Profiles of a healthful diet and its relationship to biomarkers in a population sample from Mediterranean southern France

Adherence to Mediterranean dietary quality index and risk of breast cancer in adult women: a case-control study

BACKGROUND

Breast cancer (BC) is the fifth most prevalent cause of cancer-related deaths in Iran. Given that the role of whole-diet on cancer risk is important, this study aimed to assess the association of MedDQI and breast cancer risk.

METHODS

This hospital-based case-control study was performed on 150 women with pathologically confirmed breast cancer within the period of less than 3 months. Controls were 150 apparently healthy that were matched by age. Dietary data was collected using a validated questionnaire. To examine participants' adherence to MedDQI, the MedDQI was created according to foods and nutrients highlighted or minimized in the MedDQI construction.

RESULTS

After adjusting for possible confounders, participants in the highest quartile of the MedDQI score had 55% lower odds of breast cancer than women in the bottom quartile (OR: 0.45, 95% CI: 0.21, 0.94, P trend: 0.02). Stratified analysis by menopausal status showed such association in postmenopausal women (OR: 0.24, 95% CI: 0.07, 0.8, P trend: 0.055) after controlling for age and energy intake.

CONCLUSION

The results showed an inverse association between adherence to the MedDQI and risk of breast cancer among Iranian women. More prospective studies are needed to confirm our results.

Comparison and convergent validity of five Mediterranean dietary indexes applied to Brazilian adults and older adults: data from a population-based study (2015 ISA-Nutrition)

Different dietary indexes are proposed to investigate adherence to the Mediterranean diet (MD). However, they are based on different methodologies, and limited research has compared them to each other, particularly in non-Mediterranean populations. We aimed to compare five indexes intended to measure adherence to the MD. The sample was composed of adults and older adults (n 1187) from 2015 ISA-Nutrition, a cross-sectional population-based study in São Paulo, SP, Brazil. Dietary data obtained through two 24-h dietary recalls (24HDR) from which the Mediterranean diet scale (MDS), Mediterranean diet Score (MedDietscore), Mediterranean dietary pattern (MDP), Mediterranean Adequacy Index (MAI) and Mediterranean-Style Dietary Pattern Score (MSDPS) were calculated. The correlations and agreements between them were analysed by Spearman's correlation and linearly weighted Cohen's Kappa coefficients, respectively. Confirmatory factor analyses (CFAs) were applied to investigate their convergent validity. The highest correlations were found between MDP and MAI (r = 0⋅76; 95% CI 0⋅74-0⋅79) and between MDP and MDS (r = 0⋅72; 95% CI 0⋅69-0⋅75). The greatest agreements observed were moderate, between MDP v. MAI (κ = 0⋅57, P < 0⋅001) and MDP v. MDS (κ = 0⋅48, P < 0⋅001). The goodness-of-fit of CFA for MedDietscore (RMSEA = 0⋅033, 90% CI 0⋅02-0⋅042; SRMR = 0⋅042) and MSDPS (RMSEA = 0⋅028, 90% CI 0⋅019-0⋅037; SRMR = 0⋅031) had acceptable values for absolute fit indices. Vegetables, olive oil, MUFA:SFA ratio and cereals with legumes were more relevant to characterise the MD (factor loadings ≥0⋅50). The MDS, MAI and MDP classified the population similarly, but the MedDietscore showed better performances in evaluating adherence to the MD. These results provided guidance for the most appropriate Mediterranean dietary index to be applied in non-Mediterranean populations.

Association of the Mediterranean Dietary Quality Index with handgrip strength and muscle endurance: A cross-sectional study

Mediterranean diet is a healthy eating pattern associated with various health advantages. Different scoring methods of adherence to this diet have been used to investigate the association between the Mediterranean diet and muscle outcomes. The present study aimed to investigate the association of the Mediterranean Dietary Quality Index (Med-DQI) with handgrip strength (HS) and muscle endurance (ME). The current cross-sectional study involved 268 Iranian adults aged 18-70 years. Anthropometric measures were evaluated. We used the 168-item food frequency questionnaire (FFQ) to develop the Med-DQI score. The Med-DQI score ranges from 0 to 14 (lower score suggests higher adherence to Mediterranean diet). HS was measured by a digital handgrip dynamometer, and ME was the amount of time to reach a maximum of 50% of grip strength. Multiple regression analysis was used to determine the association of Med-DQI and its components with HS and ME. Med-DQI score was not associated with mean handgrip strength (MHS) (p = .34) and mean muscle endurance (MME) (p = .69) in the crude model. The associations remained insignificant after the adjustment of covariates (p = .16, .31, respectively). Among the components of Med-DQI, cholesterol, meats, fish, and cereals were positively correlated with MHS (p < .001 for all). Meats (p = .02), olive oil (p < .001), cereals (p = .04), fruits and vegetables (p < .001 for all) were also positively correlated with MME. According to our findings, Med-DQI score is not associated with MHS and MME in a population of Iranian adults. Further longitudinal studies are required to confirm these findings.

Diet quality indices and their associations with health-related outcomes in children and adolescents: an updated systematic review

BACKGROUND

To describe a-priori diet quality indices used in children and adolescents, appraise the validity and reliability of these indices, and synthesise evidence on the relationship between diet quality and physical and mental health, and growth-related outcomes.

METHODS

Five electronic databases were searched until January 2019. An a-priori diet quality index was included if it applied a scoring structure to rate child or adolescent (aged 0-18-years) dietary intakes relative to dietary or nutrient guidelines. Diagnostic accuracy studies and prospective cohort studies reporting health outcomes were appraised using the Academy of Nutrition and Dietetics Quality Criteria Checklist.

RESULTS

From 15,577 records screened, 128 unique paediatric diet quality indices were identified from 33 countries. Half of the indices' scores rated both food and nutrient intakes (n = 65 indices). Some indices were age specific: infant (< 24-months; n = 8 indices), child (2-12-years; n = 16), adolescent (13-18 years; n = 8), and child/adolescent (n = 14). Thirty-seven indices evaluated for validity and/or reliability. Eleven of the 15 indices which investigated associations with prospective health outcomes reported significant results, such as improved IQ, quality of life, blood pressure, body composition, and prevalence of metabolic syndrome.

CONCLUSIONS

Research utilising diet quality indices in paediatric populations is rapidly expanding internationally. However, few indices have been evaluated for validity, reliability, or association with health outcomes. Further research is needed to determine the validity, reliability, and association with health of frequently utilised diet quality indices to ensure data generated by an index is useful, applicable, and relevant.

REGISTRATION

PROSPERO number: CRD42018107630 .

Dynamics of Chinese Diet Divergence from Chinese Food Pagoda and Its Association with Adiposity and Influential Factors: 2004-2011

Nutrition transition in China has a strong impact on dietary quality and health of Chinese consumers. This study developed the diet quality divergence Index (DQD), the divergence between real food consumption and the Chinese food pagoda 2016 (CFP), to measure the quality of diet in China. Using four waves of data (2004, 2006, 2009, and 2011) from China Health and Nutrition Survey (CHNS), this study shed light on the transition of diet quality for Chinese residents. Results indicate that the DQD generally decreased and Chinese diet quality improved during 2004-2011. The divergence was mainly caused by over-consumption of legumes and nuts, and under-consumption of milk and milk products. Rising income and urbanization were positively correlated with diet quality for the people with low DQD. However, both of them had negative impacts on diet quality for those with high DQD. Females and rural residents held a lower DQD than their counterparts. The results also revealed that healthy food preference, education, dining at home, household size, proportions of teens (6-17) and elders (over 64) in the families are positively correlated with Chinese diet quality. However, labor intensity, frequency of drinking alcohol, and smoking have negative impacts on diet quality. Moreover, higher DQD was found to be associated with increasing risks of overweight/obesity. Therefore, we suggest national healthy policies should pay more attention to nutrition education. It is also necessary to focus on populations with poor diet quality and to adopt measures to control drinking alcohol and smoking.

Review of a priori dietary quality indices in relation to their construction criteria

A multitude of indices measure the healthiness of dietary patterns. Because validation results with respect to health outcomes do not sufficiently facilitate the choice of a specific dietary quality index, the decision of which index to use for a particular research objective should be based on other criteria. This review aims to provide guidance on which criteria to focus upon when choosing a dietary index for a specific research question. A review of 57 existing specifications of dietary quality indices was conducted, taking explicitly into account relevant construction criteria explicated in the Organisation for Economic Co-operation and Development handbook on constructing composite indicators. Index construction choices regarding the following criteria were extracted: theoretical framework, indicator selection, normalization and valuation functions, and aggregation methods. Preferable features of dietary indices are discussed, and a summarizing toolbox is provided to help identify indices with the most appropriate construction features for the respective study aim and target region and with regard to the available database. Directions for future efforts in the specification of new diet quality indices are given.

Dietary Patterns Characterized by High Meat Consumption Are Associated with Other Unhealthy Life Styles and Depression Symptoms

OBJECTIVE

We aimed to identify dietary patterns (DPs) of Portuguese adults, to assess their socioeconomic, demographic, lifestyle determinants, and to identify their impact on health.

DESIGN

EpiDoC 2 study included 10,153 Portuguese adults from the EpiDoC Cohort, a population-based study. In this study, trained research assistants using computer-assisted telephone interview collected socioeconomic, demographic, dietary, lifestyles, and health information from March 2013 to July 2015. Cluster analysis was performed, based on questions regarding the number of meals, weekly frequency of soup consumption, vegetables, fruit, meat, fish, dairy products, and daily water intake. Factors associated with DP were identified through logistic regression models.

RESULTS

Two DPs were identified: the "meat dietary pattern" and the "fruit & vegetables dietary pattern." After multivariable adjustment, women (OR = 0.52; p < 0.001), older adults (OR = 0.97; p < 0.001), and individuals with more years of education (OR = 0.96; p = 0.025) were less likely to adopt the "meat dietary pattern," while individuals in a situation of job insecurity/unemployment (OR = 1.49; p = 0.013), Azores island residents (OR = 1.40; p = 0.026), current smoking (OR = 1.58; p = 0.001), daily alcohol intake (OR = 1.46; p = 0.023), and physically inactive (OR = 1.86; p < 0.001) were positively and significantly associated with "meat dietary pattern." Moreover, individuals with depression symptoms (OR = 1.50; p = 0.018) and the ones who did lower number of medical appointments in the previous year (OR = 0.98; p = 0.025) were less likely to report this DP.

CONCLUSION

Our results suggest that unhealthy DPs (meat DP) are part of a lifestyle behavior that includes physical inactivity, smoking habits, and alcohol consumption. Moreover, depression symptoms are also associated with unhealthy DPs.

Mediterranean dietary quality index and dietary phytochemical index among patients candidate for coronary artery bypass grafting (CABG) surgery

Background

The aim of the present research was to evaluate the relationship between Mediterranean dietary quality index (Med-DQI) and dietary phytochemical index (DPI) with metabolic risk factors of cardiovascular disease in candidates for coronary artery bypass graft (CABG) surgery.

Methods

This was a cross-sectional study on 454 patients aged 35–80 years as candidates of CABG and hospitalized in Tehran Heart Center. Anthropometric and demographic characteristics were obtained from all participants and a 138-item semi-quantitative food frequency questionnaire (FFQ) was used to evaluate Med-DQI and DPI. Biochemical parameters including HbA1C, serum lipids, albumin, creatinine and C-reactive protein (CRP) were assessed by commercial laboratory methods.

Results

Patients with higher scores of “saturated fatty acids” had lower serum albumin concentrations (P < 0.05). High scores of “cholesterol” subgroup was also accompanied with higher serum Hb A1C percent (P = 0.04). Significantly higher concentrations of serum creatinine were also observed in categorizes with lower “fish” scores. Patients with lower phytochemical intakes had significantly higher Med-DQI scores.

Conclusion

According to our findings, high dietary intakes of saturated fatty acids and cholesterol were associated with low serum albumin and Hb A1C concentration. Further studies are needed to better clarify these associations and possible underlying mechanisms.

Mediterranean dietary pattern and VEGF +405 G/C gene polymorphisms in patients with metabolic syndrome: An aspect of gene-nutrient interaction

Aims

To evaluate the relationship between Mediterranean dietary pattern, anthropometric and metabolic biomarkers and vascular endothelial growth factor (VEGF) +405 G/C gene polymorphism in patient with metabolic syndrome (Mets).

Materials and methods

In this study 150 patients with Mets and 50 healthy subjects were enrolled. Dietary intakes were evaluated with a semi-quantitative food-frequency questionnaire (FFQ) and Mediterranean dietary quality index (Med-DQI) was assessed. Anthropometric assessments and blood pressure measurement were performed. Biochemical assays including fasting serum glucose (FSG), matrix metalloproteinase-3 (MMP-3), liver enzymes and lipid profiles were also assessed. Polymorphism of +405 G/C VEGF gene was determined utilizing polymerase chain reaction-restriction fragments length polymorphism (PCR-RFLP) method.

Results

Serum high density lipoprotein-cholesterol (HDL-C) was significantly lower and low density lipoprotein cholesterol (LDL-C), triglyceride (TG), total cholesterol (TC) concentrations and FSG were significantly higher in metabolic syndrome patients compared with control group (P < 0.05). Metabolic syndrome group with high consumption of “cholesterol” had significantly upper serum TG; also high consumption of “fish” and “vegetables-fruits” was associated with a significantly lower serum LDL concentrations. In metabolic syndrome patients with CC genotype, mean score of “saturated fatty acid” subgroup was significantly higher compared with other genotypes; whereas, in healthy individuals, mean score of “fruit-vegetable” subgroup in individuals of CC and GG genotype was significantly higher (P<0.05).

Conclusion

Our findings indicated a significant relationship between Mediterranean dietary quality index and both anthropometric and metabolic risk factors. We also indicated a higher “saturated fatty acid” intake in CC genotype among metabolic syndrome patients.

Definition of the Mediterranean Diet; a Literature Review

Numerous studies over several decades suggest that following the Mediterranean diet (MedDiet) can reduce the risk of cardiovascular disease and cancer, and improve cognitive health. However, there are inconsistencies among methods used for evaluating and defining the MedDiet. Through a review of the literature, we aimed to quantitatively define the MedDiet by food groups and nutrients. Databases PubMed, MEDLINE, Science Direct, Academic Search Premier and the University of South Australia Library Catalogue were searched. Articles were included if they defined the MedDiet in at least two of the following ways: (1) general descriptive definitions; (2) diet pyramids/numbers of servings of key foods; (3) grams of key foods/food groups; and (4) nutrient and flavonoid content. Quantity of key foods and nutrient content was recorded and the mean was calculated. The MedDiet contained three to nine serves of vegetables, half to two serves of fruit, one to 13 serves of cereals and up to eight serves of olive oil daily. It contained approximately 9300 kJ, 37% as total fat, 18% as monounsaturated and 9% as saturated, and 33 g of fibre per day. Our results provide a defined nutrient content and range of servings for the MedDiet based on past and current literature. More detailed reporting amongst studies could refine the definition further.

Preschool-Adapted Liking Survey (PALS): A Brief and Valid Method To Assess Dietary Quality of Preschoolers

BACKGROUND

Feasible, valid, and reliable tools are needed to assess dietary quality among preschoolers. We aimed to test construct-/criterion-related validity and reliability of a dietary quality index generated from a liking survey and novel dietary patterns for characterizing food hedonism and parental feeding practices.

METHODS

Participants included 416 economically disadvantaged, diverse preschoolers (41% overweight/obese) from educational centers and their parents. Parents completed liking and frequency surveys; the liking survey took half as long to complete. Preschoolers' skin carotenoid status (measured by Resonance Raman spectroscopy) and BMI percentile (measured weight/height) were assessed. The Healthy Eating Preference Index (HEPI) was constructed from weighted averages of liking scores for food groups and healthy variety score and Healthy Eating Index 2010 (HEI) from nutrient analysis of the frequency survey.

RESULTS

The HEPI was normally distributed and showed construct validity and adequate internal reliability. In hierarchical regression analyses, the HEPI explained carotenoid status and adiposity as alternative or value-added predictors to HEI, supporting criterion-related validity of HEPI. Parental reporting of children's liking of high-fat/sweet/salty foods in excess of pleasurable activities (food hedonism) predicted heavier preschoolers, as did discord between HEI and HEPI (potential parental pressure toward healthy eating). HEPI alone or with HEI explained variability in carotenoid status and adiposity in path models with adequate to good fits.

CONCLUSIONS

With simple collection and processing, the liking survey can generate a valid/reliable dietary quality index in child care settings to identify preschoolers at risk for lower nutritional status. Using liking and frequency-based screeners could improve understanding of parental feeding behaviors and precision of predicting nutritional status.

A dietary guideline adherence score is positively associated with dietary biomarkers but not lipid profile in healthy children

BACKGROUND

Whether dietary indexes are associated with biomarkers of children's dietary intake is unclear.

OBJECTIVE

The study aim was to examine the relations between diet quality and selected plasma biomarkers of dietary intake and serum lipid profile.

METHODS

The study sample consisted of 130 children aged 4-13 y (mean ± SD: 8.6 ± 2.9 y) derived by using baseline data from an intervention study. The Dietary Guideline Index for Children and Adolescents (DGI-CA) comprises the following 11 components with age-specific criteria: 5 core food groups, whole-grain bread, reduced-fat dairy foods, discretionary foods (nutrient poor; high in saturated fat, salt, and added sugar), healthy fats/oils, water, and diet variety (possible score of 100). A higher score reflects greater compliance with dietary guidelines. Venous blood was collected for measurements of serum lipids, fatty acid composition, plasma carotenoids, lutein, lycopene, and α-tocopherol. Linear regression was used to examine the relation between DGI-CA score (independent variable) and concentrations of biomarkers by using the log-transformed variable (outcome), controlling for confounders.

RESULTS

DGI-CA score was positively associated (P < 0.05) with plasma concentrations of lutein (standardized β = 0.17), α-carotene (standardized β = 0.28), β-carotene (standardized β = 0.26), and n-3 (ω-3) fatty acids (standardized β = 0.51) and inversely associated with plasma concentrations of lycopene (standardized β = -0.23) and stearic acid (18:0) (standardized β = -0.22). No association was observed between diet quality and α-tocopherol, n-6 fatty acids, or serum lipid profile (all P > 0.05).

CONCLUSION

Diet quality, conceptualized as adherence to national dietary guidelines, is cross-sectionally associated with plasma biomarkers of dietary exposure but not serum lipid profile. This trial was registered with the Australia New Zealand Clinical Trial Registry (www.anztr.org.au) as ACTRN12609000453280.

The Dutch Healthy Diet index as assessed by 24 h recalls and FFQ: associations with biomarkers from a cross-sectional study

The Dutch Healthy Diet index (DHD-index) was developed using data from two 24 h recalls (24hR) and appeared useful to evaluate diet quality in Dutch adults. As many epidemiologic studies use FFQ, we now estimated the DHD-index score using FFQ data. We compared whether this score showed similar associations with participants' characteristics, micronutrient intakes, and biomarkers of intake and metabolism compared with the DHD-index using 24hR data. Data of 121 Dutch participants of the European Food Consumption Validation study were used. Dietary intake was assessed by two 24hR and a 180-item FFQ. Biomarkers measured were serum total cholesterol and carotenoids, EPA + DHA in plasma phospholipids and 24 h urinary Na. A correlation of 0·48 (95 % CI 0·33, 0·61) was observed between the DHD-index score based on 24hR data and on FFQ data. Classification of participants into the same tertiles of the DHD-index was achieved for 57 %. Women showed higher DHD-index scores. Energy intake was inversely associated with both DHD-index scores. Furthermore, age and intakes of folate, Fe, Mg, K, vitamin B6 and vitamin C were positively associated with both DHD-index scores. DHD-index scores showed acceptable correlations with the four combined biomarkers taking energy intake into account (r 24hR 0.55; r FFQ 0.51). In conclusion, the DHD-index score based on FFQ data shows similar associations with participants' characteristics, energy intake, micronutrient intake and biomarkers compared with the score based on 24hR data. Furthermore, ranking of participants was acceptable for both methods. FFQ data may therefore be used to assess diet quality using the DHD-index in Dutch populations.

Evaluating and adapting the Mediterranean diet for non-Mediterranean populations: a critical appraisal

This review outlines the limitations of current techniques for evaluating the Mediterranean diet in Mediterranean versus non-Mediterranean populations. Differences between the two populations with regard to the foods that are available, food processing and preparation techniques, and eating and lifestyle habits may influence the implementation and effects of a Mediterranean diet in non-Mediterranean regions. For example, the composition of food groups may vary significantly, due to differences in the specific foods within a food group and to differences in aspects of food production and preparation. Notable differences between the diets of Mediterranean versus non-Mediterranean populations include the source of monounsaturated fatty acids (olive oil versus meat), the amount of vegetables consumed and their manner of preparation, the source of alcohol (wine versus other) and the pattern of intake, and the types of meat and dairy products consumed. Lifestyle factors such as meal patterns and exposure to sunlight may also act as confounding factors when the overall benefits of a Mediterranean diet are assessed. Improving the calculation of Mediterranean diet scores and measuring plasma nutrient levels may help mitigate the effects of confounders. These considerations could have important health implications when a Mediterranean diet is implemented by non-Mediterranean populations.

Intake and serum profile of fatty acids are weakly correlated with global dietary quality in European adolescents

OBJECTIVE

The present study assessed whether compliance with the Food-Based Dietary Guidelines is related to habitual fatty acid (FA) intake and blood lipid parameters.

METHODS

Dietary information was collected by two non-consecutive 24-h recalls in 1804 European adolescents. Compliance with the Food-Based Dietary Guidelines was expressed by calculating the Diet Quality Index for Adolescents (DQI-A). Blood samples were collected in a randomly selected subset (n = 552). Relations between FA intake/serum concentrations and DQI-A were tested with multilevel regression analysis to correct for the study design (clustering within cities). Analyses were stratified for gender; age was entered as a covariate.

RESULTS

Better DQI-A scores were related to increased proportional intakes of energy from total fat, saturated FA, monounsaturated FA, and cholesterol (P < 0.001), whereas no significant association was observed with polyunsaturated FA intakes. In adolescents with higher compared with lower DQI-A scores, dairy products contributed more (21.0% versus 12.7%) and low-nutrient, energy-dense items contributed less (17.2% versus 26.3%) to the intake of total fat. A positive association was observed between the DQI-A scores and serum concentrations of eicosapentaenoic acid and docosahexaenoic acid (all P < 0.005). The latter, however, was significant only in girls. In boys, higher DQI-A scores were inversely associated with serum cholesterol concentrations (P < 0.05).

CONCLUSION

Although compliance with the Food-Based Dietary Guidelines was not always associated with a favorable FA intake pattern, a significant favorable association with some serum biomarkers was observed. This outcome underlines the importance of considering dietary habits instead of single-nutrient intakes.

Validation of the Diet Quality Index for Adolescents by comparison with biomarkers, nutrient and food intakes: the HELENA study

Food-based dietary guidelines (FBDG) aim to address the nutritional requirements at population level in order to prevent diseases and promote a healthy lifestyle. Diet quality indices can be used to assess the compliance with these FBDG. The present study aimed to investigate whether the newly developed Diet Quality Index for Adolescents (DQI-A) is a good surrogate measure for adherence to FBDG, and whether adherence to these FBDG effectively leads to better nutrient intakes and nutritional biomarkers in adolescents. Participants included 1804 European adolescents who were recruited in the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Study. Dietary intake was assessed by two, non-consecutive 24 h recalls. A DQI-A score, considering the components' dietary quality, diversity and equilibrium, was calculated. Associations between the DQI-A and food and nutrient intakes and blood concentration biomarkers were investigated using multilevel regression analysis corrected for centre, age and sex. DQI-A scores were associated with food intake in the expected direction: positive associations with nutrient-dense food items, such as fruits and vegetables, and inverse associations with energy-dense and low-nutritious foods. On the nutrient level, the DQI-A was positively related to the intake of water, fibre and most minerals and vitamins. No association was found between the DQI-A and total fat intake. Furthermore, a positive association was observed with 25-hydroxyvitamin D, holo-transcobalamin and n-3 fatty acid serum levels. The present study has shown good validity of the DQI-A by confirming the expected associations with food and nutrient intakes and some biomarkers in blood.

Lifestyle factors associated with serum N-3 fatty acid levels in breast cancer patients

Long chain n3 fatty acids appear to have beneficial effects in several domains of health relevant to breast cancer survivors. This study evaluated inter-individual differences in serum levels of n3 fatty acids in 40 breast cancer patients who were participating in a pilot study for prevention of weight gain. Significant predictors of baseline n3 fatty acid levels in serum were dietary intakes of n3 fatty acids, BMI, serum levels of carotenoids and TV hours watched/day, accounting for 43% of the variance. Counseling for prevention of weight gain also tended to increase n3 fatty acid blood levels over time during chemotherapy.

Omega-3 fatty acids and cancers: a systematic update review of epidemiological studies

Experimental models showed consistently a modulation of carcinogenesis by omega 3 polyunsaturated fatty acids (ω3 PUFA). Fish intake is often described as part of a beneficial dietary pattern. However, observational epidemiological studies on the relationship between ω3 PUFA reported conflicting results. The objective of this systematic review is to determine whether there exists any progress in the evaluation of the causal relationship between dietary ω3 PUFA and cancers since the previous FAO/OMS expert consultation and whether it is possible to propose preventive and/or adjuvant therapeutic recommendations. Prospective and case-control observational studies published since 2007 and meeting validity criteria were considered together with RCT. Experimental studies are mentioned to provide for biological plausibility. When evaluating the level of evidence, a portfolio approach was used, weighted by a hierarchy giving higher importance to prospective studies followed by RCT if any. There is a probable level of evidence that ALA per se is neither a risk factor nor a beneficial factor with regards to cancers. Observational studies on colorectal, prostate and breast cancers only provided limited evidence suggesting a possible role of LC-ω3PUFA in cancer prevention because insufficient homogeneity of the observations. Explanation for heterogeneity might be the inherent difficulties associated with epidemiology (confounding and dietary pattern context, measurement error, level of intake, genetic polymorphism). The role of LC-ω3PUFA as adjuvant, might be considered of possible use, in view of the latest RCT on lung cancers even if RCT on other cancers still need to be undertaken.

The Mediterranean diet: effects on proteins that mediate fatty acid metabolism in the colon

A Mediterranean diet appears to have health benefits in many domains of human health, mediated perhaps by its anti-inflammatory effects. Metabolism of fatty acids and subsequent eicosanoid production is a key mechanism by which a Mediterranean diet can exert anti-inflammatory effects. Both dietary fatty acids and fatty acid metabolism determine fatty acid availability for cyclooxygenase- and lipoxygenase-dependent production of eicosanoids, namely prostaglandins and leukotrienes. In dietary intervention studies and in observational studies of the Mediterranean diet, blood levels of fatty acids do reflect dietary intakes but are attenuated. Small differences in fatty acid levels, however, appear to be important, especially when exposures occur over long periods of time. This review summarizes how fat intakes from a Greek-style Mediterranean diet can be expected to affect fatty acid metabolizing proteins, with an emphasis on the metabolic pathways that lead to the formation of proinflammatory eicosanoids. The proteins involved in these pathways are ripe for investigation using proteomic approaches and may be targets for colon cancer prevention.

Overall diet quality and age-related macular degeneration

PURPOSE

To examine overall diet quality in relation to advanced age-related macular degeneration (AMD).

METHODS

This case-control study identified 437 advanced AMD patients and 259 unrelated controls using stereoscopic color fundus photographs. Participants were predominantly non-Hispanic White men and women from North Carolina and Tennessee. A 97-item Block food frequency questionnaire was used to gather diet information, and overall diet quality was measured using the Healthy Eating Index (HEI) and Alternate Healthy Eating Index (AHEI).

RESULTS

Participants in the highest quartile of diet quality had significantly reduced odds of AMD according to the AHEI score (0.54, 95% confidence interval 0.30-0.99) and non-significantly reduced odds of AMD according to the HEI (0.75, 0.41-1.38). Odds of AMD were also 51% lower in the highest quartile of fish intake compared to the lowest quartile (odds ratio = 0.49, 0.26-0.90).

CONCLUSIONS

We found that advanced AMD was significantly related to overall diet quality. The AHEI score may be a useful instrument for assessing AMD risk due to diet, and it could potentially be improved by incorporating more specific information regarding micronutrient intake.

Evaluation of diet quality with the mediterranean dietary quality index in university students

Data on diet quality in Croatian university students have been missing for more than 15?years. A food approach rather than a nutrient approach appears more appropriate to present knowledge on diet and health. The aim of the present study was to evaluate diet quality in Croatian university students (n = 663) with the Mediterranean Dietary Quality Index (M-DQI) in continental and Mediterranean regions. The M-DQI was determined with a Quantified Food Frequency Questionnaire. The minimum score for the M-DQI is 0 and the maximum score is 14. A higher score indicates a less healthy diet. The score for the M-DQI was the same in both regions (9.6) and did not differ significantly. In the category for scores 8-14 were 84.0% and 84.6% of students in the continental and Mediterranean regions, respectively. Higher correlation for the M-DQI was observed with macronutrient intakes than with micronutrient intakes. The M-DQI did not correlate with trans-fatty acid intake. A significant correlation (negative) with lycopene was observed in the Mediterranean region only. The body mass index did not correlate with the M-DQI. Students from both regions, continental and Mediterranean, had a lower diet quality evaluated with the M-DQI, with no significant difference according to region.

Validity of dietary patterns to assess nutrient intake adequacy

The purpose of the present study was to conduct a systematic review of the literature on the value of the methods used to assess dietary patterns for measuring nutrient intake adequacy in the population. Systematic review on Pubmed database up to April 2008. The search included specific key words and MeSH terms. No language limit was set. Only studies that compared food patterns with nutrient intake adequacy or nutrient biomarkers were included in the analysis. The search resulted in 1504 articles. The inclusion and exclusion criteria limited the selection to thirty articles. Nineteen studies evaluated the usefulness of the dietary patterns, eithera prioridefined (thirteen studies), or defined by factor analysis (four studies) or by cluster analysis (two studies), but only nine of them tested their validity (foura prioridefined and foura posterioridefined). Diet indices showed moderate to good validity results for measuring the adequacy of intakes for α-carotene, β-carotene, vitamin C, vitamin B6, Ca, folic acid, Fe and Mg. The factor analysis approach showed moderate to good validity correlations with the adequacy of intake of α-carotene, β-carotene, lutein, lycopene, vitamin C, vitamin B6and folic acid. Vitamin B12and vitamin E are the micronutrients with less probability of being adequately assessed with dietary patternsa prioriora posterioridefined. Diet indices are tools with fair to moderate validity to assess micronutrient intake adequacy.

Diet quality of a population sample from coastal north-east Spain evaluated by a Mediterranean adaptation of the diet quality index (DQI)

OBJECTIVE

To assess the adherence to the Mediterranean dietary pattern in the population from a coastal region from north-east Spain and its relationship to diseases, applying the Mediterranean Diet Quality Index (M-DQI) validated by the use of several biomarkers.

DESIGN

Cross-sectional nutrition survey.

SETTING

Population-based random sample derived from the Catalan Nutrition Survey.

SUBJECTS

A total of 621 healthy adults.

RESULTS

The Catalan representative sample presented a mean M-DQI score of 6.6 (sd 2.3, median 7, range 0-14). The percentage of adherence to the Mediterranean diet was 53 %; 10 % of subjects showed high adherence to the Mediterranean diet, while only 2 % were categorized as poorest adherence. The plasma fatty acid profile of the Catalan sample progressed with perfect regularity throughout the index ranges. Both EPA and DHA presented a significant correlation to the M-DQI (r = -0.410 for EPA and -0.360 for DHA). A significant increase in palmitic, oleic and alpha-linolenic acids and a significant decrease in stearic, linoleic and arachidonic acids content were also observed. The mean values for the M-DQI according to the clinical characteristics of the Catalan sample were also calculated.

CONCLUSIONS

The M-DQI has been demonstrated a suitable tool for assessment of an individual's nutritional status according to the Mediterranean dietary pattern and for clinical purposes. Although the current diet followed in Catalonia seems to agree with the main characteristics of the Mediterranean diet, the promotion of the Mediterranean pattern should be reinforced in the Catalan population, especially among young people.

A Mediterranean dietary intervention in healthy American women changes plasma carotenoids and fatty acids in distinct clusters

This study examined patterns of changes in plasma fatty acids and carotenoids when women were asked to follow a novel, Greek-Mediterranean exchange list diet. A total of 69 healthy, nonobese women ages 25 to 59 years were randomized either to continue their own usual diet or to follow a modified Mediterranean diet for 6 months. There were no significant changes in blood lipids, triacylglycerol, insulin, glucose, or C-reactive protein. Mean plasma carotenoids increased by 55%, which is consistent with a large increase in fruit and vegetable consumption. Likewise, changes in fat intakes were reflected in blood fatty acids, with a 25% increase in mean plasma monounsaturated fatty acids. Principal component analysis was conducted to examine the sources of interindividual variation for changes in carotenoid and fatty acid levels. Changes in the Mediterranean diet were clustered together in 4 components that accounted for 78% of the variance in plasma levels. Increases in plasma lutein, alpha-carotene, and beta-carotene clustered together in a "vegetable" pattern, and increases in carotenoids found in fruit, beta-cryptoxanthin and zeaxanthin also clustered together but accounted for less of the variance. Increases in plasma monounsaturated fatty acids were clustered with a decrease in plasma polyunsaturated fatty acids, consistent with substitution in the type of oils consumed. The only association of fatty acid levels with carotenoids was that of lycopene, which clustered together with an increase in saturated fatty acids. The changes in blood levels indicate the exchange list diet was effective for targeting Mediterranean nutrient intakes using foods available in the United States.

Diet quality – what is it and does it matter?

Objective

Measures of diet quality have evolved with a number of scoring indices currently in use. They are increasingly being used to examine epidemiological associations between dietary intake and nutrition-related health outcomes. The present review aims to describe current diet quality tools and their applications, and to examine the relationship between diet quality and morbidity and mortality.

Design

A search was conducted of MEDLINE, Cochrane, EMBASE, CINAHL and ProQuest electronic databases. Inclusion criteria were: English language; published from 2004 on; conducted in adult populations; longitudinal/cohort/case–control or cross-sectional study; included a theoretically defined measure of diet quality.

Results

A total of twenty-five indices of overall diet quality and/or variety were found, with components ranging from nutrients only to adherence to recommended food group servings, to variety within healthful food groups. The majority of studies reviewed had methodological weaknesses but demonstrated that higher dietary quality was consistently inversely related to all-cause mortality, with a protective effect of moderate magnitude. The associations were stronger for men and for all-cause and CVD mortality.

Conclusions

The limitations of both the indices and the studies that use them need to be considered when interpreting and comparing results. However, diet quality indices do appear to be able to quantify risk of some health outcomes, including biomarkers of disease and risk of CVD, some cancers and mortality. Further research is needed to improve the validity of these tools and to adapt them for use in clinical dietetic practice.

Dietary quality is associated with diabetes and cardio-metabolic risk factors

In this study, our aim was to investigate the associations between diet quality and newly diagnosed diabetes, prediabetes, and cardio-metabolic risk factors. The analysis was based on 7441 participants of the Australian Diabetes, Obesity and Lifestyle study, a cross-sectional study of adults aged > or =25 y involving a 75-g oral glucose tolerance test. Diet quality was assessed via a dietary guideline index and FFQ data. Associations between diet quality and diabetes, prediabetes (impaired fasting glycemia, impaired glucose tolerance), and cardiovascular risk factors were investigated using linear and logistic regression adjusted for age, education, smoking, physical activity, sedentary behavior, and BMI. Higher diet quality was significantly associated with lower systolic and diastolic blood pressure among men, lower fasting plasma glucose among men and women, and lower systolic blood pressure, fasting plasma insulin, and 2-h plasma glucose and greater insulin sensitivity among women. Diet quality was inversely associated with abdominal obesity [odds ratio (OR) for top quartile: 0.68, 0.48-0.96], hypertension (OR: 0.50, 0.31-0.81), and type 2 diabetes (OR: 0.38, 0.18-0.80) among men. Lack of compliance with established dietary guidelines was associated with type 2 diabetes and cardio-metabolic risk factors. Further work is required to determine whether this dietary index has predictive validity for health in longitudinal studies.

Design of a Mediterranean exchange list diet implemented by telephone counseling

A Greek-Mediterranean dietary pattern has two distinct aspects that differ relative to average intakes in the United States: a high intake of monounsaturated fats and a high intake of fruit and vegetables. The purpose of the study was to develop and test an exchange list Greek-Mediterranean diet that could be used in future clinical trials of breast cancer prevention. A total of 69 women, ages 25 to 59 years, were randomized to either continue their own usual diet or follow an intervention diet for 6 months during 2004 through 2005. Intervention goals were to decrease usual fat intakes by about half and to replace those fats with olive oil and other high-monounsaturated fatty acid foods; increase fruit and vegetable intakes to 7 to 9 servings/day, depending on energy intake; and consume at least one serving per day each of culinary herbs and allium vegetables. Registered dietitians provided exchange goals and individualized telephone counseling, and diets were self-selected using a Mediterranean exchange list developed specifically for this study. Changes in diet were assessed by 7-day food records. Results demonstrated that counseling using the Mediterranean exchange list was effective for large dietary changes relative to the nonintervention group. Repeated measures analysis of variance indicated a statistically significant 48% increase in dietary monounsaturated fat with no appreciable change in total fat intake, and a significant increase in fruit and vegetable intake from 4.0 to 8.6 servings/day (P < 0.05).

Dietary quality indices and human health: a review

Indices are composite tools aiming to measure and quantify a variety of clinical conditions, behaviors, attitudes and beliefs that are difficult to be measured quantitatively and accurately. In this review, the methodology used to develop dietary indices and their relationship with health determinants and outcomes is discussed. In brief, the already proposed indices are adequate tools concerning the evaluation of diet quality, but they have shown moderate predictive ability in relation to chronic diseases and health determinants. The aforementioned weaknesses could be attributed to: inappropriate selection of the components (i.e., number or content of dietary information), selection of small number of cut-off points for each component and/or equal contribution of all index items to the calculation of the total score. Nevertheless, dietary indices are important tools to evaluate not only the diet quality, but also the relationship between dietary habits and several health outcomes.

Indices of diet quality

PURPOSE OF REVIEW

The present review provides an overview of the different dietary quality indices in use. In the first decades, most indices were developed for the general adult population and were based on the American dietary guidelines and the Mediterranean diet. This review focuses on new, other dietary quality indices with special attention to the make-up of the score and methodological issues.

RECENT FINDINGS

Most of the new diet quality indices are based on the national dietary recommendations in Europe and Australia. In addition, one index is based on international recommendations and two indices use recommendations for the prevention of specific diseases. In addition, there are dietary scores that focus on specific groups (children, pregnant women), and on dietary variety or diversity.

SUMMARY

The use of diet quality indices becomes more widespread and tailored to the specific purpose and population. However, different approaches are also due to arbitrary choices because of lacking knowledge on healthy diets and unsolved methodological issues. The ways of dealing with differences in energy intake, scoring each component, and combining the different components into one measure are aspects that still need further research.

Patterns of alcohol (especially wine) consumption and breast cancer risk: a case-control study among a population in Southern France

PURPOSE

The association between alcohol consumption and breast cancer has been largely investigated, but few studies have investigated the effects of average intake when the pattern of drinking is taken into account. We sought to examine the association between drinking pattern of alcoholic beverages, particularly wine, and breast cancer using different statistical approaches.

METHODS

Our study included 437 cases of breast cancer, newly diagnosed in the period 2002-2004, and 922 residence- and age-matched controls.

RESULTS

Women who had an average consumption of less than 1.5 drinks per day had a lower risk (odds ratio [OR] = 0.58, 95% confidence interval [CI] = 0.34-0.97) when compared with nondrinkers. This protective effect was due substantially to wine consumption since the proportion of regular wine drinkers is predominant in our study population. Furthermore, women who consumed between 10 and 12 g/d of wine had a lower risk (OR = 0.51; 95% CI = 0.30-0.91) when compared with non-wine drinkers. Above 12 g per day of wine consumption, the risk of breast cancer increased, but the association was nonsignificant.

CONCLUSIONS

Although no association between the pattern of total alcohol consumption and breast cancer was found, the type of alcoholic beverage seemed to play an important role in this association. Our results support the hypothesis that there is a threshold effect that risk decreased or was not modified for consumption under a certain threshold. Above that threshold, risk increased, however. The drinking pattern of each type of specific beverage, especially wine, seems important in terms of alcohol-breast cancer association. Low and regular wine consumption does not increase breast cancer risk.

High consumptions of grain, fish, dairy products and combinations of these are associated with a low prevalence of metabolic syndrome

OBJECTIVE

To analyse the relation between various food groups and the frequency of insulin resistance syndrome (IRS).

DESIGN

A sample of 912 men aged 45-64 years was randomly selected. Questionnaires on risk factors and a three consecutive day food diary were completed. Height, weight, waist circumference, and blood pressure were measured. A fasting blood sample was analysed for lipid and glucose measurements. The NCEP-ATP-III definition was used to assess IRS. Data were analysed according to quintiles of food groups and medians of dairy products, fish, or cereal grains.

RESULTS

The prevalence of IRS was 23.5%. It reached 29.0%, 28.1% and 28.1% when the intake was below the median for fish, dairy products, and grain, respectively. When consumptions of all three types of food were higher than the median, the prevalence reached 13.1%, and when they were lower, the prevalence was 37.9% (p<0.001). In logistic regression adjusted for confounders (centre, age, physical activities, education level, smoking, dieting, alcohol intake, treatments for hypertension and dyslipidaemia, energy intake, and diet quality index) the odds ratios for IRS (above median value v below) were 0.51 (95% confidence interval, 0.36 to 0.71) for fish, 0.67 (0.47 to 0.94) for dairy products, and 0.69 (0.47 to 1.01) for grain. When intakes of all three kinds of food were high, the OR was 0.22 (0.10 to 0.44).

CONCLUSIONS

A high consumption of dairy products, fish, or cereal grains is associated with a lower probability of IRS. The probability decreases when intakes of all three types of food were high.

The Diet Quality Index-Revised: A Tool to Promote and Evaluate Dietary Change among Older Cancer Survivors Enrolled in a Home-Based Intervention Trial

OBJECTIVE

To utilize the Diet Quality Index-Revised (DQI-R) as a framework for delivering and evaluating an intervention to improve overall diet quality among older cancer survivors.

DESIGN

As part of a randomized controlled trial to improve lifestyle behaviors among older cancer survivors, we sought a dietary measure that could serve as both an intervention framework and a means to evaluate global dietary quality. The DQI-R measures overall diet quality by summing 10 subscales that relate to national guidelines. At baseline, DQI-R scores were generated from three multi-pass 24-hour dietary recalls. The 6-month intervention delivered tailored feedback on individual DQI-R subscales. Dietary recalls were repeated at 6 and 12 months.

SUBJECTS

Elderly (aged >or=65 years) individuals within 18 months of diagnosis of breast or prostate cancer (n=182) were randomized postbaseline measures to intervention vs attention control arms.

RESULTS

Significant differences in overall diet quality were observed between arms at 6 months, with the intervention arm improving (67.6+/-12.2 to 69.8+/-13.9), and controls declining (67.5+/-12.5 to 64.6+/-14.7) (P=0.003). Significant differences were observed between arms over time in dietary diversity subscale scores: baseline and 6-month follow-up means among intervention and control arms were 4.8+/-1.3 to 4.8+/-1.4, and 4.7+/-1.2 to 4.1+/-1.1, respectively (P=0.001).

CONCLUSIONS

The DQI-R served as an effective guide and evaluation tool for this diet-related randomized controlled trial. Like many interventions, our effect diminished after the intervention was complete. Future research should consider testing interventions that use the DQI-R, or other global diet-related indexes, as guides and evaluation tools over longer study periods, as well as in other populations.

Diet quality of young people in southern Spain evaluated by a Mediterranean adaptation of the Diet Quality Index-International (DQI-I)

The aim of this study was to assess whether the recently developed Diet Quality Index-International (DQI-I) was useful to evaluate the diet quality of a young Mediterranean population. A cross-sectional nutritional survey was carried out in southern Spain (Granada-Andalucia) from 2002 to 2005. Dietary information (24 h recall and FFQ) and socio-demographic and lifestyle data were collected from a representative sample of the population (n 288, 44.1 % females and 55.9 % males) aged 6-18 years (mean 12.88 (sd 2.78) years). DQI-I was designed according to the method of Kim et al. modified by Tur et al. for Mediterranean populations. It focused on four main characteristics of a high-quality diet (variety, adequacy, moderation and overall balance). This young population from southern Spain obtained 56.31 % of the total DQI-I score, indicating a poor-quality diet. A higher score was associated with a longer breakfast and greater physical activity. The DQI-I may require further modification for application in Mediterranean populations, differentiating between olive oil and saturated fats, among other changes. Further research is needed to develop a new diet quality index adapted to the Mediterranean diet.

A critical review of predefined diet quality scores

The literature on predefined indexes of overall diet quality is reviewed. Their association with nutrient adequacy and health outcome is considered, but our primary interest is in the make-up of the scores. In total, twenty different indexes have been reviewed, four of which have gained most attention, and many others were based on those four. The various scores differ in many respects, such as the items included, the cut-off values used, and the exact method of scoring, indicating that many arbitrary choices have been made. Correlations in intake between dietary components may not be adequately addressed. In general, diet quality scores show an association with mortality or disease risk, but these relations are generally modest. Existing indexes do not predict morbidity or mortality significantly better than individual dietary factors. Although conclusions from the review may provide guidance in the construction of a diet quality score, it is questionable whether a dietary score can be obtained that is a much better predictor of health outcome.

Qualitative methods to evaluate Mediterranean diet in adults

Objective

To fulfil a comprehensive approach to consumption, which is necessary to characterise food habits and their relationship to diseases, using a diet quality index (DQI) developed for a Mediterranean region (Med-DQI).

Setting

A cross-sectional nutritional survey provided the data for the construction of the DQI.

Subjects

A representative sample made up of 964 subjects from a French Mediterranean area, Hérault département.

Methods

Foods such as olive oil, fish and cereals were used instead of nutrients to build up scores which constructed the Med-DQI. Biochemical analysis identified biomarkers used to validate the Med-DQI. Correspondence factorial analysis illustrated the characteristics of subjects with different scores given by the Med-DQI.

Results

The subjects could be satisfactorily classified by the Med-DQI. The oldest age, less educated, overweight, manual workers, living in a rural area and male classes showed a better Med-DQI. For women, they were also from the oldest age class, but some of them were from the upper social class, with an ideal BMI and lived by the Mediterranean shore. A composite biomarker index, based on plasma carotene and vitamin E levels and the percentage of EPA and DHA in erythrocytes membranes, can identify subjects with good and poor Med-DQI.

Conclusion

Med-DQI G is a good instrument to identify groups at risk with regard to nutritional quality. Subjects with α+β-carotene levels > 1 mg/l, vitamin E > 30 mg/l, EPA > 0.65% and DHA > 4% of fatty acids in erythrocytes are likely to have a good diet.

Selected nutritional biomarkers predict diet quality

Objective:

To examine associations of biomarkers of nutrient intake with overall diet quality.

Subjects:

A convenience sample of 102 healthy postmenopausal women in Seattle, Washington (USA).

Design and method:

Participants attended a study centre where they provided fasting blood specimens and completed a 122-item validated food-frequency questionnaire (FFQ). Data from the FFQ were used to calculate Diet Quality Index (DQI) scores and categorise women as having diets of excellent, good, fair or poor quality. The blood specimens were analysed for nine phospholipid fatty acids (as percentage of total) and serum concentrations of vitamin C, α-tocopherol, γ-tocopherol, vitamin B12, folate and six carotenoids. Multivariate linear regression was used to model associations of the nutrient biomarkers with DQI scores.

Results:

Compared with women with poor-quality diets, women with excellent diets, as measured by the DQI, had higher plasma concentrations of vitamin C (Pfor trend = 0.01), α-tocopherol (Pfor trend = 0.02) and β-cryptoxanthin (Pfor trend = 0.03). Women with excellent diets also had lower proportions of plasma phospholipid fatty acids of two potentially atherogenic fatty acids: stearic acid (Pfor trend = 0.01) and behenic acid (Pfor trend = 0.03). A group of six biomarkers explained a moderate proportion of the total variability in DQI scores (36%).

Conclusions:

These objective measures of dietary intake support the use of the DQI as a useful tool to measure dietary patterns.

Evaluating associations between Mediterranean diet adherence indexes and biomarkers of diet and disease

Objective

We examined associations between two Mediterranean diet (MD) adherence indexes (the MD index, MDI, and the MD score, MDS) and several blood biomarkers of diet and disease.

Subjects

We studied 328 individuals from Catalonia (Northeastern Spain), ages 18–75, who provided fasting blood samples, a subset of the 2346 individuals as part of a larger representative and random sample from the 1992–1993 Catalan Nutritional Survey.

Design and method

Diet was measured using 24-h recalls. Biomarkers studied were plasma levels of β-carotene, α-tocopherol, retinol, vitamins B12, C and folates as well as serum total cholesterol, HDL cholesterol, LDL cholesterol and triglycerides. Multivariate linear regression was used to analyse associations of the nutrient biomarkers with the dietary pattern indexes, adjusting for potential confounders.

Results and conclusions

Subjects with higher MD adherence, as measured by the two dietary indexes, had significantly higher plasma concentrations of β-carotene, folates, vitamin C, α-tocopherol and HDL cholesterol. The most highly significant relationship was that between folates and the adherence to the MD Pattern, as determined by both indexes.

These research findings suggest the potential usefulness of biomarkers as complementary tools for assessing adherence to a dietary pattern. This type of data not only informs the development of robust dietary adherence indexes, but it also provides specific clues about the potential physiological mechanisms that explain the beneficial effects of the MD pattern on chronic disease risk.

Independent contribution of dairy products and calcium intake to blood pressure variations at a population level

PURPOSE

Previous studies have shown a potential inverse relationship between blood pressure and daily calcium intake. The aim of the study was to assess the independent contribution of dairy product and calcium intake to blood pressure variations at a population level.

METHODS

A sample of 912 men aged 45-64 years was randomly selected from the general population, as part of the French MONICA cross-sectional survey on cardiovascular risk factors (1995-1996). Extensive questionnaires on risk factors were filled out and each participant completed a three-consecutive-day food record. Two blood pressure measurements were performed at rest. In statistical analyses subjects were grouped according to quintiles of dairy product or calcium intakes.

RESULTS

Systolic and diastolic blood pressures significantly decreased from the lowest [145.4 (standard error (SE) 1.55) and 89.0 (SE 0.94) mmHg respectively] to the highest quintile [135.6 (SE 1.26) and 85.3 (SE 0.84) mmHg respectively] of dairy product intakes in bivariate analysis. After multivariate linear regression analysis adjusted for confounders [centre, age, daily sodium, magnesium, calcium and alcohol intake, daily energy intake without alcohol, dieting, physical activity, body mass index (BMI), smoking, and use of antihypertensive or lipid-lowering drugs], the difference in systolic blood pressure remained significant. Results were similar when calcium intake was considered. After adjustment for confounders, the association between calcium-dairy product combination and blood pressure was the most significant when intakes of dairy products and calcium were both higher than the median.

CONCLUSION

Dairy products and dietary calcium are both significantly and independently associated with low levels of systolic blood pressure.

The Medi-RIVAGE study: reduction of cardiovascular disease risk factors after a 3-mo intervention with a Mediterranean-type diet or a low-fat diet

BACKGROUND

Epidemiologic studies link Mediterranean-type diets to a low incidence of cardiovascular disease; however, few dietary intervention studies have been undertaken, especially in primary prevention.

OBJECTIVES

In the Mediterranean Diet, Cardiovascular Risks and Gene Polymorphisms (Medi-RIVAGE) study, the effects of a Mediterranean-type diet (Med group) or a low-fat diet (low-fat group) on risk factors were evaluated in 212 volunteers (men and women) with moderate risk factors for cardiovascular disease.

DESIGN

After the 3-mo dietary intervention, changes in many risk factors were evaluated. Dietary questionnaires and plasma nutritional markers were used to test compliance.

RESULTS

Although the dietary goals were only partially reached, changes in dietary habits were observed in both groups (n = 169): protein, carbohydrate, and fiber intakes increased and fat quality (decreased saturated fat and increased monounsaturated or polyunsaturated fat) improved. BMI, total and triacylglycerol-rich lipoprotein (TRL) cholesterol, triacylglycerols, TRL triacylglycerols, apolipoproteins A-I and B, insulinemia, glycemia, and the homeostasis model assessment score were significantly lower after 3 mo. The reductions in total cholesterol, triacylglycerols, and insulinemia remained significant after adjustment for BMI. There was a trend for a diet-by-time interaction for LDL cholesterol (P = 0.09). Our data predicted a 9% reduction in cardiovascular disease risk with the low-fat diet and a 15% reduction with this particular Mediterranean diet.

CONCLUSION

After a 3-mo intervention, both diets significantly reduced cardiovascular disease risk factors to an overall comparable extent.

A Comparison of Three Dietary Pattern Indexes for Predicting Biomarkers of Diet and Disease

OBJECTIVE

Examination of dietary indexes in association with objective biomarkers of dietary intake and chronic disease risk is an important step in their validation. We compared three dietary pattern indexes-Healthy Eating Index (HEI), Recommended Foods Score (RFS-24 hour recall), and Dietary Diversity Score for recommended foods (DDS-R)-for their ability to predict biomarkers of dietary intake, obesity, cardiovascular disease, and diabetes.

METHODS

We used dietary and laboratory data from the third National Health and Nutrition Examination Survey to study these associations in 8719 disease-free adults aged > or =20 y. The HEI, developed by the USDA, was a sum of scores on consideration of ten individual components; the RFS was a sum of all recommended foods (lean meat, poultry and fish, whole grains, fruits and juices, low-fat dairy, and vegetables) mentioned in the recall; the DDS-R examined whether or not a recommended food was mentioned from each of the five major food groups. The independent association of the dietary pattern indexes with body mass index (BMI), blood pressure, and serum concentrations of several biomarkers were examined using regression methods to adjust for multiple covariates.

RESULTS

All indexes were strong independent positive predictors of serum concentrations of vitamin C, E, folate, and all carotenoids (p < or = 0.00001), except lycopene, and were negative predictors of BMI, serum homocysteine, C-reactive protein, plasma glucose, and hemoglobin A1C (p < 0.05). The RFS and DDS-R were inversely associated with blood pressure and serum cholesterol (p < or = 0.03).

CONCLUSIONS

The RFS and DDS-R performed as well or better than the HEI for predicting serum concentration of nutrients and biomarkers of disease risk.