The relationship between dietary patterns and lipoprotein-associated phospholipase A2 levels in adults with cardiovascular risk factors: Tehran Lipid and Glucose Study

Associations between healthy food groups and platelet-activating factor, lipoprotein-associated phospholipase A2 and C-reactive protein: a cross-sectional study

PURPOSE

To investigate the association between pro-inflammatory markers platelet-activating factor (PAF), lipoprotein-associated phospholipase A2 (Lp-PLA2), hsCRP, and intake of core food groups including fruit, cruciferous and other vegetables, grains, meat and poultry, fish and seafood, nuts and legumes, and dairy.

METHODS

A cross-sectional study was conducted. 100 adults (49 ± 13 years, 31% male) with variable cardiovascular disease risk were recruited. Data were collected in 2021 and 2022. Fasting PAF, Lp-PLA2 activity, hsCRP and usual dietary intake (via a validated food frequency questionnaire) were measured. Intake of foods were converted into serves and classified into food groups. Correlations and multiple regressions were performed with adjustment for confounders.

RESULTS

A one-serve increase in cruciferous vegetables per day was associated with 20-24% lower PAF levels. An increase of one serve per day of nuts and legumes was associated with 40% lower hsCRP levels. There were small correlations with PAF and Lp-PLA2 and cheese, however, these were not significant at the Bonferroni-adjusted P < 0.005 level.

CONCLUSION

The lack of associations between PAF and Lp-PLA2 and other healthy foods may be due to confounding by COVID-19 infection and vaccination programs which prevents any firm conclusion on the relationship between PAF, Lp-PLA2 and food groups. Future research should aim to examine the relationship with these novel markers and healthy food groups in a non-pandemic setting.

Maternal Adherence to a Dietary Approaches to Stop Hypertension (DASH) Dietary Pattern and the Relationship to Breast Milk Nutrient Content

BACKGROUND

Maternal lifestyle factors, such as diet and nutritional status are likely to affect the composition of breast milk (BM). This study aimed to investigate the association between adherence to a Dietary Approaches to Stop Hypertension (DASH) dietary pattern (DP) and BM nutrient content.

METHOD

A total of 700 milk samples were obtained from 350 lactating women. The dietary intakes of the women in the study were estimated using a validated food frequency questionnaire, which included 65 food items. The total antioxidant activity (TAC) of BM samples was evaluated using the Ferric reducing antioxidant power (FRAP), 2,2'-diphenyl-1-picrylhydrazyl (DPPH), thiobarbituric acid reactive substances (TBARS), and Ellman's assay. Also using commercially available kits, the total protein, calcium, and triglyceride contents in milk were determined.

RESULTS

Individuals in the 3rd tertile of adherence to the DASH diet (highest adherence) consumed more dietary fiber, fruits, vegetables, nuts, legumes, and seeds, low-fat dairy, whole grain, less red and processed meat, sweetened beverages, and sodium than those in the first tertile (lowest adherence). Subjects in the 3rd tertile of DASH DP had higher values of milk DPPH and calcium compared to those in the first tertile (P < 0.05). Milk MDA and triglyceride were significantly lower in the 3rd tertile of DASH diet versus the first tertile (P < 0.05).

CONCLUSION

Our study showed that high adherence to the DASH DP was associated with higher BM DPPH and calcium levels and lower amounts of BM MDA and triglyceride. The adherence to the healthy DPs such as the DASH can improve the quality of BM in lactating women.

The association between dietary patterns and the novel inflammatory markers platelet-activating factor and lipoprotein-associated phospholipase A2: a systematic review

CONTEXT

Atherosclerosis is a disease of chronic inflammation. Recent research has identified 2 novel inflammatory biomarkers: platelet-activating factor (PAF) and lipoprotein-associated phospholipase A2 (Lp-PLA2). Diet has been proposed as a mediator of inflammation, but to date, the focus for these novel biomarkers has been on individual foods and nutrients rather than overall dietary patterns.

OBJECTIVE

To systematically review the literature on the association between dietary patterns and PAF and Lp-PLA2.

DATA SOURCES

The PubMed, Embase, CINAHL, and Cochrane CENTRAL literature databases were searched.

DATA ANALYSIS

Study quality was evaluated using the Quality Criteria Checklist. Sixteen studies (n = 4 observational and n = 12 interventional) were included and assessed for associations between dietary patterns and PAF and Lp-PLA2.

CONCLUSION

Study quality varied from neutral (n = 10) to positive (n = 6). Mediterranean, heart healthy, and vegetarian dietary patterns were associated with improved levels of PAF and Lp-PLA2. Conversely, Western dietary patterns were less favorable. A range of well-established, healthier dietary patterns may lower inflammation and the risk of atherosclerosis. More well-designed studies are needed to confirm these findings and identify other dietary patterns that improve inflammation.

Dietary patterns and biomarkers of oxidative stress and inflammation: A systematic review of observational and intervention studies

INTRODUCTION

Oxidative stress and inflammation are known to play a critical role in ageing and chronic disease development and could therefore represent important targets for developing dietary strategies for disease prevention. We aimed to systematically review the results from observational studies and intervention trials published in the last 5 years on the associations between dietary patterns and biomarkers of oxidative stress and inflammation.

METHODS

A systematic search of the PubMed, MEDLINE and Web of Science (January 2015 to October 2020) was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Methodological quality of selected studies was evaluated based on the NUTRIGRADE and BIOCROSS assessment tools.

RESULTS

In total, 29 studies among which 16 observational studies and 13 intervention studies were found eligible for review. Overall, results indicated an inverse association between plant-based diets - the Mediterranean and Dietary Approaches to Stop Hypertension (DASH) diet - and oxidative stress and proinflammatory biomarkers. In observational studies, inverse associations were further revealed for the vegetarian diet, the USDA Healthy Eating Index (HEI) - based diet and the paleolithic diet, whereas a positive association was seen for western and fast food diets. Quality assessment suggested that majority of dietary intervention studies (n = 12) were of low to moderate quality.

CONCLUSIONS

This study provides evidence that the plant-based dietary patterns are associated with lowered levels of oxidative stress and inflammation and may provide valid means for chronic disease prevention. Future large-scale intervention trials using validated biomarkers are warranted to confirm these findings.

Interaction between major dietary patterns and cardiorespiratory fitness on metabolic syndrome in Iranian adults: a cross-sectional study

Background

Several researches have been conducted on the associations between diet and cardiorespiratory fitness (CRF) and major cardiovascular risk factors. However, there is no report about the interaction between major dietary patterns and CRF on metabolic syndrome (MetS) and its components. To investigate the combined association of major dietary patterns and CRF on MetS and its components.

Methods

This cross-sectional study was conducted on 270 apparently healthy adults living in Tehran, Iran. Dietary intake was evaluated using a validated food frequency questionnaire (FFQ). CRF was assessed using a graded exercise treadmill test. Socio-economic status, anthropometric measures, biochemical parameters, and blood pressure were evaluated according to standard methods. Major dietary patterns were identified by factor analysis.

Results

Three major identified dietary patterns were (healthy, mixed, and western). Significant positive association was found between mixed dietary pattern and metabolic syndrome (OR = 2.68, 95% CI (1.92,7.78), P = 0.04). There were not relations between tertiles of identified dietary patterns and remained outcomes. Those who had higher adherence to mixed pattern with also higher CRF showed a significant decrease for diastolic blood pressure (P < 0.01). Also we found that there was no significant interaction between any of dietary patterns and CRF on odds of MetS.

Conclusions

Overall, adherence to mixed dietary pattern in this population was associated with increasing odds of MetS. However, nor CRF neither the combination of dietary patterns and CRF was related to the odds of MetS among Iranian adults. More studies are needed to clarify these associations and to consider interpersonal determinants.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12937-021-00695-4.