis by sex revealed that women in the highest categories of AHEI-2010 had a 49 % lower odds of having anxiety and depression, after adjustment for confounders, but no significant association was found in men. In addition, among individuals who were 40 years old or younger, those with high adherence to AHEI-2010 were 58 and 51 % less likely to have anxiety and depression, compared with those with less adherence. Adherence to healthy eating was inversely associated with a lower chance of anxiety and depression in Iranian adults. Prospective studies are required to confirm these associations in Middle-Eastern populations.